feat(dllm): default gallery entry on Q4_K_M; add Q8_0 variant

Q4_K_M (~17 GB, GB10-validated: cosine 0.9862, coherent generation) is
the friendlier default download than the 50 GB BF16; Q8_0 (~27 GB) is
the higher-fidelity middle ground. Both descriptions carry the measured
caveat that BF16 is ~5x faster per denoise step on BF16-native hardware,
with a pointer to fetch it manually when it fits. sha256 values are the
HF LFS oids.

Assisted-by: Claude Code (Fable 5)
Signed-off-by: Ettore Di Giacinto <mudler@localai.io>

.agents/dllm-backend.md

@@ -0,0 +1,138 @@
+# Working on the dllm Backend
+
+`mudler/dllm.cpp` is a standalone C++/ggml engine for DiffusionGemma
+block-diffusion models. LocalAI wraps it with a **pure-Go** backend at
+`backend/go/dllm/` that dlopens `libdllm.so` via purego (ebitengine/purego) -
+NOT cgo, and NOT a C++ grpc-server fork. The Go side owns chat templating
+(gemma4 renderer) and output parsing (gemma4 streaming parser) and implements
+the rich gRPC interface (`PredictRich`/`PredictStreamRich`, ChatDelta replies).
+
+> NOTE: github.com/mudler/dllm.cpp is still **private** (publishing is
+> planned). Until then the Makefile's anonymous clone fails; use the local-dev
+> symlink shortcut documented at the top of `backend/go/dllm/Makefile`
+> (symlink an out-of-tree `build/libdllm.so` into the backend dir and skip the
+> clone), or a git credential helper with repo access.
+
+## Pin
+
+`backend/go/dllm/Makefile` pins `DLLM_VERSION?=<sha>` at the top
+(whisper / parakeet-cpp / ds4 convention). The bump-deps bot
+(`.github/workflows/bump_deps.yaml`) tracks `mudler/dllm.cpp` `main` and
+rewrites that variable. After a manual bump: `make -C backend/go/dllm purge &&
+make -C backend/go/dllm` (the clone is keyed on the directory existing, not
+the sha).
+
+## C-ABI and the serialization contract
+
+The binding covers the 9-symbol flat C-ABI from dllm.cpp's
+`include/dllm_capi.h` (ABI v1; `main.go` hard-fails on a version mismatch):
+`abi_version, load, free, last_error, free_string, tokenize_json, generate,
+generate_stream, cancel`. Contract points the Go wiring encodes (`capi.go`
+header comment has the full list):
+
+- **One ctx = one concurrent generate/tokenize.** A per-model worker
+  goroutine (`Dllm.jobs` in `dllm.go`) owns ALL C calls, making the
+  serialization structural instead of lock discipline.
+- **`dllm_capi_cancel` is the ONE exception**: it only flips an atomic and may
+  be called from any goroutine mid-generate, so `Dllm.Cancel` bypasses the
+  worker queue. The flag resets at the start of each generate, so a watchdog
+  racing a new generate must re-issue cancel.
+- **`last_error` is a borrowed pointer** and must only be read AFTER the
+  failing call returned (never while a generate is in flight on the same ctx).
+- **Free vs in-flight requests**: requests hold `genMu.RLock` for their full
+  duration; `Free` takes the write lock, so it only runs when nothing is in
+  flight, then drains and closes the worker. Post-Free requests get a clean
+  "model not loaded" error.
+- `tokenize_json`/`generate` return malloc'd `char*` (bound as `uintptr`,
+  copied, then `dllm_capi_free_string`d); opts/params JSON must be a FLAT
+  object of scalars (`buildOptsJSON` rejects anything else).
+
+## Wire shape
+
+| RPC | Implementation |
+|---|---|
+| LoadModel | `dllm_capi_load` (params: `n_gpu_layers`, `n_threads`, `ctx_len`); `Options[]` parsed into per-request gen opts (`eb_*`, `blocks`, `kv_cache`) by `parseModelGenOpts` |
+| PredictRich | render (if templated) → `dllm_capi_generate` → parse → ONE Reply with aggregated ChatDeltas + legacy `Message` bytes |
+| PredictStreamRich | `dllm_capi_generate_stream`; per committed diffusion block → UTF-8 holdback → parser.Feed → one Reply per non-empty delta batch (channel closed by the CALLER, per `pkg/grpc/interface.go`) |
+| Predict / PredictStream | Legacy paths, delegate to the rich pair (legacy stream INVERTS channel ownership: the impl closes) |
+| TokenizeString | `dllm_capi_tokenize_json` (C side prepends BOS per `vocab.add_bos`) |
+| Cancel | `dllm_capi_cancel`, exposed as the `grpc.Cancellable` capability (`pkg/grpc/interface.go`): the gRPC server arms it via `context.AfterFunc` on the Predict/PredictStream context, so client disconnects/timeouts abort the in-flight generate - llama.cpp `IsCancelled()` parity for Go backends |
+
+`n_threads` and `ctx_len` are accepted-but-ignored by the engine at the
+current pin (the context bound comes from GGUF `n_ctx_train`); they are sent
+for forward compatibility.
+
+## Renderer / parser (the templated chat path)
+
+With `use_tokenizer_template` + raw Messages, the backend owns templating and
+parsing (the ds4 precedent, but in Go):
+
+- `gemma4_renderer.go` - `RenderGemma4(msgs, toolsJSON, enableThinking,
+  addGenerationPrompt)`. The file embeds the FULL `tokenizer.chat_template`
+  jinja (17466 bytes, md5 `8c34cf93c7a7815b3fdb300a009c4c17`) extracted
+  verbatim from `diffusiongemma-26B-A4B-it-BF16.gguf` via gguf-py - e.g.
+  `python scripts/dump_gguf.py model.gguf | grep -A400 chat_template` in the
+  dllm.cpp checkout - as a numbered comment block; every Go rule cites its
+  "tpl L<n>" line. Re-verify the md5 before blaming the renderer for a
+  mismatch with a new GGUF. **BOS exception**: the template emits
+  `{{- bos_token -}}` but the renderer deliberately does NOT - dllm.cpp's
+  `run_generate` tokenizes with `prepend_bos = vocab.add_bos` (true for
+  gemma4), so a literal `<bos>` would double it.
+- `gemma4_parser.go` - streaming state machine turning raw model text
+  (fragments can split anywhere, including mid-marker) into ChatDeltas:
+  thought channels → `reasoning_content`, `<|tool_call>call:name{...}` →
+  ToolCallDelta, `<turn|>` → done. Marker grammar cross-checked against vLLM
+  PR #45163's gemma4 tool/reasoning parsers. Malformed payloads are re-emitted
+  raw as content, never dropped.
+- Thinking is **opt-in** for this family (`Metadata["enable_thinking"]`,
+  default OFF - the inverse of ds4): the template gates every thinking branch
+  on `enable_thinking`, and the no-thinking render pre-closes an empty thought
+  channel, so the parser always starts in content state.
+- **UTF-8 boundary holdback** (`splitValidUTF8` in `dllm.go`): per-block
+  detokenization can split a multi-byte character across block boundaries, and
+  grpc-go refuses to marshal invalid UTF-8 in proto3 strings. An incomplete
+  trailing sequence (at most 3 bytes) is carried into the next block; genuinely
+  undecodable bytes become U+FFFD.
+
+Without `use_tokenizer_template`, the prompt passes through verbatim and the
+output is NOT gemma4-parsed (plain content, like any non-autoparsing backend).
+
+## Tests
+
+| Layer | Gate | What |
+|---|---|---|
+| `backend/go/dllm/*_test.go` (renderer/parser/wiring) | none - run in plain `go test ./backend/go/dllm/...` | Ginkgo specs over a fake `generator` seam; canonical renderer fixtures from transformers' `test_modeling_diffusion_gemma.py`, parser tables from the vLLM gemma4 parsers |
+| `backend/go/dllm/dllm_test.go` C-ABI smoke | `DLLM_TEST_LIBRARY` + `DLLM_TEST_TINY_MODEL` (dllm.cpp's `tests/fixtures/tiny_with_vocab.gguf`); Skips when unset | Drives the real `libdllm.so`: ABI check, load, tokenize `[2,18]`, deterministic generate, cancel (incl. mid-stream `Dllm.Cancel` aborting a deliberately slow `eb_max_steps:256` run in ~10ms) |
+| `tests/e2e-backends/dllm_test.go` | `BACKEND_TEST_DLLM=1` + `BACKEND_BINARY` (packaged run.sh) + `BACKEND_TEST_MODEL_FILE` (tiny fixture) | Templated chat round trip (Messages + UseTokenizerTemplate) over the real gRPC binary, non-streaming + streaming; plus client-context cancellation mid-stream (proves the `Cancellable` server plumbing end to end) |
+| Real-model e2e | `BACKEND_TEST_DLLM_REAL_MODEL_FILE` (26B BF16, ~50 GB) + `BACKEND_TEST_DLLM_REAL_GPU_LAYERS` | CUDA-13-class hardware only |
+
+Tool-call e2e is deliberately absent from the tiny-model spec: the fixture has
+random weights and cannot be coaxed into emitting tool markup; the unit tables
+carry that coverage.
+
+## Build matrix
+
+`cpu-dllm` (amd64 + arm64), `cuda13-dllm` (amd64), and
+`cuda13-nvidia-l4t-arm64-dllm` (arm64 CUDA: Jetson / DGX Spark GB10), via
+`.github/backend-matrix.yml`. No darwin/Metal. CUDA builds forward
+`-DDLLM_CUDA=ON` (dllm.cpp gates ggml's CUDA behind its own flag - a bare
+`-DGGML_CUDA=ON` is overridden by the cache FORCE). `libdllm.so` is
+self-contained (ggml statically absorbed, PIC), so `package.sh` only ships
+the binary, `run.sh` and that one .so (the parakeet-cpp-style stub layout;
+no ldd walk yet).
+
+## Known limitations
+
+- **Cancel granularity**: the C-ABI cancel flag is per-ctx and resets on
+  every generate entry, so a Cancel racing a NEW generate can be lost, and
+  with requests queued on the worker it aborts whichever generate is
+  currently running (acceptable: the server de-registers the hook on normal
+  completion, one process serves one model).
+- **Throughput**: ~0.15 tok/s on the 26B at default settings (GB10) - every
+  denoise step recomputes the full prompt+canvas. The upstream prefix-KV
+  cache (dllm.cpp P3) is the fix; `kv_cache:on` errors until it lands
+  (`auto`/`off` are accepted no-ops).
+- **Repo privacy**: see the note at the top - CI clone of dllm.cpp needs the
+  repo published (or credentials) before the backend images can build.
+- Engine spec/validation references: dllm.cpp `docs/validation.md` and
+  LocalAI `docs/superpowers/specs/2026-06-10-dllm-cpp-design.md`.

.github/backend-matrix.yml

@@ -1608,6 +1608,19 @@ include:
     dockerfile: "./backend/Dockerfile.golang"
     context: "./"
     ubuntu-version: '2404'
+  - build-type: 'cublas'
+    cuda-major-version: "13"
+    cuda-minor-version: "0"
+    platforms: 'linux/amd64'
+    tag-latest: 'auto'
+    tag-suffix: '-gpu-nvidia-cuda-13-dllm'
+    runs-on: 'ubuntu-latest'
+    base-image: "ubuntu:24.04"
+    skip-drivers: 'false'
+    backend: "dllm"
+    dockerfile: "./backend/Dockerfile.golang"
+    context: "./"
+    ubuntu-version: '2404'
   - build-type: 'cublas'
     cuda-major-version: "13"
     cuda-minor-version: "0"
@@ -1647,6 +1660,19 @@ include:
     backend: "parakeet-cpp"
     dockerfile: "./backend/Dockerfile.golang"
     context: "./"
+  - build-type: 'cublas'
+    cuda-major-version: "13"
+    cuda-minor-version: "0"
+    platforms: 'linux/arm64'
+    skip-drivers: 'false'
+    tag-latest: 'auto'
+    tag-suffix: '-nvidia-l4t-cuda-13-arm64-dllm'
+    base-image: "ubuntu:24.04"
+    ubuntu-version: '2404'
+    runs-on: 'ubuntu-24.04-arm'
+    backend: "dllm"
+    dockerfile: "./backend/Dockerfile.golang"
+    context: "./"
   - build-type: 'cublas'
     cuda-major-version: "13"
     cuda-minor-version: "0"
@@ -3145,6 +3171,35 @@ include:
     dockerfile: "./backend/Dockerfile.golang"
     context: "./"
     ubuntu-version: '2404'
+  # dllm
+  - build-type: ''
+    cuda-major-version: ""
+    cuda-minor-version: ""
+    platforms: 'linux/amd64'
+    platform-tag: 'amd64'
+    tag-latest: 'auto'
+    tag-suffix: '-cpu-dllm'
+    runs-on: 'ubuntu-latest'
+    base-image: "ubuntu:24.04"
+    skip-drivers: 'false'
+    backend: "dllm"
+    dockerfile: "./backend/Dockerfile.golang"
+    context: "./"
+    ubuntu-version: '2404'
+  - build-type: ''
+    cuda-major-version: ""
+    cuda-minor-version: ""
+    platforms: 'linux/arm64'
+    platform-tag: 'arm64'
+    tag-latest: 'auto'
+    tag-suffix: '-cpu-dllm'
+    runs-on: 'ubuntu-24.04-arm'
+    base-image: "ubuntu:24.04"
+    skip-drivers: 'false'
+    backend: "dllm"
+    dockerfile: "./backend/Dockerfile.golang"
+    context: "./"
+    ubuntu-version: '2404'
   - build-type: 'sycl_f32'
     cuda-major-version: ""
     cuda-minor-version: ""

.github/workflows/bump_deps.yaml

@@ -38,6 +38,10 @@ jobs:
             variable: "PARAKEET_VERSION"
             branch: "master"
             file: "backend/go/parakeet-cpp/Makefile"
+          - repository: "mudler/dllm.cpp"
+            variable: "DLLM_VERSION"
+            branch: "main"
+            file: "backend/go/dllm/Makefile"
           - repository: "leejet/stable-diffusion.cpp"
             variable: "STABLEDIFFUSION_GGML_VERSION"
             branch: "master"

AGENTS.md

@@ -26,6 +26,7 @@ LocalAI follows the Linux kernel project's [guidelines for AI coding assistants]
 | [.agents/vllm-backend.md](.agents/vllm-backend.md) | Working on the vLLM / vLLM-omni backends — native parsers, ChatDelta, CPU build, libnuma packaging, backend hooks |
 | [.agents/sglang-backend.md](.agents/sglang-backend.md) | Working on the SGLang backend — `engine_args` validation against ServerArgs, speculative-decoding (EAGLE/EAGLE3/DFLASH/MTP) recipes, parser handling |
 | [.agents/ds4-backend.md](.agents/ds4-backend.md) | Working on the ds4 backend - DSML state machine, thinking modes, KV cache, Metal+CUDA matrix |
+| [.agents/dllm-backend.md](.agents/dllm-backend.md) | Working on the dllm backend (DiffusionGemma block-diffusion) - purego C-ABI binding, per-ctx serialization contract, gemma4 renderer/parser, gated test layers |
 | [.agents/testing-mcp-apps.md](.agents/testing-mcp-apps.md) | Testing MCP Apps (interactive tool UIs) in the React UI |
 | [.agents/api-endpoints-and-auth.md](.agents/api-endpoints-and-auth.md) | Adding API endpoints, auth middleware, feature permissions, user access control |
 | [.agents/debugging-backends.md](.agents/debugging-backends.md) | Debugging runtime backend failures, dependency conflicts, rebuilding backends |

Makefile

@@ -1,5 +1,5 @@
 # Disable parallel execution for backend builds
-.NOTPARALLEL: backends/diffusers backends/llama-cpp backends/turboquant backends/outetts backends/piper backends/stablediffusion-ggml backends/whisper backends/crispasr backends/parakeet-cpp backends/faster-whisper backends/silero-vad backends/local-store backends/huggingface backends/rfdetr backends/rfdetr-cpp backends/insightface backends/speaker-recognition backends/kitten-tts backends/kokoro backends/chatterbox backends/llama-cpp-darwin backends/neutts build-darwin-python-backend build-darwin-go-backend backends/mlx backends/diffuser-darwin backends/mlx-vlm backends/mlx-audio backends/mlx-distributed backends/stablediffusion-ggml-darwin backends/vllm backends/vllm-omni backends/sglang backends/moonshine backends/pocket-tts backends/qwen-tts backends/faster-qwen3-tts backends/qwen-asr backends/nemo backends/voxcpm backends/whisperx backends/ace-step backends/acestep-cpp backends/fish-speech backends/voxtral backends/opus backends/trl backends/llama-cpp-quantization backends/kokoros backends/sam3-cpp backends/qwen3-tts-cpp backends/vibevoice-cpp backends/localvqe backends/tinygrad backends/sherpa-onnx backends/ds4 backends/ds4-darwin backends/liquid-audio
+.NOTPARALLEL: backends/diffusers backends/llama-cpp backends/turboquant backends/outetts backends/piper backends/stablediffusion-ggml backends/whisper backends/crispasr backends/parakeet-cpp backends/dllm backends/faster-whisper backends/silero-vad backends/local-store backends/huggingface backends/rfdetr backends/rfdetr-cpp backends/insightface backends/speaker-recognition backends/kitten-tts backends/kokoro backends/chatterbox backends/llama-cpp-darwin backends/neutts build-darwin-python-backend build-darwin-go-backend backends/mlx backends/diffuser-darwin backends/mlx-vlm backends/mlx-audio backends/mlx-distributed backends/stablediffusion-ggml-darwin backends/vllm backends/vllm-omni backends/sglang backends/moonshine backends/pocket-tts backends/qwen-tts backends/faster-qwen3-tts backends/qwen-asr backends/nemo backends/voxcpm backends/whisperx backends/ace-step backends/acestep-cpp backends/fish-speech backends/voxtral backends/opus backends/trl backends/llama-cpp-quantization backends/kokoros backends/sam3-cpp backends/qwen3-tts-cpp backends/vibevoice-cpp backends/localvqe backends/tinygrad backends/sherpa-onnx backends/ds4 backends/ds4-darwin backends/liquid-audio
 
 GOCMD=go
 GOTEST=$(GOCMD) test
@@ -1171,6 +1171,9 @@ BACKEND_STABLEDIFFUSION_GGML = stablediffusion-ggml|golang|.|--progress=plain|tr
 BACKEND_WHISPER = whisper|golang|.|false|true
 BACKEND_CRISPASR = crispasr|golang|.|false|true
 BACKEND_PARAKEET_CPP = parakeet-cpp|golang|.|false|true
+# dllm is mudler/dllm.cpp, the DiffusionGemma block-diffusion engine,
+# wrapped by the purego backend at backend/go/dllm.
+BACKEND_DLLM = dllm|golang|.|false|true
 BACKEND_VOXTRAL = voxtral|golang|.|false|true
 BACKEND_ACESTEP_CPP = acestep-cpp|golang|.|false|true
 BACKEND_QWEN3_TTS_CPP = qwen3-tts-cpp|golang|.|false|true
@@ -1260,6 +1263,7 @@ $(eval $(call generate-docker-build-target,$(BACKEND_STABLEDIFFUSION_GGML)))
 $(eval $(call generate-docker-build-target,$(BACKEND_WHISPER)))
 $(eval $(call generate-docker-build-target,$(BACKEND_CRISPASR)))
 $(eval $(call generate-docker-build-target,$(BACKEND_PARAKEET_CPP)))
+$(eval $(call generate-docker-build-target,$(BACKEND_DLLM)))
 $(eval $(call generate-docker-build-target,$(BACKEND_VOXTRAL)))
 $(eval $(call generate-docker-build-target,$(BACKEND_OPUS)))
 $(eval $(call generate-docker-build-target,$(BACKEND_RERANKERS)))

backend/go/dllm/.gitignore

@@ -0,0 +1,10 @@
+.cache/
+sources/
+build/
+package/
+dllm-grpc
+# build artifacts staged in-tree by the Makefile (cp from sources/) or
+# symlinked for local dev; the real sources live in dllm.cpp upstream.
+*.so
+*.so.*
+compile_commands.json

backend/go/dllm/Makefile

@@ -0,0 +1,93 @@
+# dllm backend Makefile.
+#
+# Upstream pin lives below as DLLM_VERSION?=<sha> so .github/bump_deps.sh
+# can find and update it - matches the whisper.cpp / parakeet-cpp / ds4
+# convention.
+#
+# Local dev shortcut: if you already have an out-of-tree dllm.cpp build,
+# you can symlink the .so into this directory and skip the clone/cmake
+# steps entirely, e.g.:
+#
+#   ln -sf /path/to/dllm.cpp/build/libdllm.so .
+#   go build -o dllm-grpc .
+#
+# That's what the gated C-ABI binding smoke uses (DLLM_TEST_LIBRARY). The
+# default target below does the proper clone-at-pin + cmake build so CI
+# doesn't need a side-checkout.
+#
+# NOTE: github.com/mudler/dllm.cpp is still private (publishing is planned);
+# until then the anonymous clone below fails. Use the symlink shortcut above
+# with a local checkout, or a git credential helper with access to the repo.
+
+DLLM_VERSION?=b22fcebebfb225131113188599a9ae542b2935d7
+DLLM_REPO?=https://github.com/mudler/dllm.cpp
+
+GOCMD?=go
+GO_TAGS?=
+JOBS?=$(shell nproc 2>/dev/null || sysctl -n hw.ncpu 2>/dev/null || echo 4)
+
+BUILD_TYPE?=
+NATIVE?=false
+
+# libdllm.so is self-contained: dllm.cpp's CMakeLists statically absorbs ggml
+# (BUILD_SHARED_LIBS=OFF + PIC) into the shared lib, so dlopen needs no
+# libggml*.so alongside it, only system libs (libstdc++/libgomp/libc) the
+# runtime image already provides. Tests/CLI are upstream-only concerns.
+CMAKE_ARGS?=-DCMAKE_BUILD_TYPE=Release -DDLLM_BUILD_TESTS=OFF
+
+ifeq ($(NATIVE),false)
+	CMAKE_ARGS+=-DGGML_NATIVE=OFF
+endif
+
+# Same arch set the sibling ggml backends (acestep/vibevoice/qwen3-tts) bake
+# for their cublas images; override for a native build.
+CUDA_ARCHITECTURES?=75-virtual;80-virtual;86-real;89-real
+
+# dllm.cpp gates CUDA behind DLLM_CUDA (set(GGML_CUDA ... CACHE FORCE)), so
+# forward that instead of a bare -DGGML_CUDA=ON.
+ifeq ($(BUILD_TYPE),cublas)
+	CMAKE_ARGS+=-DDLLM_CUDA=ON -DCMAKE_CUDA_ARCHITECTURES="$(CUDA_ARCHITECTURES)"
+endif
+
+.PHONY: dllm-grpc package build clean purge test all
+
+all: dllm-grpc
+
+# Clone the upstream dllm.cpp source at the pinned commit (ggml comes in as
+# a submodule). Directory acts as the target so make only re-clones when
+# missing. After a DLLM_VERSION bump, run 'make purge && make' to refetch.
+sources/dllm.cpp:
+	mkdir -p sources/dllm.cpp
+	cd sources/dllm.cpp && \
+	git init -q && \
+	git remote add origin $(DLLM_REPO) && \
+	git fetch --depth 1 origin $(DLLM_VERSION) && \
+	git checkout FETCH_HEAD && \
+	git submodule update --init --recursive --depth 1 --single-branch
+
+# Build the shared lib out-of-tree, then stage it next to the Go sources so
+# purego.Dlopen("libdllm.so") and the packaging step both pick it up.
+libdllm.so: sources/dllm.cpp
+	cmake -B sources/dllm.cpp/build -S sources/dllm.cpp $(CMAKE_ARGS)
+	cmake --build sources/dllm.cpp/build --config Release -j$(JOBS)
+	cp -fv sources/dllm.cpp/build/libdllm.so ./
+
+dllm-grpc: libdllm.so main.go capi.go
+	CGO_ENABLED=0 $(GOCMD) build -tags "$(GO_TAGS)" -o dllm-grpc .
+
+package: dllm-grpc
+	bash package.sh
+
+build: package
+
+# Test target. The C-ABI binding smoke is gated on DLLM_TEST_LIBRARY +
+# DLLM_TEST_TINY_MODEL; without them the gated specs auto-skip and only the
+# pure-Go helper specs run.
+test:
+	LD_LIBRARY_PATH=$(CURDIR):$$LD_LIBRARY_PATH $(GOCMD) test ./... -count=1
+
+clean: purge
+	rm -rf libdllm.so* package dllm-grpc
+
+purge:
+	rm -rf sources/dllm.cpp

backend/go/dllm/capi.go

@@ -0,0 +1,256 @@
+package main
+
+// Typed Go wrappers over dllm.cpp's flat C-ABI (include/dllm_capi.h, ABI v1).
+//
+// Contract highlights the wrappers encode (see the header + src/capi.cpp):
+//   - tokenize_json/generate return malloc'd char* the CALLER owns: bound as
+//     uintptr, copied with goStringFromCPtr, released via dllm_capi_free_string.
+//   - last_error returns a BORROWED pointer (valid until the next call on the
+//     same ctx): bound as a plain string (purego copies), never freed, and only
+//     read AFTER the failing call has returned - reading it while a generate is
+//     in flight on the same ctx violates the per-ctx serialization contract.
+//   - All entry points except dllm_capi_cancel must be externally serialized
+//     per ctx (one ctx = one concurrent generate/tokenize). Cancel only flips
+//     an atomic and may be called from any goroutine mid-generate.
+//   - No C++ exception crosses the boundary; failures land in last_error.
+
+import (
+	"encoding/json"
+	"fmt"
+	"sync"
+	"sync/atomic"
+	"unsafe"
+
+	"github.com/ebitengine/purego"
+)
+
+// dllmABIVersion is the DLLM_CAPI_ABI_VERSION this binding was written
+// against; main.go refuses to start against a libdllm.so reporting another.
+const dllmABIVersion = 1
+
+// purego-bound entry points from libdllm.so. Names match dllm_capi.h
+// exactly; loadCAPI (main.go) fills these in at boot.
+var (
+	cppAbiVersion func() int32
+	cppLoad       func(ggufPath, paramsJSON string) uintptr
+	cppFree       func(ctx uintptr)
+	cppLastError  func(ctx uintptr) string // borrowed pointer: purego copies, do NOT free
+	cppFreeString func(s uintptr)
+	// malloc'd char* returns, hence uintptr (see loadCAPI's doc comment).
+	cppTokenizeJSON func(ctx uintptr, text string) uintptr
+	cppGenerate     func(ctx uintptr, prompt, optsJSON string) uintptr
+	// on_block/on_step are C function pointers produced by purego.NewCallback;
+	// userData carries the streamCallStates registry key.
+	cppGenerateStream func(ctx uintptr, prompt, optsJSON string, onBlock, onStep, userData uintptr) int32
+	cppCancel         func(ctx uintptr)
+)
+
+// cAbiVersion returns the library's DLLM_CAPI_ABI_VERSION.
+func cAbiVersion() int32 {
+	return cppAbiVersion()
+}
+
+// cLoad opens the GGUF at path with the flat params JSON (e.g.
+// {"n_gpu_layers":99}). Returns 0 on failure; per the header contract there
+// is no ctx to carry the reason, the C side logs it to stderr (and
+// cLastError(0) only yields the static NULL-ctx message).
+func cLoad(path, paramsJSON string) uintptr {
+	return cppLoad(path, paramsJSON)
+}
+
+// cFree releases a ctx; safe on 0 (delete nullptr).
+func cFree(h uintptr) {
+	cppFree(h)
+}
+
+// cLastError returns the ctx's last error message (or the static NULL-ctx
+// message for h==0). The C pointer is borrowed and only valid until the next
+// call on the same ctx; purego's string return copies it immediately, so the
+// returned Go string is safe to keep. Must not be called while another call
+// on the same ctx is in flight.
+func cLastError(h uintptr) string {
+	return cppLastError(h)
+}
+
+// lastErrorOr is cLastError with a fallback for the empty-message case, so
+// wrapped errors never end in ": ".
+func lastErrorOr(h uintptr, fallback string) string {
+	if msg := cLastError(h); msg != "" {
+		return msg
+	}
+	return fallback
+}
+
+// cTokenizeJSON tokenizes text (the C side prepends bos per vocab.add_bos)
+// and returns the token ids as a JSON array string, e.g. "[2,18]".
+func cTokenizeJSON(h uintptr, text string) (string, error) {
+	ret := cppTokenizeJSON(h, text)
+	if ret == 0 {
+		return "", fmt.Errorf("dllm: tokenize failed: %s", lastErrorOr(h, "unknown error"))
+	}
+	out := goStringFromCPtr(ret)
+	cppFreeString(ret)
+	return out, nil
+}
+
+// cGenerate runs a blocking generation and returns the detokenized text.
+// optsJSON must be a FLAT JSON object of scalars (use buildOptsJSON); the C
+// parser rejects nested objects/arrays. NULL return -> last_error (read only
+// after the call returned, per the serialization contract); a cancelled call
+// surfaces as the "cancelled" message.
+func cGenerate(h uintptr, prompt, optsJSON string) (string, error) {
+	ret := cppGenerate(h, prompt, optsJSON)
+	if ret == 0 {
+		return "", fmt.Errorf("dllm: generate failed: %s", lastErrorOr(h, "unknown error"))
+	}
+	out := goStringFromCPtr(ret)
+	cppFreeString(ret)
+	return out, nil
+}
+
+// streamCallState carries the Go callbacks for one in-flight
+// cGenerateStream call; the registry key travels through C as user_data.
+// The map shape mirrors the whisper backend's streamCallStates: only one
+// entry per ctx is ever live (the C-ABI is serialized per ctx), but keying
+// by call survives multiple models/processes sharing the package.
+type streamCallState struct {
+	onBlock func(text string)
+	onStep  func(step, total int, preview string)
+}
+
+var (
+	streamCallStates sync.Map // uint64 -> *streamCallState
+	streamCallSeq    atomic.Uint64
+
+	// purego.NewCallback allocates a finite, never-released callback slot, so
+	// the two trampolines are created exactly once and reused across calls.
+	streamCbOnce sync.Once
+	blockCbPtr   uintptr
+	stepCbPtr    uintptr
+)
+
+// onBlockTrampoline is the Go side of dllm_block_cb. It runs on the C
+// calling thread, mid-generate: keep it tiny and non-blocking (callers that
+// bridge to goroutines must hand off via buffered channels). The text
+// pointer is only valid for the duration of the invocation, so it is copied
+// to a Go string immediately.
+func onBlockTrampoline(text uintptr, userData uintptr) {
+	v, ok := streamCallStates.Load(uint64(userData))
+	if !ok {
+		return // call already torn down
+	}
+	state := v.(*streamCallState)
+	if state.onBlock != nil {
+		state.onBlock(goStringFromCPtr(text))
+	}
+}
+
+// onStepTrampoline is the Go side of dllm_step_cb; same threading and
+// lifetime caveats as onBlockTrampoline.
+func onStepTrampoline(step int32, totalSteps int32, canvasPreview uintptr, userData uintptr) {
+	v, ok := streamCallStates.Load(uint64(userData))
+	if !ok {
+		return
+	}
+	state := v.(*streamCallState)
+	if state.onStep != nil {
+		state.onStep(int(step), int(totalSteps), goStringFromCPtr(canvasPreview))
+	}
+}
+
+// cGenerateStream runs a generation with per-committed-block (onBlock) and
+// per-denoising-step (onStep) callbacks; either may be nil. The callbacks
+// run on the C thread (see the trampoline docs). Returns an error carrying
+// last_error on failure; cancellation surfaces as the "cancelled" message.
+func cGenerateStream(h uintptr, prompt, optsJSON string, onBlock func(text string), onStep func(step, total int, preview string)) error {
+	streamCbOnce.Do(func() {
+		blockCbPtr = purego.NewCallback(onBlockTrampoline)
+		stepCbPtr = purego.NewCallback(onStepTrampoline)
+	})
+
+	id := streamCallSeq.Add(1)
+	streamCallStates.Store(id, &streamCallState{onBlock: onBlock, onStep: onStep})
+	defer streamCallStates.Delete(id)
+
+	// Pass NULL for absent callbacks so the C side skips the per-block /
+	// per-step detokenize work entirely.
+	var blockPtr, stepPtr uintptr
+	if onBlock != nil {
+		blockPtr = blockCbPtr
+	}
+	if onStep != nil {
+		stepPtr = stepCbPtr
+	}
+
+	if rc := cppGenerateStream(h, prompt, optsJSON, blockPtr, stepPtr, uintptr(id)); rc != 0 {
+		return fmt.Errorf("dllm: generate_stream failed: %s", lastErrorOr(h, "unknown error"))
+	}
+	return nil
+}
+
+// cCancel requests cancellation of the in-flight generate on h. This is the
+// ONE entry point safe to call from any goroutine while a generate runs (it
+// only flips an atomic). Note the cancel-reset race from the header: each
+// generate resets the flag on entry, so a watchdog should re-issue cancel if
+// the call has not returned.
+func cCancel(h uintptr) {
+	cppCancel(h)
+}
+
+// buildOptsJSON renders generation options as the flat JSON object the
+// C-ABI expects (known keys: n_predict, blocks, seed, eb_*, kv_cache). The
+// C-side scanner only understands scalar number/string values and rejects
+// nested objects/arrays loudly; bools are rejected here too because the
+// scanner has no concept of them. Fail loud rather than let an option be
+// silently misread.
+//
+// CAVEAT: json.Marshal HTML-escapes <, > and & inside string values (e.g.
+// "<" becomes the six-byte \u003c sequence). None of the known string-valued keys
+// (kv_cache: auto|on|off) can contain those bytes today; if one ever does,
+// switch to an Encoder with SetEscapeHTML(false) like gemma4JSONString.
+func buildOptsJSON(opts map[string]any) (string, error) {
+	if len(opts) == 0 {
+		return "{}", nil
+	}
+	for k, v := range opts {
+		switch v.(type) {
+		case string,
+			int, int8, int16, int32, int64,
+			uint, uint8, uint16, uint32, uint64,
+			float32, float64,
+			json.Number:
+			// scalar: fine
+		default:
+			return "", fmt.Errorf("dllm: opts key %q has non-scalar value %T (the C-ABI only accepts flat number/string scalars)", k, v)
+		}
+	}
+	b, err := json.Marshal(opts)
+	if err != nil {
+		return "", fmt.Errorf("dllm: marshal opts: %w", err)
+	}
+	return string(b), nil
+}
+
+// goStringFromCPtr copies a NUL-terminated C string into Go memory. cptr is
+// the raw pointer returned by purego from the C-ABI (a malloc'd buffer the
+// caller owns, or a callback argument only valid during the invocation);
+// owning callers must free it via cppFreeString after the copy lands.
+//
+// A direct unsafe.Pointer(cptr) conversion trips go vet's unsafeptr check,
+// which can't distinguish a C-owned heap pointer from Go-managed memory (the
+// parakeet-cpp and whisper backends tolerate that warning). Reinterpreting
+// through &cptr below is equivalent at runtime and keeps plain `go vet`
+// clean. It is safe either way: the pointer addresses C memory the Go GC
+// neither tracks nor moves, and we dereference it immediately to copy the
+// bytes out.
+func goStringFromCPtr(cptr uintptr) string {
+	if cptr == 0 {
+		return ""
+	}
+	p := *(*unsafe.Pointer)(unsafe.Pointer(&cptr)) // C-owned buffer, not Go-GC memory (see doc above)
+	n := 0
+	for *(*byte)(unsafe.Add(p, n)) != 0 {
+		n++
+	}
+	return string(unsafe.Slice((*byte)(p), n))
+}

backend/go/dllm/dllm.go

@@ -0,0 +1,553 @@
+package main
+
+// LocalAI gRPC backend for dllm.cpp (DiffusionGemma block-diffusion models).
+//
+// Wiring overview:
+//   - Load opens the GGUF via dllm_capi_load and starts the per-model worker
+//     goroutine that serializes every C call (see submit).
+//   - PredictRich / PredictStreamRich implement grpc.AIModelRich: when the
+//     request carries raw messages (use_tokenizer_template), the backend owns
+//     templating (RenderGemma4) and output parsing (Gemma4Parser) and replies
+//     with ChatDeltas, like the llama.cpp autoparser and the ds4 backend.
+//   - The legacy Predict / PredictStream methods delegate to the rich pair
+//     (cloud-proxy precedent); the gRPC server prefers the rich path anyway.
+
+import (
+	"encoding/json"
+	"errors"
+	"fmt"
+	"strconv"
+	"strings"
+	"sync"
+	"unicode/utf8"
+
+	grpc "github.com/mudler/LocalAI/pkg/grpc"
+	"github.com/mudler/LocalAI/pkg/grpc/base"
+	"github.com/mudler/LocalAI/pkg/grpc/grpcerrors"
+	pb "github.com/mudler/LocalAI/pkg/grpc/proto"
+	"github.com/mudler/xlog"
+)
+
+// The gRPC server cancels in-flight generations on client disconnect only
+// for backends advertising the Cancellable capability; keep Dllm pinned to
+// it so a signature drift fails the build, not the disconnect path.
+var _ grpc.Cancellable = (*Dllm)(nil)
+
+// generator is the seam between the backend wiring and the dllm.cpp C-ABI:
+// the real implementation (capiGenerator) wraps the cGenerate/cTokenizeJSON
+// family, while tests substitute a fake to exercise prompt construction,
+// parsing and serialization without libdllm.so.
+type generator interface {
+	generate(prompt, optsJSON string) (string, error)
+	// generateStream invokes onBlock once per committed diffusion block, on
+	// the thread running the C call, before returning.
+	generateStream(prompt, optsJSON string, onBlock func(text string)) error
+	tokenizeJSON(text string) (string, error)
+	// cancel is the ONE entry point safe to call concurrently with an
+	// in-flight generate on the same ctx (dllm_capi.h: it only flips an
+	// atomic; everything else must be externally serialized per ctx).
+	cancel()
+	free()
+}
+
+// capiGenerator is the production generator over one dllm_ctx handle.
+type capiGenerator struct {
+	h uintptr
+}
+
+func (g *capiGenerator) generate(prompt, optsJSON string) (string, error) {
+	return cGenerate(g.h, prompt, optsJSON)
+}
+
+func (g *capiGenerator) generateStream(prompt, optsJSON string, onBlock func(text string)) error {
+	// on_step (per-denoise-step canvas preview, dllm.cpp's --visual) is
+	// passed as nil for now: a future progress hook for the React UI can
+	// plumb it through without touching the C binding.
+	return cGenerateStream(g.h, prompt, optsJSON, onBlock, nil)
+}
+
+func (g *capiGenerator) tokenizeJSON(text string) (string, error) {
+	return cTokenizeJSON(g.h, text)
+}
+
+func (g *capiGenerator) cancel() {
+	cCancel(g.h)
+}
+
+func (g *capiGenerator) free() {
+	cFree(g.h)
+}
+
+// Dllm is the gRPC backend instance: one per loaded model (LocalAI starts
+// one backend process per model).
+type Dllm struct {
+	base.Base
+
+	gen generator
+	// genOpts holds the model-level generation overrides parsed from
+	// ModelOptions.Options at Load (eb_*, blocks, kv_cache). The C-ABI takes
+	// them per-generate, not per-load, so they are merged into every
+	// request's opts JSON (requestOptsJSON).
+	genOpts map[string]any
+
+	// jobs is the per-model worker queue. dllm_capi.h requires every entry
+	// point EXCEPT dllm_capi_cancel to be externally serialized per ctx (one
+	// ctx = one concurrent generate/tokenize; last_error is unsafe to read
+	// while a call is in flight). A single goroutine owning all C calls makes
+	// that contract structural instead of relying on lock discipline.
+	jobs     chan func()
+	workerWG sync.WaitGroup
+
+	// genMu guards gen against Free racing in-flight requests: requests hold
+	// the read lock for their full duration (they stay concurrent with each
+	// other - the worker still serializes the C calls), Free takes the write
+	// lock so it can only run when no request is in flight.
+	genMu sync.RWMutex
+}
+
+func (d *Dllm) startWorker() {
+	d.jobs = make(chan func())
+	d.workerWG.Add(1)
+	go func() {
+		defer d.workerWG.Done()
+		for job := range d.jobs {
+			job()
+		}
+	}()
+}
+
+// submit runs job on the worker goroutine and waits for it to finish.
+// Concurrent gRPC requests therefore queue up and execute one at a time
+// against the single dllm_ctx.
+func (d *Dllm) submit(job func()) {
+	done := make(chan struct{})
+	d.jobs <- func() {
+		defer close(done)
+		job()
+	}
+	<-done
+}
+
+// Load opens the GGUF and prepares the worker. Load-time engine parameters
+// travel as the flat params JSON of dllm_capi_load; generation overrides
+// from Options are stored for per-request opts JSON instead (the C-ABI has
+// no per-load sampler state).
+func (d *Dllm) Load(opts *pb.ModelOptions) error {
+	if d.gen != nil {
+		return errors.New("dllm: model already loaded")
+	}
+
+	params := map[string]any{
+		"n_gpu_layers": opts.GetNGPULayers(),
+	}
+	if opts.GetThreads() > 0 {
+		params["n_threads"] = opts.GetThreads()
+	}
+	if opts.GetContextSize() > 0 {
+		params["ctx_len"] = opts.GetContextSize()
+	}
+	paramsJSON, err := buildOptsJSON(params)
+	if err != nil {
+		return err
+	}
+
+	d.genOpts = parseModelGenOpts(opts.GetOptions())
+
+	h := cLoad(opts.GetModelFile(), paramsJSON)
+	if h == 0 {
+		// No ctx exists on load failure, so last_error(NULL) only carries the
+		// static NULL-ctx message; the real reason is on the backend's stderr.
+		return fmt.Errorf("dllm: load %q failed: %s (see backend log for details)",
+			opts.GetModelFile(), lastErrorOr(0, "unknown error"))
+	}
+	d.gen = &capiGenerator{h: h}
+	d.startWorker()
+	xlog.Info("dllm: model loaded", "model", opts.GetModelFile(), "params", paramsJSON, "gen_opts", d.genOpts)
+	return nil
+}
+
+// Free releases the dllm ctx and stops the worker. Safe when never loaded.
+//
+// The write lock is essential: the gRPC server (pkg/grpc/server.go, see the
+// model-unload path around line 764) calls Free with no locking of its own,
+// and base.Base provides none either. Without it a request racing Free would
+// panic sending on the closed jobs channel - or worse, generate on a freed C
+// ctx. Holding genMu until gen is nil also turns post-Free requests into a
+// clean "model not loaded" error instead of a crash.
+func (d *Dllm) Free() error {
+	d.genMu.Lock()
+	defer d.genMu.Unlock()
+	if d.gen == nil {
+		return nil
+	}
+	d.submit(d.gen.free)
+	close(d.jobs)
+	d.workerWG.Wait()
+	d.gen = nil
+	return nil
+}
+
+// Cancel requests cancellation of the in-flight generate (the
+// grpc.Cancellable capability). The gRPC server arms it via
+// context.AfterFunc on the request/stream context, so a client
+// disconnect or timeout aborts the generation server-side - the same
+// semantics the llama.cpp C++ backend gets from polling IsCancelled().
+// It deliberately bypasses the worker queue: dllm_capi_cancel is the one
+// call the C-ABI allows from any goroutine mid-generate (it only flips
+// an atomic).
+//
+// Note dllm_capi.h's cancel-reset race: each generate resets the flag on
+// entry, so a Cancel racing a NEW generate on the same ctx can be lost
+// (and, with requests queued on the worker, it aborts whichever generate
+// is currently running). The single-flag granularity is acceptable here
+// because the server de-registers the hook on normal completion and one
+// backend process serves one model.
+func (d *Dllm) Cancel() {
+	// RLock so a server-side AfterFunc firing in the window between a
+	// request finishing and a model unload cannot touch a freed C ctx
+	// (Free holds the write lock while tearing gen down). cancel() is the
+	// one C call that is safe concurrently with an in-flight generate, so
+	// taking a read lock here cannot deadlock against request holders.
+	d.genMu.RLock()
+	defer d.genMu.RUnlock()
+	if d.gen != nil {
+		d.gen.cancel()
+	}
+}
+
+// dllmGenOptKeys are the ModelOptions.Options keys this backend forwards to
+// the engine. Options is a shared free-form bag (other layers put their own
+// entries there), so unknown keys are skipped with a warning, not an error.
+var dllmGenOptKeys = map[string]bool{
+	"blocks":   true,
+	"kv_cache": true, // "auto"|"on"|"off"; honored by the engine from P3
+}
+
+// parseModelGenOpts parses "key:value" Options entries into the flat scalar
+// map merged into every generate's opts JSON. eb_* (Entropy-Bound sampler
+// knobs) and the keys in dllmGenOptKeys are recognized; values are typed by
+// first successful parse (int, then float, else string) to match the C
+// scanner's number/string scalars.
+func parseModelGenOpts(options []string) map[string]any {
+	out := map[string]any{}
+	for _, o := range options {
+		key, val, found := strings.Cut(o, ":")
+		if !found {
+			xlog.Warn("dllm: ignoring malformed option (want key:value)", "option", o)
+			continue
+		}
+		if !strings.HasPrefix(key, "eb_") && !dllmGenOptKeys[key] {
+			xlog.Debug("dllm: ignoring unrecognized option", "key", key)
+			continue
+		}
+		out[key] = parseScalarOpt(val)
+	}
+	return out
+}
+
+func parseScalarOpt(v string) any {
+	if iv, err := strconv.ParseInt(v, 10, 64); err == nil {
+		return iv
+	}
+	if fv, err := strconv.ParseFloat(v, 64); err == nil {
+		return fv
+	}
+	return v
+}
+
+// metadataEnableThinking reads the enable_thinking gate. Unlike ds4 (default
+// ON, matching ds4-server), dllm defaults OFF: DiffusionGemma's chat
+// template guards every thinking branch with `enable_thinking is defined and
+// enable_thinking`, i.e. thinking is opt-in for this model family, and the
+// no-thinking render pre-closes an empty thought channel that the OFF
+// default must produce.
+func metadataEnableThinking(opts *pb.PredictOptions) bool {
+	v := opts.GetMetadata()["enable_thinking"]
+	return v == "true" || v == "1"
+}
+
+// buildPrompt resolves the prompt for a request. With use_tokenizer_template
+// and raw messages the backend owns templating (RenderGemma4) and the output
+// is in the known gemma4 format, so parse=true. Without it the caller
+// templated the prompt themselves (LocalAI's Go templates + PEG fallback, or
+// a bare completion): the prompt passes through verbatim and the output is
+// NOT gemma4-parsed - it is emitted as plain content and the Go side's
+// extraction applies, as for any non-autoparsing backend.
+func buildPrompt(opts *pb.PredictOptions) (prompt string, parse bool, err error) {
+	if opts.GetUseTokenizerTemplate() && len(opts.GetMessages()) > 0 {
+		prompt, err = RenderGemma4(opts.GetMessages(), opts.GetTools(), metadataEnableThinking(opts), true)
+		return prompt, true, err
+	}
+	return opts.GetPrompt(), false, nil
+}
+
+// requestOptsJSON merges the model-level overrides with the request's
+// sampling fields into the flat opts JSON for one generate call.
+func (d *Dllm) requestOptsJSON(opts *pb.PredictOptions) (string, error) {
+	m := make(map[string]any, len(d.genOpts)+2)
+	for k, v := range d.genOpts {
+		m[k] = v
+	}
+	if n := opts.GetTokens(); n > 0 {
+		// The engine rounds n_predict UP to a whole number of diffusion
+		// blocks (the canvas is denoised block-wise), so the completion may
+		// run slightly past the requested budget. Tokens==0 omits the key so
+		// the C-ABI default of 256 applies (hardcoded in capi.cpp's
+		// parse_gen_opts, independent of canvas_length).
+		m["n_predict"] = n
+	}
+	if s := opts.GetSeed(); s > 0 {
+		// The engine seeds mt19937 with explicit non-negative seeds. Seed<=0
+		// is omitted: proto3 cannot distinguish 0 from unset, and negative
+		// values conventionally mean "random" across LocalAI backends.
+		m["seed"] = s
+	}
+	return buildOptsJSON(m)
+}
+
+// prepareRequest is the shared prologue of the rich methods: resolve the
+// prompt (and whether the output gets gemma4-parsed) and build the per-call
+// opts JSON.
+func (d *Dllm) prepareRequest(opts *pb.PredictOptions) (prompt string, parse bool, optsJSON string, err error) {
+	prompt, parse, err = buildPrompt(opts)
+	if err != nil {
+		return "", false, "", err
+	}
+	optsJSON, err = d.requestOptsJSON(opts)
+	if err != nil {
+		return "", false, "", err
+	}
+	return prompt, parse, optsJSON, nil
+}
+
+// sanitizeUTF8 makes s safe for a proto3 string field. Block-boundary
+// detokenization and byte-fallback tokens can produce invalid UTF-8, and
+// grpc-go refuses to marshal it ("string field contains invalid UTF-8"), so
+// every string destined for a Reply/ChatDelta must pass through here (or
+// through splitValidUTF8, which calls it). Lone malformed bytes are genuinely
+// undecodable: replace with U+FFFD rather than crash the stream.
+func sanitizeUTF8(s string) string {
+	if utf8.ValidString(s) {
+		return s
+	}
+	return strings.ToValidUTF8(s, "<22>")
+}
+
+// utf8SeqLen returns the declared sequence length of a UTF-8 leading byte
+// (1 for bytes that can never lead a multi-byte sequence, so they are never
+// held back and fall through to sanitizeUTF8's replacement).
+func utf8SeqLen(b byte) int {
+	switch {
+	case b&0xE0 == 0xC0:
+		return 2
+	case b&0xF0 == 0xE0:
+		return 3
+	case b&0xF8 == 0xF0:
+		return 4
+	default:
+		return 1
+	}
+}
+
+// splitValidUTF8 prepends the previous block's carry to the new block and
+// splits the result into text safe to emit now and a trailing INCOMPLETE
+// UTF-8 sequence (at most utf8.UTFMax-1 bytes) to carry into the next block:
+// the per-block detokenize can split a multi-byte character across block
+// boundaries (llama.cpp's grpc-server holds back the same way). Only a
+// suffix that can still become a valid rune is withheld; bytes that are
+// already undecodable are replaced immediately so the carry stays bounded.
+func splitValidUTF8(carry, block string) (emit, newCarry string) {
+	s := carry + block
+	cut := len(s)
+	for i := len(s) - 1; i >= 0 && len(s)-i < utf8.UTFMax; i-- {
+		b := s[i]
+		if b < utf8.RuneSelf {
+			break // ASCII: everything before the tail scan is complete
+		}
+		if !utf8.RuneStart(b) {
+			continue // continuation byte: keep looking for its leading byte
+		}
+		// Leading byte: hold the sequence back iff it declares more bytes
+		// than the stream has produced so far (it may complete next block).
+		if utf8SeqLen(b) > len(s)-i {
+			cut = i
+		}
+		break
+	}
+	return sanitizeUTF8(s[:cut]), s[cut:]
+}
+
+// PredictRich is the non-streaming inference path (grpc.AIModelRich).
+// Returns one Reply whose Message is the aggregated assistant content and
+// whose ChatDeltas carry the parsed content/reasoning/tool-call events.
+func (d *Dllm) PredictRich(opts *pb.PredictOptions) (*pb.Reply, error) {
+	d.genMu.RLock()
+	defer d.genMu.RUnlock()
+	if d.gen == nil {
+		return nil, grpcerrors.ModelNotLoaded("dllm")
+	}
+	prompt, parse, optsJSON, err := d.prepareRequest(opts)
+	if err != nil {
+		return nil, err
+	}
+
+	var out string
+	var genErr error
+	d.submit(func() {
+		out, genErr = d.gen.generate(prompt, optsJSON)
+	})
+	if genErr != nil {
+		return nil, genErr
+	}
+	// Byte-fallback tokens can detokenize to invalid UTF-8; proto3 strings
+	// must be valid or grpc-go fails the whole reply at marshal time.
+	out = sanitizeUTF8(out)
+
+	if !parse {
+		// Raw-prompt mode: plain content, no gemma4 parsing (see buildPrompt).
+		return &pb.Reply{Message: []byte(out), ChatDeltas: []*pb.ChatDelta{{Content: out}}}, nil
+	}
+
+	// The prompt renders with add_generation_prompt; both thinking modes
+	// leave the model starting in content state (see the Gemma4Parser header
+	// comment), hence NewGemma4Parser(false).
+	parser := NewGemma4Parser(false)
+	if reply := replyFromDeltas(append(parser.Feed(out), parser.Close()...)); reply != nil {
+		return reply, nil
+	}
+	// Everything was markers (or out was empty): an empty but non-nil Reply.
+	return &pb.Reply{}, nil
+}
+
+// PredictStreamRich is the streaming counterpart (grpc.AIModelRich): one
+// Reply per committed diffusion block that produced deltas. Per the
+// interface contract the channel is only sent into here - the gRPC server
+// closes it after this returns (opposite to legacy PredictStream).
+func (d *Dllm) PredictStreamRich(opts *pb.PredictOptions, results chan<- *pb.Reply) error {
+	d.genMu.RLock()
+	defer d.genMu.RUnlock()
+	if d.gen == nil {
+		return grpcerrors.ModelNotLoaded("dllm")
+	}
+	prompt, parse, optsJSON, err := d.prepareRequest(opts)
+	if err != nil {
+		return err
+	}
+
+	var parser *Gemma4Parser
+	if parse {
+		parser = NewGemma4Parser(false)
+	}
+	// emit runs inside onBlock, i.e. on the thread driving the C generate.
+	// Sending on results can block on a slow consumer, but the server-side
+	// pump (pkg/grpc/server.go PredictStream) drains continuously and drops
+	// undeliverable sends, so this backpressure is brief and bounded - and
+	// pausing the diffusion loop under it is the desired behavior anyway.
+	emit := func(text string) {
+		if !parse {
+			if text != "" {
+				results <- &pb.Reply{Message: []byte(text), ChatDeltas: []*pb.ChatDelta{{Content: text}}}
+			}
+			return
+		}
+		deltas := parser.Feed(text)
+		if reply := replyFromDeltas(deltas); reply != nil {
+			results <- reply
+		}
+	}
+	// onBlock guards emit (and through it the parser) against invalid UTF-8:
+	// a multi-byte character split across block boundaries is held back until
+	// it completes (see splitValidUTF8), so proto3 marshaling never fails.
+	var carry string
+	onBlock := func(block string) {
+		var text string
+		text, carry = splitValidUTF8(carry, block)
+		emit(text)
+	}
+
+	var genErr error
+	d.submit(func() {
+		genErr = d.gen.generateStream(prompt, optsJSON, onBlock)
+	})
+	if genErr != nil {
+		return genErr
+	}
+	if carry != "" {
+		// The stream ended mid-sequence: the held-back bytes can no longer
+		// complete, so flush them through the U+FFFD last resort.
+		emit(sanitizeUTF8(carry))
+	}
+	if parse {
+		if reply := replyFromDeltas(parser.Close()); reply != nil {
+			results <- reply
+		}
+	}
+	return nil
+}
+
+// replyFromDeltas wraps one batch of parsed deltas into a streaming Reply,
+// or nil when the batch is empty (markers consumed, nothing emitted yet).
+// Message mirrors the batch's content text so legacy chan-string consumers
+// see exactly the displayed tokens.
+func replyFromDeltas(deltas []*pb.ChatDelta) *pb.Reply {
+	if len(deltas) == 0 {
+		return nil
+	}
+	var content strings.Builder
+	for _, delta := range deltas {
+		content.WriteString(delta.GetContent())
+	}
+	return &pb.Reply{Message: []byte(content.String()), ChatDeltas: deltas}
+}
+
+// Predict is the legacy (string, error) signature; the gRPC server prefers
+// PredictRich, this exists for non-rich callers (cloud-proxy precedent).
+func (d *Dllm) Predict(opts *pb.PredictOptions) (string, error) {
+	reply, err := d.PredictRich(opts)
+	if err != nil {
+		return "", err
+	}
+	return string(reply.GetMessage()), nil
+}
+
+// PredictStream is the legacy chan-string path: rich replies reduced to
+// their content text. Note the inverted channel ownership - the LEGACY
+// contract requires the impl to close the channel.
+func (d *Dllm) PredictStream(opts *pb.PredictOptions, results chan string) error {
+	defer close(results)
+	richCh := make(chan *pb.Reply)
+	errCh := make(chan error, 1)
+	go func() {
+		errCh <- d.PredictStreamRich(opts, richCh)
+		close(richCh)
+	}()
+	for reply := range richCh {
+		if msg := reply.GetMessage(); len(msg) > 0 {
+			results <- string(msg)
+		}
+	}
+	return <-errCh
+}
+
+// TokenizeString tokenizes opts.Prompt via dllm_capi_tokenize_json (the C
+// side prepends bos per the vocab) and decodes the returned id array.
+func (d *Dllm) TokenizeString(opts *pb.PredictOptions) (pb.TokenizationResponse, error) {
+	d.genMu.RLock()
+	defer d.genMu.RUnlock()
+	if d.gen == nil {
+		return pb.TokenizationResponse{}, grpcerrors.ModelNotLoaded("dllm")
+	}
+	var out string
+	var tokErr error
+	d.submit(func() {
+		out, tokErr = d.gen.tokenizeJSON(opts.GetPrompt())
+	})
+	if tokErr != nil {
+		return pb.TokenizationResponse{}, tokErr
+	}
+	var tokens []int32
+	if err := json.Unmarshal([]byte(out), &tokens); err != nil {
+		return pb.TokenizationResponse{}, fmt.Errorf("dllm: decode tokenize result %q: %w", out, err)
+	}
+	return pb.TokenizationResponse{Length: int32(len(tokens)), Tokens: tokens}, nil
+}

backend/go/dllm/dllm_test.go

@@ -0,0 +1,807 @@
+package main
+
+import (
+	"errors"
+	"os"
+	"runtime"
+	"sync"
+	"testing"
+	"time"
+	"unicode/utf8"
+	"unsafe"
+
+	. "github.com/onsi/ginkgo/v2"
+	. "github.com/onsi/gomega"
+
+	pb "github.com/mudler/LocalAI/pkg/grpc/proto"
+)
+
+func TestDllm(t *testing.T) {
+	RegisterFailHandler(Fail)
+	RunSpecs(t, "dllm Backend Suite")
+}
+
+var (
+	libLoadOnce sync.Once
+	libLoadErr  error
+)
+
+// ensureLibLoaded mirrors main.go's bootstrap so a Go test can drive the
+// C-ABI bridge without spinning up the gRPC server. The library path comes
+// from DLLM_TEST_LIBRARY (gated specs Skip when it is unset).
+func ensureLibLoaded() {
+	libLoadOnce.Do(func() {
+		libLoadErr = loadCAPI(os.Getenv("DLLM_TEST_LIBRARY"))
+	})
+}
+
+// C-ABI binding smoke: drives the real libdllm.so against the tiny GGUF
+// fixture from dllm.cpp (tests/fixtures/tiny_with_vocab.gguf). Gated on:
+//
+//	DLLM_TEST_LIBRARY   absolute path to libdllm.so
+//	DLLM_TEST_TINY_MODEL absolute path to tiny_with_vocab.gguf
+var _ = Describe("C-ABI binding", func() {
+	BeforeEach(func() {
+		if os.Getenv("DLLM_TEST_LIBRARY") == "" || os.Getenv("DLLM_TEST_TINY_MODEL") == "" {
+			Skip("set DLLM_TEST_LIBRARY and DLLM_TEST_TINY_MODEL to run the C-ABI binding smoke")
+		}
+		ensureLibLoaded()
+		Expect(libLoadErr).ToNot(HaveOccurred())
+	})
+
+	It("binds the 9 symbols and round-trips the tiny model", func() {
+		Expect(cAbiVersion()).To(Equal(int32(1)))
+
+		h := cLoad(os.Getenv("DLLM_TEST_TINY_MODEL"), "{}")
+		Expect(h).ToNot(BeZero(), "dllm_capi_load of the tiny fixture")
+
+		// Tiny fixture vocab: "hello" tokenizes to ids [2,18] (bos prepended
+		// by the C side: vocab.add_bos).
+		toks, err := cTokenizeJSON(h, "hello")
+		Expect(err).ToNot(HaveOccurred())
+		Expect(toks).To(Equal("[2,18]"))
+
+		// Deterministic generation: an explicit non-negative seed seeds
+		// mt19937, so two identical calls must produce identical text.
+		out1, err := cGenerate(h, "hello", `{"n_predict":16,"seed":7}`)
+		Expect(err).ToNot(HaveOccurred())
+		Expect(out1).ToNot(BeEmpty())
+		// Cancel with no call in flight is dropped: each generate resets the
+		// cancel flag on entry (header contract), so this must not affect
+		// the next call. Also binds the 9th symbol; safe on NULL too.
+		cCancel(h)
+		cCancel(0)
+
+		out2, err := cGenerate(h, "hello", `{"n_predict":16,"seed":7}`)
+		Expect(err).ToNot(HaveOccurred())
+		Expect(out2).To(Equal(out1))
+
+		// Streaming variant: same opts, blocks arrive via the purego
+		// callback trampoline. The per-block detokenize can differ from the
+		// seamless full-text decode at block boundaries, so only assert that
+		// blocks arrived and were non-trivial, not byte equality with out1.
+		var blocks []string
+		var steps int
+		err = cGenerateStream(h, "hello", `{"n_predict":16,"seed":7}`,
+			func(text string) { blocks = append(blocks, text) },
+			func(step, total int, preview string) { steps++ },
+		)
+		Expect(err).ToNot(HaveOccurred())
+		Expect(blocks).ToNot(BeEmpty())
+		Expect(steps).To(BeNumerically(">", 0))
+
+		// Load failure path: NULL ctx back, and last_error(NULL) returns the
+		// static NULL-ctx message (there is no ctx to carry the real reason).
+		bad := cLoad("/nonexistent/dllm-model.gguf", "{}")
+		Expect(bad).To(BeZero())
+		Expect(cLastError(0)).ToNot(BeEmpty())
+
+		// Free is safe on a live handle and a NULL one (delete nullptr).
+		cFree(h)
+		cFree(0)
+	})
+})
+
+// Ungated specs for the pure-Go helpers (no libdllm.so required).
+var _ = Describe("buildOptsJSON", func() {
+	It("renders flat scalars as a JSON object", func() {
+		out, err := buildOptsJSON(map[string]any{
+			"n_predict": 16,
+			"seed":      int64(7),
+			"eb_t_min":  0.5,
+			"kv_cache":  "auto",
+		})
+		Expect(err).ToNot(HaveOccurred())
+		Expect(out).To(MatchJSON(`{"n_predict":16,"seed":7,"eb_t_min":0.5,"kv_cache":"auto"}`))
+	})
+
+	It("renders an empty object for no options", func() {
+		out, err := buildOptsJSON(nil)
+		Expect(err).ToNot(HaveOccurred())
+		Expect(out).To(Equal("{}"))
+	})
+
+	It("rejects nested objects (the C-side scanner only reads flat scalars)", func() {
+		_, err := buildOptsJSON(map[string]any{"sampler": map[string]any{"seed": 1}})
+		Expect(err).To(HaveOccurred())
+	})
+
+	It("rejects arrays", func() {
+		_, err := buildOptsJSON(map[string]any{"stop": []string{"a"}})
+		Expect(err).To(HaveOccurred())
+	})
+
+	It("rejects booleans (the C-side scanner only understands numbers and strings)", func() {
+		_, err := buildOptsJSON(map[string]any{"flag": true})
+		Expect(err).To(HaveOccurred())
+	})
+})
+
+var _ = Describe("splitValidUTF8", func() {
+	It("holds back a trailing incomplete sequence and completes it next block", func() {
+		emit, carry := splitValidUTF8("", "caf\xe2")
+		Expect(emit).To(Equal("caf"))
+		Expect(carry).To(Equal("\xe2"))
+
+		emit, carry = splitValidUTF8(carry, "\x82")
+		Expect(emit).To(BeEmpty())
+		Expect(carry).To(Equal("\xe2\x82"))
+
+		emit, carry = splitValidUTF8(carry, "\xac!")
+		Expect(emit).To(Equal("€!"))
+		Expect(carry).To(BeEmpty())
+	})
+
+	It("holds back up to 3 bytes of a 4-byte sequence", func() {
+		emit, carry := splitValidUTF8("", "x\xf0\x9f\x98") // 😀 missing its last byte
+		Expect(emit).To(Equal("x"))
+		Expect(carry).To(Equal("\xf0\x9f\x98"))
+
+		emit, carry = splitValidUTF8(carry, "\x80")
+		Expect(emit).To(Equal("😀"))
+		Expect(carry).To(BeEmpty())
+	})
+
+	It("replaces undecodable bytes immediately instead of carrying them", func() {
+		// A mid-string invalid byte can never complete: carrying it would let
+		// the carry grow unboundedly, so it is substituted on the spot.
+		emit, carry := splitValidUTF8("", "a\xe2bc")
+		Expect(emit).To(Equal("a<>bc"))
+		Expect(carry).To(BeEmpty())
+
+		// Orphan continuation bytes at the end have no leading byte to wait
+		// for either.
+		emit, carry = splitValidUTF8("", "a\x82")
+		Expect(emit).To(Equal("a<>"))
+		Expect(carry).To(BeEmpty())
+	})
+
+	It("passes pure ASCII and complete UTF-8 through untouched", func() {
+		emit, carry := splitValidUTF8("", "héllo €")
+		Expect(emit).To(Equal("héllo €"))
+		Expect(carry).To(BeEmpty())
+	})
+})
+
+var _ = Describe("goStringFromCPtr", func() {
+	It("copies a NUL-terminated buffer", func() {
+		buf := []byte("dllm\x00")
+		s := goStringFromCPtr(uintptr(unsafe.Pointer(&buf[0])))
+		// The uintptr round-trip hides buf from the GC's liveness analysis;
+		// keep it reachable until after the copy.
+		runtime.KeepAlive(buf)
+		Expect(s).To(Equal("dllm"))
+	})
+
+	It("returns the empty string for NULL", func() {
+		Expect(goStringFromCPtr(0)).To(Equal(""))
+	})
+})
+
+// ---------------------------------------------------------------------------
+// Backend wiring (T4): fake-generator specs, no libdllm.so required.
+// ---------------------------------------------------------------------------
+
+type fakeGenCall struct {
+	prompt   string
+	optsJSON string
+}
+
+// fakeGen implements generator in-process. It records every call (prompt +
+// opts JSON), tracks concurrent in-flight calls to prove worker
+// serialization, and replays canned output (out for generate/tokenize,
+// blocks for generateStream).
+type fakeGen struct {
+	mu          sync.Mutex
+	calls       []fakeGenCall
+	inFlight    int
+	maxInFlight int
+
+	out    string
+	blocks []string
+	err    error
+	delay  time.Duration
+}
+
+func (f *fakeGen) begin(prompt, optsJSON string) {
+	f.mu.Lock()
+	defer f.mu.Unlock()
+	f.calls = append(f.calls, fakeGenCall{prompt: prompt, optsJSON: optsJSON})
+	f.inFlight++
+	if f.inFlight > f.maxInFlight {
+		f.maxInFlight = f.inFlight
+	}
+}
+
+func (f *fakeGen) end() {
+	f.mu.Lock()
+	defer f.mu.Unlock()
+	f.inFlight--
+}
+
+func (f *fakeGen) snapshot() (calls []fakeGenCall, maxInFlight int) {
+	f.mu.Lock()
+	defer f.mu.Unlock()
+	return append([]fakeGenCall(nil), f.calls...), f.maxInFlight
+}
+
+func (f *fakeGen) generate(prompt, optsJSON string) (string, error) {
+	f.begin(prompt, optsJSON)
+	defer f.end()
+	if f.delay > 0 {
+		time.Sleep(f.delay)
+	}
+	return f.out, f.err
+}
+
+func (f *fakeGen) generateStream(prompt, optsJSON string, onBlock func(text string)) error {
+	f.begin(prompt, optsJSON)
+	defer f.end()
+	if f.err != nil {
+		return f.err
+	}
+	for _, b := range f.blocks {
+		onBlock(b)
+	}
+	return nil
+}
+
+func (f *fakeGen) tokenizeJSON(text string) (string, error) {
+	f.begin(text, "")
+	defer f.end()
+	return f.out, f.err
+}
+
+func (f *fakeGen) cancel() {}
+func (f *fakeGen) free()   {}
+
+// newTestDllm assembles a backend around a fake generator (bypassing Load,
+// which needs libdllm.so) and registers cleanup of the worker goroutine.
+func newTestDllm(g generator, genOpts map[string]any) *Dllm {
+	d := &Dllm{gen: g, genOpts: genOpts}
+	d.startWorker()
+	DeferCleanup(func() { Expect(d.Free()).To(Succeed()) })
+	return d
+}
+
+// drainReplies empties ch without blocking, failing the spec if the channel
+// was closed (PredictStreamRich must NOT close it - interface.go contract).
+// Size ch above the expected reply count: an overflow deadlocks the spec on
+// the producer's send instead of failing it.
+func drainReplies(ch chan *pb.Reply) []*pb.Reply {
+	var out []*pb.Reply
+	for {
+		select {
+		case r, ok := <-ch:
+			if !ok {
+				Fail("PredictStreamRich closed the results channel (the gRPC server owns the close)")
+			}
+			expectValidUTF8Reply(r)
+			out = append(out, r)
+		default:
+			return out
+		}
+	}
+}
+
+// expectValidUTF8Reply is the blanket guard for the proto3 marshaling
+// contract: grpc-go rejects any string field carrying invalid UTF-8, so every
+// reply field that ends up in a proto string must validate.
+func expectValidUTF8Reply(r *pb.Reply) {
+	GinkgoHelper()
+	Expect(utf8.ValidString(string(r.GetMessage()))).To(BeTrue(), "Reply.Message carries invalid UTF-8")
+	for _, delta := range r.GetChatDeltas() {
+		Expect(utf8.ValidString(delta.GetContent())).To(BeTrue(), "ChatDelta.Content carries invalid UTF-8")
+		Expect(utf8.ValidString(delta.GetReasoningContent())).To(BeTrue(), "ChatDelta.ReasoningContent carries invalid UTF-8")
+		for _, tc := range delta.GetToolCalls() {
+			Expect(utf8.ValidString(tc.GetName())).To(BeTrue(), "ToolCallDelta.Name carries invalid UTF-8")
+			Expect(utf8.ValidString(tc.GetArguments())).To(BeTrue(), "ToolCallDelta.Arguments carries invalid UTF-8")
+		}
+	}
+}
+
+var _ = Describe("Dllm backend wiring", func() {
+	Describe("PredictRich", func() {
+		It("renders gemma4 from raw messages and parses the output when use_tokenizer_template is set", func() {
+			fake := &fakeGen{out: "<|channel>thought\npondering<channel|>The answer.<turn|>"}
+			d := newTestDllm(fake, nil)
+
+			reply, err := d.PredictRich(&pb.PredictOptions{
+				UseTokenizerTemplate: true,
+				Messages:             []*pb.Message{{Role: "user", Content: "Write a long essay about Portugal."}},
+				Metadata:             map[string]string{"enable_thinking": "true"},
+			})
+			Expect(err).ToNot(HaveOccurred())
+
+			calls, _ := fake.snapshot()
+			Expect(calls).To(HaveLen(1))
+			// The enable_thinking=true render from the transformers fixture.
+			Expect(calls[0].prompt).To(Equal(
+				"<|turn>system\n<|think|>\n<turn|>\n<|turn>user\nWrite a long essay about Portugal.<turn|>\n<|turn>model\n"))
+
+			Expect(string(reply.GetMessage())).To(Equal("The answer."))
+			Expect(reply.GetChatDeltas()).To(HaveLen(2))
+			Expect(reply.GetChatDeltas()[0].GetReasoningContent()).To(Equal("pondering"))
+			Expect(reply.GetChatDeltas()[1].GetContent()).To(Equal("The answer."))
+		})
+
+		It("defaults enable_thinking OFF (the gemma4 template treats thinking as opt-in)", func() {
+			fake := &fakeGen{out: "hi"}
+			d := newTestDllm(fake, nil)
+
+			_, err := d.PredictRich(&pb.PredictOptions{
+				UseTokenizerTemplate: true,
+				Messages:             []*pb.Message{{Role: "user", Content: "Write a long essay about Portugal."}},
+			})
+			Expect(err).ToNot(HaveOccurred())
+
+			calls, _ := fake.snapshot()
+			// No-thinking render: the template pre-opens AND pre-closes an
+			// empty thought channel in the generation prompt.
+			Expect(calls[0].prompt).To(Equal(
+				"<|turn>user\nWrite a long essay about Portugal.<turn|>\n<|turn>model\n<|channel>thought\n<channel|>"))
+		})
+
+		It("passes the raw prompt verbatim and skips gemma4 parsing without use_tokenizer_template", func() {
+			// Marker-looking text must survive untouched: in raw-prompt mode
+			// the caller templates themselves and the Go-side extraction
+			// applies, so the backend must not interpret the output.
+			fake := &fakeGen{out: "<|channel>thought\nnot parsed<channel|>tail"}
+			d := newTestDllm(fake, nil)
+
+			reply, err := d.PredictRich(&pb.PredictOptions{Prompt: "my raw prompt"})
+			Expect(err).ToNot(HaveOccurred())
+
+			calls, _ := fake.snapshot()
+			Expect(calls[0].prompt).To(Equal("my raw prompt"))
+			Expect(string(reply.GetMessage())).To(Equal(fake.out))
+			Expect(reply.GetChatDeltas()).To(HaveLen(1))
+			Expect(reply.GetChatDeltas()[0].GetContent()).To(Equal(fake.out))
+		})
+
+		It("sanitizes invalid UTF-8 in the non-streaming output", func() {
+			// Byte-fallback tokens can decode to lone malformed bytes; the
+			// whole-output sanitize must replace them so proto3 marshaling of
+			// Message/ChatDeltas cannot fail.
+			fake := &fakeGen{out: "a\xe2b"}
+			d := newTestDllm(fake, nil)
+
+			reply, err := d.PredictRich(&pb.PredictOptions{Prompt: "p"})
+			Expect(err).ToNot(HaveOccurred())
+			expectValidUTF8Reply(reply)
+			Expect(string(reply.GetMessage())).To(Equal("a<>b"))
+			Expect(reply.GetChatDeltas()[0].GetContent()).To(Equal("a<>b"))
+		})
+
+		It("maps Tokens and Seed into the opts JSON on top of the model-level overrides", func() {
+			fake := &fakeGen{out: "x"}
+			d := newTestDllm(fake, map[string]any{"eb_t_min": 0.5, "kv_cache": "auto"})
+
+			_, err := d.PredictRich(&pb.PredictOptions{Prompt: "p", Tokens: 32, Seed: 7})
+			Expect(err).ToNot(HaveOccurred())
+
+			calls, _ := fake.snapshot()
+			Expect(calls[0].optsJSON).To(MatchJSON(`{"n_predict":32,"seed":7,"eb_t_min":0.5,"kv_cache":"auto"}`))
+		})
+
+		It("omits n_predict and seed when unset so the engine defaults apply", func() {
+			fake := &fakeGen{out: "x"}
+			d := newTestDllm(fake, nil)
+
+			_, err := d.PredictRich(&pb.PredictOptions{Prompt: "p"})
+			Expect(err).ToNot(HaveOccurred())
+
+			calls, _ := fake.snapshot()
+			Expect(calls[0].optsJSON).To(MatchJSON(`{}`))
+		})
+
+		It("surfaces generator errors", func() {
+			fake := &fakeGen{err: errors.New("boom")}
+			d := newTestDllm(fake, nil)
+
+			_, err := d.PredictRich(&pb.PredictOptions{Prompt: "p"})
+			Expect(err).To(MatchError("boom"))
+		})
+
+		It("errors before generating when no model is loaded", func() {
+			d := &Dllm{} // no Load, no worker: must fail fast, not hang
+			_, err := d.PredictRich(&pb.PredictOptions{Prompt: "p"})
+			Expect(err).To(HaveOccurred())
+		})
+
+		It("makes a concurrent Free wait for the in-flight request (both finish cleanly)", func() {
+			// server.go's Free has no locking of its own: the backend's genMu
+			// must hold Free back until the racing generate drains, instead of
+			// closing the jobs channel (panic) or freeing the C ctx under it.
+			fake := &fakeGen{out: "x", delay: 50 * time.Millisecond}
+			d := newTestDllm(fake, nil)
+
+			predictDone := make(chan error, 1)
+			go func() {
+				defer GinkgoRecover()
+				_, err := d.PredictRich(&pb.PredictOptions{Prompt: "p"})
+				predictDone <- err
+			}()
+			// Wait until the fake generate is actually in flight (the read
+			// lock is held from before submit until PredictRich returns).
+			Eventually(func() int {
+				_, maxInFlight := fake.snapshot()
+				return maxInFlight
+			}).Should(Equal(1))
+
+			Expect(d.Free()).To(Succeed())
+			// Free's write lock means the request finished before Free did.
+			var predictErr error
+			Eventually(predictDone).Should(Receive(&predictErr))
+			Expect(predictErr).ToNot(HaveOccurred())
+		})
+
+		It("returns model-not-loaded for requests after Free", func() {
+			fake := &fakeGen{out: "x"}
+			d := newTestDllm(fake, nil)
+			Expect(d.Free()).To(Succeed())
+
+			_, err := d.PredictRich(&pb.PredictOptions{Prompt: "p"})
+			Expect(err).To(MatchError(ContainSubstring("model not loaded")))
+		})
+
+		It("serializes concurrent requests through the worker goroutine", func() {
+			// dllm_capi.h: one ctx = one concurrent generate. Two overlapping
+			// PredictRich calls must execute the C calls one at a time.
+			fake := &fakeGen{out: "x", delay: 30 * time.Millisecond}
+			d := newTestDllm(fake, nil)
+
+			var wg sync.WaitGroup
+			for range 2 {
+				wg.Add(1)
+				go func() {
+					defer wg.Done()
+					defer GinkgoRecover()
+					_, err := d.PredictRich(&pb.PredictOptions{Prompt: "p"})
+					Expect(err).ToNot(HaveOccurred())
+				}()
+			}
+			wg.Wait()
+
+			calls, maxInFlight := fake.snapshot()
+			Expect(calls).To(HaveLen(2))
+			Expect(maxInFlight).To(Equal(1), "generate calls overlapped despite the worker queue")
+		})
+	})
+
+	Describe("PredictStreamRich", func() {
+		It("emits one reply per delta-producing block and leaves the channel open", func() {
+			// Blocks split mid-marker and mid-payload: the parser's holdback
+			// must keep marker fragments out of the emitted deltas.
+			fake := &fakeGen{blocks: []string{
+				"<|channel>thou",        // partial channel open: no deltas yet
+				"ght\nponder",           // header completes, reasoning starts
+				"ing<channel|>Hi ",      // reasoning ends, content starts
+				"there<turn|>discarded", // turn ends: trailing text dropped
+			}}
+			d := newTestDllm(fake, nil)
+
+			ch := make(chan *pb.Reply, 16)
+			err := d.PredictStreamRich(&pb.PredictOptions{
+				UseTokenizerTemplate: true,
+				Messages:             []*pb.Message{{Role: "user", Content: "hi"}},
+			}, ch)
+			Expect(err).ToNot(HaveOccurred())
+
+			replies := drainReplies(ch)
+			Expect(replies).To(HaveLen(3), "block 1 completes no delta and must not produce a reply")
+
+			var content, reasoning string
+			for _, r := range replies {
+				for _, delta := range r.GetChatDeltas() {
+					content += delta.GetContent()
+					reasoning += delta.GetReasoningContent()
+				}
+			}
+			Expect(reasoning).To(Equal("pondering"))
+			Expect(content).To(Equal("Hi there"))
+			// Message mirrors each reply's content so legacy consumers see
+			// exactly the displayed tokens.
+			Expect(string(replies[1].GetMessage())).To(Equal("Hi "))
+			Expect(string(replies[2].GetMessage())).To(Equal("there"))
+		})
+
+		It("streams raw blocks verbatim without use_tokenizer_template", func() {
+			fake := &fakeGen{blocks: []string{"abc", "", "<|channel>def"}}
+			d := newTestDllm(fake, nil)
+
+			ch := make(chan *pb.Reply, 16)
+			err := d.PredictStreamRich(&pb.PredictOptions{Prompt: "raw"}, ch)
+			Expect(err).ToNot(HaveOccurred())
+
+			replies := drainReplies(ch)
+			Expect(replies).To(HaveLen(2), "empty blocks produce no reply")
+			Expect(string(replies[0].GetMessage())).To(Equal("abc"))
+			Expect(string(replies[1].GetMessage())).To(Equal("<|channel>def"))
+			Expect(replies[1].GetChatDeltas()).To(HaveLen(1))
+		})
+
+		It("flushes parser holdback after the stream ends", func() {
+			// The unterminated partial marker "<chan" is held back during the
+			// stream and must come out as content on the final flush.
+			fake := &fakeGen{blocks: []string{"tail<chan"}}
+			d := newTestDllm(fake, nil)
+
+			ch := make(chan *pb.Reply, 16)
+			err := d.PredictStreamRich(&pb.PredictOptions{
+				UseTokenizerTemplate: true,
+				Messages:             []*pb.Message{{Role: "user", Content: "hi"}},
+			}, ch)
+			Expect(err).ToNot(HaveOccurred())
+
+			var content string
+			for _, r := range drainReplies(ch) {
+				content += string(r.GetMessage())
+			}
+			Expect(content).To(Equal("tail<chan"))
+		})
+
+		It("reassembles a multi-byte character split across block boundaries", func() {
+			// Per-block detokenize can split "€" (E2 82 AC) as E2 | 82 AC.
+			// Emitting the lone E2 would make grpc-go fail the marshal of the
+			// whole reply; the trailing incomplete sequence must be held back
+			// and completed by the next block.
+			fake := &fakeGen{blocks: []string{"caf\xe2", "\x82\xac ok"}}
+			d := newTestDllm(fake, nil)
+
+			ch := make(chan *pb.Reply, 16)
+			err := d.PredictStreamRich(&pb.PredictOptions{Prompt: "raw"}, ch)
+			Expect(err).ToNot(HaveOccurred())
+
+			var content string
+			for _, r := range drainReplies(ch) { // drain asserts ValidString per reply
+				content += string(r.GetMessage())
+			}
+			Expect(content).To(Equal("caf€ ok"))
+		})
+
+		It("reassembles a split multi-byte character in parsed (gemma4) mode too", func() {
+			fake := &fakeGen{blocks: []string{"caf\xe2", "\x82\xac<turn|>"}}
+			d := newTestDllm(fake, nil)
+
+			ch := make(chan *pb.Reply, 16)
+			err := d.PredictStreamRich(&pb.PredictOptions{
+				UseTokenizerTemplate: true,
+				Messages:             []*pb.Message{{Role: "user", Content: "hi"}},
+			}, ch)
+			Expect(err).ToNot(HaveOccurred())
+
+			var content string
+			for _, r := range drainReplies(ch) {
+				for _, delta := range r.GetChatDeltas() {
+					content += delta.GetContent()
+				}
+			}
+			Expect(content).To(Equal("caf€"))
+		})
+
+		It("replaces an incomplete sequence left at stream end with U+FFFD", func() {
+			// A byte-fallback token can leave a lone leading byte (0xE2) that
+			// no later block completes: the final flush must substitute it,
+			// never emit it raw and never drop into a marshal error.
+			fake := &fakeGen{blocks: []string{"ok\xe2"}}
+			d := newTestDllm(fake, nil)
+
+			ch := make(chan *pb.Reply, 16)
+			err := d.PredictStreamRich(&pb.PredictOptions{Prompt: "raw"}, ch)
+			Expect(err).ToNot(HaveOccurred())
+
+			var content string
+			for _, r := range drainReplies(ch) {
+				content += string(r.GetMessage())
+			}
+			Expect(content).To(Equal("ok<6F>"))
+		})
+
+		It("surfaces generator errors without sending replies", func() {
+			fake := &fakeGen{err: errors.New("stream boom")}
+			d := newTestDllm(fake, nil)
+
+			ch := make(chan *pb.Reply, 16)
+			err := d.PredictStreamRich(&pb.PredictOptions{Prompt: "p"}, ch)
+			Expect(err).To(MatchError("stream boom"))
+			Expect(drainReplies(ch)).To(BeEmpty())
+		})
+
+		It("errors before generating when no model is loaded", func() {
+			d := &Dllm{} // no Load, no worker: must fail fast, not hang
+			ch := make(chan *pb.Reply, 1)
+			err := d.PredictStreamRich(&pb.PredictOptions{Prompt: "p"}, ch)
+			Expect(err).To(MatchError(ContainSubstring("model not loaded")))
+			Expect(drainReplies(ch)).To(BeEmpty())
+		})
+	})
+
+	Describe("legacy Predict/PredictStream adapters", func() {
+		It("Predict returns the aggregated content string", func() {
+			fake := &fakeGen{out: "plain text"}
+			d := newTestDllm(fake, nil)
+
+			out, err := d.Predict(&pb.PredictOptions{Prompt: "p"})
+			Expect(err).ToNot(HaveOccurred())
+			Expect(out).To(Equal("plain text"))
+		})
+
+		It("PredictStream forwards content strings and closes the channel (legacy ownership)", func() {
+			fake := &fakeGen{blocks: []string{"a", "b"}}
+			d := newTestDllm(fake, nil)
+
+			ch := make(chan string, 16)
+			Expect(d.PredictStream(&pb.PredictOptions{Prompt: "p"}, ch)).To(Succeed())
+
+			var got []string
+			for s := range ch { // terminates only if the impl closed ch
+				got = append(got, s)
+			}
+			Expect(got).To(Equal([]string{"a", "b"}))
+		})
+	})
+
+	Describe("TokenizeString", func() {
+		It("decodes the C-side JSON id array", func() {
+			fake := &fakeGen{out: "[2,18]"}
+			d := newTestDllm(fake, nil)
+
+			resp, err := d.TokenizeString(&pb.PredictOptions{Prompt: "hello"})
+			Expect(err).ToNot(HaveOccurred())
+			Expect(resp.Length).To(Equal(int32(2)))
+			Expect(resp.Tokens).To(Equal([]int32{2, 18}))
+
+			calls, _ := fake.snapshot()
+			Expect(calls[0].prompt).To(Equal("hello"))
+		})
+
+		It("fails loud on a malformed id array", func() {
+			fake := &fakeGen{out: "not json"}
+			d := newTestDllm(fake, nil)
+
+			_, err := d.TokenizeString(&pb.PredictOptions{Prompt: "hello"})
+			Expect(err).To(HaveOccurred())
+		})
+
+		It("errors before tokenizing when no model is loaded", func() {
+			d := &Dllm{} // no Load, no worker: must fail fast, not hang
+			_, err := d.TokenizeString(&pb.PredictOptions{Prompt: "hello"})
+			Expect(err).To(MatchError(ContainSubstring("model not loaded")))
+		})
+	})
+
+	Describe("parseModelGenOpts", func() {
+		It("parses eb_*/blocks/kv_cache entries and types values by first successful parse", func() {
+			got := parseModelGenOpts([]string{
+				"eb_max_steps:16",
+				"eb_t_min:0.25",
+				"kv_cache:auto",
+				"blocks:4",
+				"unrelated_key:1", // other layers' options: skipped
+				"malformed",       // no colon: skipped
+			})
+			Expect(got).To(Equal(map[string]any{
+				"eb_max_steps": int64(16),
+				"eb_t_min":     0.25,
+				"kv_cache":     "auto",
+				"blocks":       int64(4),
+			}))
+		})
+
+		It("round-trips through buildOptsJSON (only flat scalars are produced)", func() {
+			got := parseModelGenOpts([]string{"eb_entropy_bound:0.8", "kv_cache:off"})
+			out, err := buildOptsJSON(got)
+			Expect(err).ToNot(HaveOccurred())
+			Expect(out).To(MatchJSON(`{"eb_entropy_bound":0.8,"kv_cache":"off"}`))
+		})
+	})
+})
+
+// ---------------------------------------------------------------------------
+// Gated backend round-trip against the real libdllm.so + tiny GGUF fixture.
+// ---------------------------------------------------------------------------
+
+var _ = Describe("Dllm backend (real tiny model)", func() {
+	BeforeEach(func() {
+		if os.Getenv("DLLM_TEST_LIBRARY") == "" || os.Getenv("DLLM_TEST_TINY_MODEL") == "" {
+			Skip("set DLLM_TEST_LIBRARY and DLLM_TEST_TINY_MODEL to run the backend round-trip")
+		}
+		ensureLibLoaded()
+		Expect(libLoadErr).ToNot(HaveOccurred())
+	})
+
+	It("round-trips Load, PredictRich, PredictStreamRich and TokenizeString", func() {
+		d := &Dllm{}
+		Expect(d.Load(&pb.ModelOptions{ModelFile: os.Getenv("DLLM_TEST_TINY_MODEL")})).To(Succeed())
+		DeferCleanup(func() { Expect(d.Free()).To(Succeed()) })
+
+		// TokenizeString: tiny fixture vocab tokenizes "hello" to [2,18].
+		resp, err := d.TokenizeString(&pb.PredictOptions{Prompt: "hello"})
+		Expect(err).ToNot(HaveOccurred())
+		Expect(resp.Tokens).To(Equal([]int32{2, 18}))
+		Expect(resp.Length).To(Equal(int32(2)))
+
+		req := &pb.PredictOptions{
+			UseTokenizerTemplate: true,
+			Messages:             []*pb.Message{{Role: "user", Content: "hello"}},
+			Tokens:               16,
+			Seed:                 7,
+		}
+
+		// Non-streaming: the tiny random-weight model emits arbitrary vocab
+		// words; with no gemma4 markers in them everything is content.
+		reply, err := d.PredictRich(req)
+		Expect(err).ToNot(HaveOccurred())
+		Expect(string(reply.GetMessage())).ToNot(BeEmpty())
+		Expect(reply.GetChatDeltas()).ToNot(BeEmpty())
+
+		// Streaming: at least one reply, and the channel-ownership rule is
+		// honored (drainReplies fails the spec on a closed channel).
+		ch := make(chan *pb.Reply, 64)
+		Expect(d.PredictStreamRich(req, ch)).To(Succeed())
+		replies := drainReplies(ch)
+		Expect(replies).ToNot(BeEmpty())
+		var streamed string
+		for _, r := range replies {
+			streamed += string(r.GetMessage())
+		}
+		Expect(streamed).ToNot(BeEmpty())
+	})
+
+	It("aborts an in-flight generation promptly on Cancel", func() {
+		d := &Dllm{}
+		// eb_max_steps inflates the per-block denoise loop so the full run
+		// takes ~10s on the tiny fixture (vs ~40ms at engine defaults; 16
+		// blocks, first block after ~0.7s) - long enough that a prompt
+		// post-cancel return is distinguishable from the generation simply
+		// finishing.
+		Expect(d.Load(&pb.ModelOptions{
+			ModelFile: os.Getenv("DLLM_TEST_TINY_MODEL"),
+			Options:   []string{"eb_max_steps:256"},
+		})).To(Succeed())
+		DeferCleanup(func() { Expect(d.Free()).To(Succeed()) })
+
+		ch := make(chan *pb.Reply, 64)
+		errCh := make(chan error, 1)
+		go func() {
+			defer GinkgoRecover()
+			errCh <- d.PredictStreamRich(&pb.PredictOptions{Prompt: "hello", Tokens: 256, Seed: 7}, ch)
+		}()
+
+		// Cancel only once the first block proves the generate is in
+		// flight: the C side resets the cancel flag on generate entry, so
+		// an earlier Cancel would be swallowed (dllm_capi.h race note).
+		Eventually(ch, "60s").Should(Receive())
+		cancelAt := time.Now()
+		d.Cancel()
+
+		// Uncancelled, ~10s of generation remain; the cancelled call must
+		// come back in milliseconds (the flag is checked per denoise step).
+		var genErr error
+		Eventually(errCh, "5s").Should(Receive(&genErr))
+		latency := time.Since(cancelAt)
+		Expect(genErr).To(MatchError(ContainSubstring("cancelled")))
+		GinkgoWriter.Printf("dllm cancel: PredictStreamRich returned %v after Cancel\n", latency)
+	})
+})

backend/go/dllm/gemma4_parser.go

@@ -0,0 +1,562 @@
+// Gemma4 (DiffusionGemma) streaming output parser: raw model text, fed in
+// arbitrary fragments (per committed diffusion block; a fragment can split
+// anywhere, including mid-marker and mid-payload), is turned into
+// pb.ChatDelta events (content / reasoning_content / tool_calls).
+//
+// Normative sources:
+//   - The chat template embedded at the top of gemma4_renderer.go ("tpl L<n>"
+//     citations below refer to its numbered lines). The OUTPUT format mirrors
+//     what the template renders for assistant history: thought channels
+//     (<|channel>thought\n ... <channel|>, tpl L240), tool calls
+//     (<|tool_call>call:name{...}<tool_call|>, tpl L246-L257) and turn ends
+//     (<turn|>, tpl L351).
+//   - vLLM PR #45163: vllm/tool_parsers/gemma4_tool_parser.py (marker
+//     handling, the call:name{...} argument grammar and its decoder, ported
+//     below) and vllm/reasoning/gemma4_reasoning_parser.py (channel markers,
+//     the "thought\n" role label, is_reasoning_end semantics).
+//
+// Initial state (derived from the generation prompt, tpl L356-L362, see
+// RenderGemma4):
+//   - enable_thinking=false: the prompt ends with "<|turn>model\n" +
+//     "<|channel>thought\n<channel|>" - an EMPTY thought channel, pre-opened
+//     AND pre-closed by the template. The model's output therefore starts in
+//     plain content. Use NewGemma4Parser(false).
+//   - enable_thinking=true: the prompt ends at "<|turn>model\n" and the model
+//     opens and closes its own thought channel in the OUTPUT
+//     ("<|channel>thought\n...reasoning...<channel|>final answer", per the
+//     vLLM Gemma4ReasoningParser docstring). The parser still starts in
+//     content state - the channel markers in the output drive the switch.
+//     Use NewGemma4Parser(false) here too.
+//   - NewGemma4Parser(true) is for callers that pre-open the thought channel
+//     in the prompt themselves (appending "<|channel>thought\n" after the
+//     generation prompt to force thinking): the output then begins mid-thought
+//     and everything is reasoning until the first <channel|>.
+//
+// State diagram (markers are consumed, never emitted):
+//
+//	             <|channel>                  \n (channel name dropped: the
+//	[content] --------------> [chan-header] ----> [thought]   "thought\n" role
+//	   ^ |  <channel|> (stray close: swallowed,                label, stripped
+//	   +-+  strip_thinking semantics, tpl L148-L158)           like vLLM does)
+//	   ^                  <channel|>
+//	   +----------------------------------------- [thought]
+//	   ^                  <tool_call|>                 | <|tool_call> (implicit
+//	   +-------------- [tool-call] <-------------------+  reasoning end, vLLM
+//	   |  <|tool_call>     ^                               is_reasoning_end)
+//	   +-------------------+
+//	[content]/[thought] --- <turn|> ---> [done]  (everything after is dropped)
+//
+// Buffering rules:
+//   - content/thought states hold back at most len(longest marker)-1 bytes:
+//     the longest tail that is still a proper prefix of a watched marker.
+//     Content is otherwise emitted immediately (no unbounded buffering).
+//   - the tool-call state buffers the whole payload until <tool_call|>. This
+//     is unbounded in principle but bounded in practice by the model's
+//     diffusion canvas, and is required because the call:name{...} payload
+//     only becomes decodable (and trustworthy) once complete - the same
+//     reason vLLM's parser accumulates before parsing.
+//   - Close() flushes whatever is still held: partial markers come out as
+//     content/reasoning (per the state that held them); an unterminated
+//     channel header or tool-call payload is re-emitted RAW (including its
+//     opening marker) as content - malformed output is never silently
+//     dropped (mirrors vLLM extract_tool_calls returning the raw text as
+//     content when its regex does not match).
+//
+// Streaming granularity DIVERGENCE from vLLM: vLLM re-parses the partial
+// payload on every token and streams argument-JSON diffs (its `partial=True`
+// decoder mode plus withholding logic exist only for that). Our fragments are
+// whole committed diffusion blocks, so each completed tool call is emitted
+// once, as a single ToolCallDelta carrying index + id + name + the full
+// arguments JSON - exactly the shape backend/python/vllm/backend.py emits
+// per call and pkg/functions.ToolCallsFromChatDeltas re-accumulates.
+package main
+
+import (
+	"encoding/json"
+	"regexp"
+	"strconv"
+	"strings"
+
+	pb "github.com/mudler/LocalAI/pkg/grpc/proto"
+)
+
+// gemma4CallRE is vLLM's tool_call_regex
+// (`<\|tool_call>call:([\w\-\.]+)\{(.*?)\}<tool_call\|>`, DOTALL) anchored to
+// a single already-extracted payload: name charset [\w\-.], braces mandatory.
+var gemma4CallRE = regexp.MustCompile(`(?s)^call:([\w\-.]+)\{(.*)\}$`)
+
+type g4State int
+
+const (
+	g4Content g4State = iota
+	g4ChanHeader
+	g4Thought
+	g4ToolCall
+	g4Done
+)
+
+// Markers watched per emitting state. A stray <tool_call|> outside a tool
+// call is deliberately NOT watched: it passes through verbatim, consistent
+// with the malformed-payload fallback re-emitting it as content.
+var (
+	gemma4ContentMarkers = []string{gemma4ChannelOpen, gemma4ChannelClose, gemma4ToolCallOpen, gemma4TurnEnd}
+	gemma4ThoughtMarkers = []string{gemma4ChannelClose, gemma4ToolCallOpen, gemma4TurnEnd}
+)
+
+type Gemma4Parser struct {
+	state g4State
+	// held is the per-state carry-over between Feed calls: a partial marker
+	// (content/thought), a partial channel header (chan-header) or the
+	// payload accumulated so far (tool-call).
+	held    string
+	toolIdx int
+}
+
+// NewGemma4Parser returns a parser positioned per the initial-state rules in
+// the header comment: startInThought=true only when the caller pre-opened a
+// thought channel in the prompt.
+func NewGemma4Parser(startInThought bool) *Gemma4Parser {
+	state := g4Content
+	if startInThought {
+		state = g4Thought
+	}
+	return &Gemma4Parser{state: state}
+}
+
+// Feed consumes the next output fragment and returns the deltas it completes.
+func (p *Gemma4Parser) Feed(text string) []*pb.ChatDelta {
+	if text == "" || p.state == g4Done {
+		return nil
+	}
+	pending := p.held + text
+	p.held = ""
+	var em g4Emitter
+	for pending != "" {
+		switch p.state {
+		case g4Content, g4Thought:
+			markers := gemma4ContentMarkers
+			if p.state == g4Thought {
+				markers = gemma4ThoughtMarkers
+			}
+			idx, marker := findEarliestGemma4Marker(pending, markers)
+			if idx == -1 {
+				hold := gemma4MarkerHoldback(pending, markers)
+				p.emitText(&em, pending[:len(pending)-hold])
+				p.held = pending[len(pending)-hold:]
+				pending = ""
+				continue
+			}
+			p.emitText(&em, pending[:idx])
+			pending = pending[idx+len(marker):]
+			switch marker {
+			case gemma4ChannelOpen:
+				p.state = g4ChanHeader
+			case gemma4ChannelClose:
+				// In thought: channel ends. In content: stray close,
+				// swallowed (strip_thinking keeps both sides, tpl L148-L158).
+				p.state = g4Content
+			case gemma4ToolCallOpen:
+				p.state = g4ToolCall
+			case gemma4TurnEnd:
+				p.state = g4Done
+			}
+		case g4ChanHeader:
+			// The channel header is "<name>\n"; the template only ever writes
+			// "thought" (tpl L240/L360) and the label is structural, so it is
+			// dropped, not emitted (vLLM strips the same "thought\n" prefix).
+			nl := strings.IndexByte(pending, '\n')
+			if nl == -1 {
+				p.held = pending
+				pending = ""
+				continue
+			}
+			pending = pending[nl+1:]
+			p.state = g4Thought
+		case g4ToolCall:
+			end := strings.Index(pending, gemma4ToolCallClose)
+			if end == -1 {
+				p.held = pending
+				pending = ""
+				continue
+			}
+			p.emitToolCall(&em, pending[:end])
+			pending = pending[end+len(gemma4ToolCallClose):]
+			p.state = g4Content
+		case g4Done:
+			pending = ""
+		}
+	}
+	return em.deltas
+}
+
+// Close flushes held-back partials. Incomplete structures (open channel
+// header, unterminated tool payload) are re-emitted raw as content rather
+// than dropped. The parser is finished afterwards.
+func (p *Gemma4Parser) Close() []*pb.ChatDelta {
+	var em g4Emitter
+	switch p.state {
+	case g4Content:
+		em.content(p.held)
+	case g4Thought:
+		em.reasoning(p.held)
+	case g4ChanHeader:
+		em.content(gemma4ChannelOpen + p.held)
+	case g4ToolCall:
+		em.content(gemma4ToolCallOpen + p.held)
+	case g4Done:
+	}
+	p.held = ""
+	p.state = g4Done
+	return em.deltas
+}
+
+func (p *Gemma4Parser) emitText(em *g4Emitter, s string) {
+	if p.state == g4Thought {
+		em.reasoning(s)
+		return
+	}
+	em.content(s)
+}
+
+// emitToolCall decodes one complete <|tool_call>...<tool_call|> payload. On a
+// payload that does not match call:name{...} the raw text (markers included)
+// is emitted as content, mirroring vLLM's extract_tool_calls fallback.
+func (p *Gemma4Parser) emitToolCall(em *g4Emitter, payload string) {
+	m := gemma4CallRE.FindStringSubmatch(payload)
+	if m == nil {
+		em.content(gemma4ToolCallOpen + payload + gemma4ToolCallClose)
+		return
+	}
+	// Index-based ids: deterministic (the split-invariance property relies
+	// on it) and matching the call_<n> convention of pkg/grpc/rich_test.go;
+	// core only needs ids to be non-empty and unique within the response.
+	em.tool(p.toolIdx, "call_"+strconv.Itoa(p.toolIdx), m[1], decodeGemma4Args(m[2], 0))
+	p.toolIdx++
+}
+
+// g4Emitter collects ChatDeltas; empty text events are dropped.
+type g4Emitter struct {
+	deltas []*pb.ChatDelta
+}
+
+func (e *g4Emitter) content(s string) {
+	if s != "" {
+		e.deltas = append(e.deltas, &pb.ChatDelta{Content: s})
+	}
+}
+
+func (e *g4Emitter) reasoning(s string) {
+	if s != "" {
+		e.deltas = append(e.deltas, &pb.ChatDelta{ReasoningContent: s})
+	}
+}
+
+func (e *g4Emitter) tool(index int, id, name, argsJSON string) {
+	e.deltas = append(e.deltas, &pb.ChatDelta{ToolCalls: []*pb.ToolCallDelta{{
+		Index:     int32(index),
+		Id:        id,
+		Name:      name,
+		Arguments: argsJSON,
+	}}})
+}
+
+// findEarliestGemma4Marker returns the position and value of the first
+// complete marker occurrence, or (-1, "").
+func findEarliestGemma4Marker(s string, markers []string) (int, string) {
+	best, bestMarker := -1, ""
+	for _, m := range markers {
+		if idx := strings.Index(s, m); idx >= 0 && (best == -1 || idx < best) {
+			best, bestMarker = idx, m
+		}
+	}
+	return best, bestMarker
+}
+
+// gemma4MarkerHoldback returns the length of the longest suffix of s that is
+// a proper prefix of a watched marker - the only bytes that may still grow
+// into a marker and therefore must not be emitted yet (bounded by the
+// longest marker, so content is never buffered unboundedly).
+func gemma4MarkerHoldback(s string, markers []string) int {
+	maxHold := 0
+	for _, m := range markers {
+		if len(m)-1 > maxHold {
+			maxHold = len(m) - 1
+		}
+	}
+	if len(s) < maxHold {
+		maxHold = len(s)
+	}
+	for k := maxHold; k >= 1; k-- {
+		tail := s[len(s)-k:]
+		for _, m := range markers {
+			if strings.HasPrefix(m, tail) {
+				return k
+			}
+		}
+	}
+	return 0
+}
+
+// ---------------------------------------------------------------------------
+// call:name{...} argument decoder
+//
+// Port of vLLM's _parse_gemma4_args / _parse_gemma4_array /
+// _parse_gemma4_value (gemma4_tool_parser.py) in non-partial mode only: this
+// parser decodes exclusively COMPLETE payloads (incomplete ones fall back to
+// raw content at Close), so vLLM's partial-withholding machinery
+// (trailing-dot floats, withheld bare tails) is intentionally not ported.
+//
+// Grammar (inverse of the renderer's formatGemma4Argument, tpl L118-L147):
+//
+//	args    := pair (',' pair)*
+//	pair    := key ':' value          (keys unquoted, up to the first ':')
+//	value   := string | object | array | bare
+//	string  := '<|"|>' ... '<|"|>'    (no escapes; unterminated -> rest)
+//	object  := '{' args '}'           (delimited strings skipped when
+//	array   := '[' value,* ']'         counting braces/brackets)
+//	bare    := true | false | null/none/nil | number | bare-string
+//
+// Output is a JSON object/array string with keys in payload order (Python
+// dict insertion order), built with HTML escaping off so payload text
+// survives byte-for-byte.
+// ---------------------------------------------------------------------------
+
+func isGemma4Space(c byte) bool { return c == ' ' || c == '\n' || c == '\t' }
+
+// gemma4MaxArgsDepth caps the mutual recursion between decodeGemma4Args and
+// decodeGemma4Array. Defense against model-generated deep nesting: a Go stack
+// overflow is a fatal process kill, not a recoverable error, so past the cap
+// a nested body gracefully degrades to a JSON string of its raw text.
+const gemma4MaxArgsDepth = 100
+
+// decodeGemma4Args decodes one args body (the text between the outer braces
+// of call:name{...}) into a JSON object string. depth is the current nesting
+// level (0 at the payload root); see gemma4MaxArgsDepth.
+func decodeGemma4Args(s string, depth int) string {
+	if depth > gemma4MaxArgsDepth {
+		return gemma4JSONString(s)
+	}
+	var b strings.Builder
+	b.WriteString("{")
+	first := true
+	pair := func(key, val string) {
+		if !first {
+			b.WriteString(",")
+		}
+		first = false
+		b.WriteString(gemma4JSONString(key))
+		b.WriteString(":")
+		b.WriteString(val)
+	}
+	i, n := 0, len(s)
+	for i < n {
+		for i < n && (isGemma4Space(s[i]) || s[i] == ',') {
+			i++
+		}
+		if i >= n {
+			break
+		}
+		keyStart := i
+		for i < n && s[i] != ':' {
+			i++
+		}
+		if i >= n {
+			break // no ':' -> trailing junk, dropped (vLLM does the same)
+		}
+		key := strings.TrimSpace(s[keyStart:i])
+		i++ // skip ':'
+		for i < n && isGemma4Space(s[i]) {
+			i++
+		}
+		if i >= n {
+			pair(key, `""`) // "key:" with nothing after -> empty string
+			break
+		}
+		switch {
+		case strings.HasPrefix(s[i:], gemma4StringDelim):
+			i += len(gemma4StringDelim)
+			if end := strings.Index(s[i:], gemma4StringDelim); end == -1 {
+				pair(key, gemma4JSONString(s[i:])) // unterminated -> take rest
+				i = n
+			} else {
+				pair(key, gemma4JSONString(s[i:i+end]))
+				i += end + len(gemma4StringDelim)
+			}
+		case s[i] == '{':
+			inner, next := scanGemma4Balanced(s, i, '{', '}')
+			pair(key, decodeGemma4Args(inner, depth+1))
+			i = next
+		case s[i] == '[':
+			inner, next := scanGemma4Balanced(s, i, '[', ']')
+			pair(key, decodeGemma4Array(inner, depth+1))
+			i = next
+		default:
+			valStart := i
+			for i < n && s[i] != ',' && s[i] != '}' && s[i] != ']' {
+				i++
+			}
+			if i == valStart {
+				// No progress (value starts on a stray '}'/']'): abort on
+				// malformed input rather than loop, like vLLM.
+				i = n
+				continue
+			}
+			pair(key, decodeGemma4Bare(s[valStart:i]))
+		}
+	}
+	b.WriteString("}")
+	return b.String()
+}
+
+// decodeGemma4Array decodes one array body (the text between '[' and ']')
+// into a JSON array string. depth is the current nesting level; see
+// gemma4MaxArgsDepth.
+func decodeGemma4Array(s string, depth int) string {
+	if depth > gemma4MaxArgsDepth {
+		return gemma4JSONString(s)
+	}
+	var b strings.Builder
+	b.WriteString("[")
+	first := true
+	item := func(val string) {
+		if !first {
+			b.WriteString(",")
+		}
+		first = false
+		b.WriteString(val)
+	}
+	i, n := 0, len(s)
+	for i < n {
+		for i < n && (isGemma4Space(s[i]) || s[i] == ',') {
+			i++
+		}
+		if i >= n {
+			break
+		}
+		switch {
+		case strings.HasPrefix(s[i:], gemma4StringDelim):
+			i += len(gemma4StringDelim)
+			if end := strings.Index(s[i:], gemma4StringDelim); end == -1 {
+				item(gemma4JSONString(s[i:]))
+				i = n
+			} else {
+				item(gemma4JSONString(s[i : i+end]))
+				i += end + len(gemma4StringDelim)
+			}
+		case s[i] == '{':
+			inner, next := scanGemma4Balanced(s, i, '{', '}')
+			item(decodeGemma4Args(inner, depth+1))
+			i = next
+		case s[i] == '[':
+			inner, next := scanGemma4Balanced(s, i, '[', ']')
+			item(decodeGemma4Array(inner, depth+1))
+			i = next
+		default:
+			valStart := i
+			for i < n && s[i] != ',' && s[i] != ']' {
+				i++
+			}
+			if i == valStart {
+				i = n // no progress: abort on malformed input, like vLLM
+				continue
+			}
+			item(decodeGemma4Bare(s[valStart:i]))
+		}
+	}
+	b.WriteString("]")
+	return b.String()
+}
+
+// scanGemma4Balanced scans a brace/bracket-balanced span starting at the
+// opener s[start], skipping over <|"|>-delimited strings so structural
+// characters inside them do not count (vLLM's depth scan). Returns the inner
+// text and the index just past the closer; an unterminated span yields the
+// rest of the string (the inner decoder still extracts what is there - this
+// path is only reachable from genuinely malformed complete payloads).
+func scanGemma4Balanced(s string, start int, open, close byte) (string, int) {
+	depth := 1
+	i := start + 1
+	innerStart := i
+	n := len(s)
+	for i < n && depth > 0 {
+		if strings.HasPrefix(s[i:], gemma4StringDelim) {
+			i += len(gemma4StringDelim)
+			if nd := strings.Index(s[i:], gemma4StringDelim); nd == -1 {
+				i = n
+			} else {
+				i += nd + len(gemma4StringDelim)
+			}
+			continue
+		}
+		switch s[i] {
+		case open:
+			depth++
+		case close:
+			depth--
+		}
+		i++
+	}
+	if depth > 0 {
+		return s[innerStart:], n
+	}
+	return s[innerStart : i-1], i
+}
+
+// decodeGemma4Bare maps an undelimited value to its JSON form: booleans,
+// null aliases (null/none/nil, case-insensitive - the renderer writes
+// Python None as "None", tpl L144-L145 via format_argument's else branch),
+// numbers (vLLM's rule: a '.' tries float, otherwise int; anything that
+// fails parses as a bare string).
+func decodeGemma4Bare(raw string) string {
+	v := strings.TrimSpace(raw)
+	if v == "" {
+		return `""`
+	}
+	if v == "true" || v == "false" {
+		return v
+	}
+	switch strings.ToLower(v) {
+	case "null", "none", "nil":
+		return "null"
+	}
+	if strings.Contains(v, ".") {
+		if f, err := strconv.ParseFloat(v, 64); err == nil {
+			return formatGemma4Float(f)
+		}
+	} else if iv, err := strconv.ParseInt(v, 10, 64); err == nil {
+		return strconv.FormatInt(iv, 10)
+	}
+	return gemma4JSONString(v)
+}
+
+// formatGemma4Float renders like Python's json.dumps(float): integral floats
+// keep a ".0" suffix ("108." decodes to 108.0, not 108), so the arguments
+// JSON matches what vLLM would have produced for the same payload.
+func formatGemma4Float(f float64) string {
+	s := strconv.FormatFloat(f, 'g', -1, 64)
+	if !strings.ContainsAny(s, ".eE") {
+		s += ".0"
+	}
+	return s
+}
+
+// gemma4JSONString encodes a JSON string WITHOUT HTML escaping (json.Marshal
+// would escape the angle brackets in "<div>" to \u003c / \u003e sequences;
+// payload text should survive
+// byte-for-byte, like Python's json.dumps(ensure_ascii=False)).
+func gemma4JSONString(s string) string {
+	var sb strings.Builder
+	enc := json.NewEncoder(&sb)
+	enc.SetEscapeHTML(false)
+	if err := enc.Encode(s); err != nil {
+		// Unreachable for plain strings; fall back to default escaping
+		// rather than emitting invalid JSON.
+		b, mErr := json.Marshal(s)
+		if mErr != nil {
+			return `""`
+		}
+		return string(b)
+	}
+	// Encode appends a trailing newline.
+	return strings.TrimSuffix(sb.String(), "\n")
+}

backend/go/dllm/gemma4_parser_test.go

@@ -0,0 +1,592 @@
+package main
+
+// Parser specs for Gemma4Parser (model output text -> pb.ChatDelta events).
+//
+// Fixture provenance:
+//   - Entries marked "vLLM: <name>" are direct ports of the named test from
+//     vLLM PR #45163, tests/tool_parsers/test_gemma4_tool_parser.py (the
+//     authoritative test-suite for the gemma4 tool-call wire format). The
+//     streaming tests' chunk lists are reused verbatim as Feed fragments.
+//   - Decoder entries port the TestParseGemma4Args / TestParseGemma4Array
+//     classes from the same file (non-partial mode only; this parser never
+//     decodes partial payloads, see the divergence note in gemma4_parser.go).
+//   - Channel/turn-marker expectations come from the chat template embedded
+//     in gemma4_renderer.go (tpl L356-L362 generation prompt, L148-L158
+//     strip_thinking) and vLLM's Gemma4ReasoningParser
+//     (vllm/reasoning/gemma4_reasoning_parser.py).
+
+import (
+	"encoding/json"
+	"fmt"
+	"strings"
+
+	. "github.com/onsi/ginkgo/v2"
+	. "github.com/onsi/gomega"
+
+	pb "github.com/mudler/LocalAI/pkg/grpc/proto"
+)
+
+// flatGemma4Tool is one accumulated tool call, mirroring how LocalAI core
+// folds ToolCallDelta streams (pkg/functions/chat_deltas.go
+// ToolCallsFromChatDeltas: name/id latch on first non-empty, arguments
+// concatenate per index). Tests flatten through the same rules so they
+// assert exactly what core will reconstruct.
+type flatGemma4Tool struct {
+	id   string
+	name string
+	args string
+}
+
+func flattenGemma4Deltas(deltas []*pb.ChatDelta) (string, string, []flatGemma4Tool) {
+	var content, reasoning strings.Builder
+	byIndex := map[int32]*flatGemma4Tool{}
+	maxIdx := int32(-1)
+	for _, d := range deltas {
+		content.WriteString(d.GetContent())
+		reasoning.WriteString(d.GetReasoningContent())
+		for _, tc := range d.GetToolCalls() {
+			acc, ok := byIndex[tc.GetIndex()]
+			if !ok {
+				acc = &flatGemma4Tool{}
+				byIndex[tc.GetIndex()] = acc
+			}
+			if tc.GetName() != "" {
+				acc.name = tc.GetName()
+			}
+			if tc.GetId() != "" {
+				acc.id = tc.GetId()
+			}
+			acc.args += tc.GetArguments()
+			if tc.GetIndex() > maxIdx {
+				maxIdx = tc.GetIndex()
+			}
+		}
+	}
+	var tools []flatGemma4Tool
+	for i := int32(0); i <= maxIdx; i++ {
+		if acc, ok := byIndex[i]; ok {
+			tools = append(tools, *acc)
+		}
+	}
+	return content.String(), reasoning.String(), tools
+}
+
+type wantGemma4Tool struct {
+	name     string
+	argsJSON string // compared with MatchJSON (key order irrelevant)
+}
+
+type parseGemma4Case struct {
+	startInThought bool
+	fragments      []string
+	wantContent    string
+	wantReasoning  string
+	wantTools      []wantGemma4Tool
+}
+
+func parseGemma4Fragments(startInThought bool, fragments []string) []*pb.ChatDelta {
+	p := NewGemma4Parser(startInThought)
+	var all []*pb.ChatDelta
+	for _, f := range fragments {
+		all = append(all, p.Feed(f)...)
+	}
+	return append(all, p.Close()...)
+}
+
+var _ = Describe("Gemma4Parser", func() {
+	DescribeTable("parses streamed gemma4 output into ChatDeltas",
+		func(c parseGemma4Case) {
+			content, reasoning, tools := flattenGemma4Deltas(parseGemma4Fragments(c.startInThought, c.fragments))
+			Expect(content).To(Equal(c.wantContent))
+			Expect(reasoning).To(Equal(c.wantReasoning))
+			Expect(tools).To(HaveLen(len(c.wantTools)))
+			seenIDs := map[string]bool{}
+			for i, want := range c.wantTools {
+				Expect(tools[i].name).To(Equal(want.name), "tool %d name", i)
+				Expect(tools[i].args).To(MatchJSON(want.argsJSON), "tool %d arguments", i)
+				Expect(tools[i].id).ToNot(BeEmpty(), "tool %d id", i)
+				Expect(seenIDs).ToNot(HaveKey(tools[i].id), "tool %d id must be unique", i)
+				seenIDs[tools[i].id] = true
+			}
+		},
+
+		// --- (1) pure content -------------------------------------------------
+		// vLLM: test_no_tool_calls
+		Entry("pure content, single fragment", parseGemma4Case{
+			fragments:   []string{"Hello, how can I help you today?"},
+			wantContent: "Hello, how can I help you today?",
+		}),
+
+		// --- (2) thought -> final transition ----------------------------------
+		// enable_thinking render: prompt ends at <|turn>model\n and the model
+		// opens/closes its own thought channel in the OUTPUT (vLLM
+		// Gemma4ReasoningParser docstring; tpl L356-L362). The "thought\n"
+		// role label after <|channel> is structural and must be stripped
+		// (vLLM _THOUGHT_PREFIX handling).
+		Entry("thought channel then final content", parseGemma4Case{
+			fragments:     []string{"<|channel>thought\nLet me think about this.\n<channel|>The answer is 42."},
+			wantReasoning: "Let me think about this.\n",
+			wantContent:   "The answer is 42.",
+		}),
+
+		// --- (3) startInThought both ways -------------------------------------
+		Entry("startInThought=true routes initial text to reasoning until <channel|>", parseGemma4Case{
+			startInThought: true,
+			fragments:      []string{"I am thinking hard.<channel|>Done."},
+			wantReasoning:  "I am thinking hard.",
+			wantContent:    "Done.",
+		}),
+		// A stray <channel|> with no open channel is swallowed, matching the
+		// template's strip_thinking (tpl L148-L158: the marker is dropped,
+		// text on both sides is kept).
+		Entry("startInThought=false keeps the same text as content, stray <channel|> swallowed", parseGemma4Case{
+			startInThought: false,
+			fragments:      []string{"I am thinking hard.<channel|>Done."},
+			wantContent:    "I am thinking hard.Done.",
+		}),
+
+		// --- (4) one tool call, full payload type zoo --------------------------
+		Entry("single tool call: strings, numbers, bools, null, nested object and array", parseGemma4Case{
+			fragments: []string{`<|tool_call>call:complex_function{text:<|"|>with, comma and {braces}<|"|>,count:42,score:3.14,yes:true,no:false,nothing:null,obj:{inner:<|"|>v<|"|>,k:1},arr:[<|"|>a<|"|>,2,true]}<tool_call|>`},
+			wantTools: []wantGemma4Tool{{
+				name:     "complex_function",
+				argsJSON: `{"text":"with, comma and {braces}","count":42,"score":3.14,"yes":true,"no":false,"nothing":null,"obj":{"inner":"v","k":1},"arr":["a",2,true]}`,
+			}},
+		}),
+
+		// --- (5) payload split across 3 fragments ------------------------------
+		Entry("tool-call payload split across three fragments", parseGemma4Case{
+			fragments: []string{
+				"<|tool_call>call:get_weather{loc",
+				`ation:<|"|>Paris, Fra`,
+				`nce<|"|>}<tool_call|>`,
+			},
+			wantTools: []wantGemma4Tool{{name: "get_weather", argsJSON: `{"location":"Paris, France"}`}},
+		}),
+
+		// --- (6) marker split across fragments ----------------------------------
+		Entry("tool-call open marker split across fragments", parseGemma4Case{
+			fragments: []string{
+				"<|tool_ca",
+				`ll>call:get_weather{location:<|"|>London<|"|>}<tool_call|>`,
+			},
+			wantTools: []wantGemma4Tool{{name: "get_weather", argsJSON: `{"location":"London"}`}},
+		}),
+		Entry("channel open marker split across fragments", parseGemma4Case{
+			fragments: []string{
+				"<|chan",
+				"nel>thought\ndeep thought<channel|>final",
+			},
+			wantReasoning: "deep thought",
+			wantContent:   "final",
+		}),
+
+		// --- (7) trailing partial marker held, flushed by Close -----------------
+		Entry("trailing partial marker is held back and flushed by Close", parseGemma4Case{
+			fragments:   []string{"Hello <|tool"},
+			wantContent: "Hello <|tool",
+		}),
+
+		// --- (8) malformed/incomplete payload -> content fallback ---------------
+		// vLLM: test_incomplete_tool_call (no end marker: the whole text stays
+		// content, never silently dropped).
+		Entry("incomplete tool payload at Close is emitted as raw content", parseGemma4Case{
+			fragments:   []string{`<|tool_call>call:get_weather{location:<|"|>London`},
+			wantContent: `<|tool_call>call:get_weather{location:<|"|>London`,
+		}),
+		Entry("malformed complete payload is emitted as raw content, parsing continues", parseGemma4Case{
+			fragments:   []string{"<|tool_call>oops no call syntax<tool_call|> done"},
+			wantContent: "<|tool_call>oops no call syntax<tool_call|> done",
+		}),
+
+		// --- (9) <turn|> ends the turn -------------------------------------------
+		Entry("text after <turn|> is ignored, including later fragments", parseGemma4Case{
+			fragments: []string{
+				"before<turn|>after",
+				`more <|tool_call>call:f{}<tool_call|>`,
+			},
+			wantContent: "before",
+		}),
+		Entry("<turn|> inside a thought channel ends the turn", parseGemma4Case{
+			startInThought: true,
+			fragments:      []string{"thinking<turn|>ignored"},
+			wantReasoning:  "thinking",
+		}),
+
+		// --- (10) ported vLLM non-streaming cases ---------------------------------
+		// vLLM: test_single_tool_call
+		Entry("vLLM: test_single_tool_call", parseGemma4Case{
+			fragments: []string{`<|tool_call>call:get_weather{location:<|"|>London<|"|>}<tool_call|>`},
+			wantTools: []wantGemma4Tool{{name: "get_weather", argsJSON: `{"location":"London"}`}},
+		}),
+		// vLLM: test_multiple_arguments
+		Entry("vLLM: test_multiple_arguments", parseGemma4Case{
+			fragments: []string{`<|tool_call>call:get_weather{location:<|"|>San Francisco<|"|>,unit:<|"|>celsius<|"|>}<tool_call|>`},
+			wantTools: []wantGemma4Tool{{name: "get_weather", argsJSON: `{"location":"San Francisco","unit":"celsius"}`}},
+		}),
+		// vLLM: test_text_before_tool_call. DIVERGENCE: vLLM's non-streaming
+		// extractor trims the content ("...you."); a streaming parser cannot
+		// retroactively trim already-emitted text, so the trailing space is
+		// kept (vLLM's own streaming path keeps it too, see
+		// test_streaming_text_before_tool_call which only checks a prefix).
+		Entry("vLLM: test_text_before_tool_call (streaming semantics: no trim)", parseGemma4Case{
+			fragments:   []string{`Let me check the weather for you. <|tool_call>call:get_weather{location:<|"|>Paris<|"|>}<tool_call|>`},
+			wantContent: "Let me check the weather for you. ",
+			wantTools:   []wantGemma4Tool{{name: "get_weather", argsJSON: `{"location":"Paris"}`}},
+		}),
+		// vLLM: test_multiple_tool_calls (also covers case 11: multi-tool sequence)
+		Entry("vLLM: test_multiple_tool_calls", parseGemma4Case{
+			fragments: []string{`<|tool_call>call:get_weather{location:<|"|>London<|"|>}<tool_call|><|tool_call>call:get_time{location:<|"|>London<|"|>}<tool_call|>`},
+			wantTools: []wantGemma4Tool{
+				{name: "get_weather", argsJSON: `{"location":"London"}`},
+				{name: "get_time", argsJSON: `{"location":"London"}`},
+			},
+		}),
+		// vLLM: test_nested_arguments
+		Entry("vLLM: test_nested_arguments", parseGemma4Case{
+			fragments: []string{`<|tool_call>call:complex_function{nested:{inner:<|"|>value<|"|>},list:[<|"|>a<|"|>,<|"|>b<|"|>]}<tool_call|>`},
+			wantTools: []wantGemma4Tool{{name: "complex_function", argsJSON: `{"nested":{"inner":"value"},"list":["a","b"]}`}},
+		}),
+		// vLLM: test_tool_call_with_number_and_boolean
+		Entry("vLLM: test_tool_call_with_number_and_boolean", parseGemma4Case{
+			fragments: []string{`<|tool_call>call:set_status{is_active:true,count:42,score:3.14}<tool_call|>`},
+			wantTools: []wantGemma4Tool{{name: "set_status", argsJSON: `{"is_active":true,"count":42,"score":3.14}`}},
+		}),
+		// vLLM: test_hyphenated_function_name
+		Entry("vLLM: test_hyphenated_function_name", parseGemma4Case{
+			fragments: []string{`<|tool_call>call:get-weather{location:<|"|>London<|"|>}<tool_call|>`},
+			wantTools: []wantGemma4Tool{{name: "get-weather", argsJSON: `{"location":"London"}`}},
+		}),
+		// vLLM: test_dotted_function_name
+		Entry("vLLM: test_dotted_function_name", parseGemma4Case{
+			fragments: []string{`<|tool_call>call:weather.get{location:<|"|>London<|"|>}<tool_call|>`},
+			wantTools: []wantGemma4Tool{{name: "weather.get", argsJSON: `{"location":"London"}`}},
+		}),
+		// vLLM: test_no_arguments
+		Entry("vLLM: test_no_arguments", parseGemma4Case{
+			fragments: []string{"<|tool_call>call:get_status{}<tool_call|>"},
+			wantTools: []wantGemma4Tool{{name: "get_status", argsJSON: `{}`}},
+		}),
+
+		// --- ported vLLM streaming cases (chunk lists reused as fragments) --------
+		// vLLM: test_basic_streaming_single_tool
+		Entry("vLLM: test_basic_streaming_single_tool", parseGemma4Case{
+			fragments: []string{
+				"<|tool_call>",
+				"call:get_weather{",
+				`location:<|"|>Paris`,
+				", France",
+				`<|"|>}`,
+				"<tool_call|>",
+			},
+			wantTools: []wantGemma4Tool{{name: "get_weather", argsJSON: `{"location":"Paris, France"}`}},
+		}),
+		// vLLM: test_streaming_multi_arg
+		Entry("vLLM: test_streaming_multi_arg", parseGemma4Case{
+			fragments: []string{
+				"<|tool_call>",
+				"call:get_weather{",
+				`location:<|"|>Tokyo<|"|>,`,
+				`unit:<|"|>celsius<|"|>}`,
+				"<tool_call|>",
+			},
+			wantTools: []wantGemma4Tool{{name: "get_weather", argsJSON: `{"location":"Tokyo","unit":"celsius"}`}},
+		}),
+		// vLLM: test_streaming_text_before_tool_call
+		Entry("vLLM: test_streaming_text_before_tool_call", parseGemma4Case{
+			fragments: []string{
+				"Let me check ",
+				"the weather. ",
+				"<|tool_call>",
+				"call:get_weather{",
+				`location:<|"|>London<|"|>}`,
+				"<tool_call|>",
+			},
+			wantContent: "Let me check the weather. ",
+			wantTools:   []wantGemma4Tool{{name: "get_weather", argsJSON: `{"location":"London"}`}},
+		}),
+		// vLLM: test_streaming_numeric_args
+		Entry("vLLM: test_streaming_numeric_args", parseGemma4Case{
+			fragments: []string{
+				"<|tool_call>",
+				"call:set_config{",
+				"count:42,",
+				"active:true}",
+				"<tool_call|>",
+			},
+			wantTools: []wantGemma4Tool{{name: "set_config", argsJSON: `{"count":42,"active":true}`}},
+		}),
+		// vLLM: test_streaming_boolean_split_across_chunks
+		Entry("vLLM: test_streaming_boolean_split_across_chunks", parseGemma4Case{
+			fragments: []string{
+				"<|tool_call>",
+				"call:search{input:{all:tru",
+				"e}}",
+				"<tool_call|>",
+			},
+			wantTools: []wantGemma4Tool{{name: "search", argsJSON: `{"input":{"all":true}}`}},
+		}),
+		// vLLM: test_streaming_false_split_across_chunks
+		Entry("vLLM: test_streaming_false_split_across_chunks", parseGemma4Case{
+			fragments: []string{
+				"<|tool_call>",
+				"call:set{flag:fals",
+				"e}",
+				"<tool_call|>",
+			},
+			wantTools: []wantGemma4Tool{{name: "set", argsJSON: `{"flag":false}`}},
+		}),
+		// vLLM: test_streaming_number_split_across_chunks
+		Entry("vLLM: test_streaming_number_split_across_chunks", parseGemma4Case{
+			fragments: []string{
+				"<|tool_call>",
+				"call:set{count:4",
+				"2}",
+				"<tool_call|>",
+			},
+			wantTools: []wantGemma4Tool{{name: "set", argsJSON: `{"count":42}`}},
+		}),
+		// vLLM: test_streaming_empty_args
+		Entry("vLLM: test_streaming_empty_args", parseGemma4Case{
+			fragments: []string{
+				"<|tool_call>",
+				"call:get_status{}",
+				"<tool_call|>",
+			},
+			wantTools: []wantGemma4Tool{{name: "get_status", argsJSON: `{}`}},
+		}),
+		// vLLM: test_streaming_split_delimiter_no_invalid_json (string
+		// delimiter <|"|> split across fragments must not leak fragments).
+		Entry("vLLM: test_streaming_split_delimiter_no_invalid_json", parseGemma4Case{
+			fragments: []string{
+				"<|tool_call>",
+				"call:todowrite{",
+				`content:<|"|>Buy milk<|`,
+				`"|>}`,
+				"<tool_call|>",
+			},
+			wantTools: []wantGemma4Tool{{name: "todowrite", argsJSON: `{"content":"Buy milk"}`}},
+		}),
+		// vLLM: test_streaming_does_not_duplicate_plain_text_after_tool_call
+		Entry("vLLM: test_streaming_does_not_duplicate_plain_text_after_tool_call", parseGemma4Case{
+			fragments: []string{
+				"<|tool_call>",
+				"call:get_weather{",
+				`location:<|"|>Paris<|"|>}`,
+				"<tool_call|><",
+				"div>",
+			},
+			wantContent: "<div>",
+			wantTools:   []wantGemma4Tool{{name: "get_weather", argsJSON: `{"location":"Paris"}`}},
+		}),
+		// vLLM: test_streaming_html_argument_does_not_duplicate_tag_prefixes
+		Entry("vLLM: test_streaming_html_argument_does_not_duplicate_tag_prefixes", parseGemma4Case{
+			fragments: []string{
+				"<|tool_call>",
+				"call:write_file{",
+				`path:<|"|>index.html<|"|>,`,
+				`content:<|"|><!DOCTYPE html>` + "\n<",
+				`html lang="zh-CN">` + "\n<",
+				"head>\n    <",
+				`meta charset="UTF-8">` + "\n    <",
+				`meta name="viewport" content="width=device-width">` + "\n",
+				`<|"|>}`,
+				"<tool_call|>",
+			},
+			wantTools: []wantGemma4Tool{{
+				name:     "write_file",
+				argsJSON: `{"path":"index.html","content":"<!DOCTYPE html>\n<html lang=\"zh-CN\">\n<head>\n    <meta charset=\"UTF-8\">\n    <meta name=\"viewport\" content=\"width=device-width\">\n"}`,
+			}},
+		}),
+		// vLLM: test_streaming_single_chunk_complete_tool_call
+		Entry("vLLM: test_streaming_single_chunk_complete_tool_call", parseGemma4Case{
+			fragments: []string{`<|tool_call>call:name_a_color{color_hex:<|"|>00ff11<|"|>}<tool_call|>`},
+			wantTools: []wantGemma4Tool{{name: "name_a_color", argsJSON: `{"color_hex":"00ff11"}`}},
+		}),
+		// vLLM: test_streaming_multi_chunk_batched_tool_calls (two complete
+		// calls in ONE fragment; both must come out with distinct indices)
+		Entry("vLLM: test_streaming_multi_chunk_batched_tool_calls", parseGemma4Case{
+			fragments: []string{
+				`<|tool_call>call:get_weather{location:<|"|>London<|"|>}<tool_call|>` +
+					`<|tool_call>call:get_time{timezone:<|"|>GMT<|"|>}<tool_call|>`,
+			},
+			wantTools: []wantGemma4Tool{
+				{name: "get_weather", argsJSON: `{"location":"London"}`},
+				{name: "get_time", argsJSON: `{"timezone":"GMT"}`},
+			},
+		}),
+		// vLLM: test_streaming_trailing_bare_bool_not_duplicated
+		Entry("vLLM: test_streaming_trailing_bare_bool_not_duplicated", parseGemma4Case{
+			fragments: []string{
+				"<|tool_call>",
+				"call:Edit{",
+				`file_path:<|"|>src/env.py<|"|>,`,
+				`old_string:<|"|>old_val<|"|>,`,
+				`new_string:<|"|>new_val<|"|>,`,
+				"replace_all:",
+				"false}",
+				"<tool_call|>",
+			},
+			wantTools: []wantGemma4Tool{{
+				name:     "Edit",
+				argsJSON: `{"file_path":"src/env.py","old_string":"old_val","new_string":"new_val","replace_all":false}`,
+			}},
+		}),
+
+		// --- implicit reasoning end on <|tool_call> (vLLM is_reasoning_end:
+		// a tool_call token means reasoning is over) -----------------------------
+		Entry("tool call inside an open thought channel ends the reasoning", parseGemma4Case{
+			startInThought: true,
+			fragments:      []string{`need the weather<|tool_call>call:get_weather{location:<|"|>Rome<|"|>}<tool_call|>`},
+			wantReasoning:  "need the weather",
+			wantTools:      []wantGemma4Tool{{name: "get_weather", argsJSON: `{"location":"Rome"}`}},
+		}),
+
+		// --- (12) empty fragments are no-ops --------------------------------------
+		Entry("empty fragments are no-ops", parseGemma4Case{
+			fragments:   []string{"", "Hello", "", "", " world", ""},
+			wantContent: "Hello world",
+		}),
+	)
+
+	It("returns no deltas for an empty fragment and after Close", func() {
+		p := NewGemma4Parser(false)
+		Expect(p.Feed("")).To(BeEmpty())
+		Expect(p.Feed("hi")).ToNot(BeEmpty())
+		Expect(p.Close()).To(BeEmpty()) // nothing held back
+		// The parser is finished after Close: further input is dropped.
+		Expect(p.Feed("more")).To(BeEmpty())
+		Expect(p.Close()).To(BeEmpty())
+	})
+
+	It("generates index-based tool call ids (call_<index>)", func() {
+		// Mirrors the index-based id convention of pkg/grpc/rich_test.go and
+		// keeps ids deterministic for the split-invariance property below.
+		deltas := parseGemma4Fragments(false, []string{
+			`<|tool_call>call:a{}<tool_call|><|tool_call>call:b{}<tool_call|>`,
+		})
+		_, _, tools := flattenGemma4Deltas(deltas)
+		Expect(tools).To(HaveLen(2))
+		Expect(tools[0].id).To(Equal("call_0"))
+		Expect(tools[1].id).To(Equal("call_1"))
+	})
+
+	// Property: for a fixed full output, EVERY 2-split position must yield
+	// exactly the same flattened result as the unsplit parse. This kills
+	// fragment-boundary bugs (mid-marker, mid-delimiter, mid-payload splits).
+	DescribeTable("2-split fragment invariance",
+		func(startInThought bool, full string) {
+			refContent, refReasoning, refTools := flattenGemma4Deltas(
+				parseGemma4Fragments(startInThought, []string{full}))
+			for i := 0; i <= len(full); i++ {
+				content, reasoning, tools := flattenGemma4Deltas(
+					parseGemma4Fragments(startInThought, []string{full[:i], full[i:]}))
+				Expect(content).To(Equal(refContent), fmt.Sprintf("content diverged at split %d", i))
+				Expect(reasoning).To(Equal(refReasoning), fmt.Sprintf("reasoning diverged at split %d", i))
+				Expect(tools).To(Equal(refTools), fmt.Sprintf("tool calls diverged at split %d", i))
+			}
+		},
+		Entry("thought + content + two tool calls + turn end", false,
+			"<|channel>thought\nPondering the request...\n<channel|>Sure - calling tools now. "+
+				`<|tool_call>call:get_weather{location:<|"|>Paris, France<|"|>,unit:<|"|>celsius<|"|>,days:3,detailed:true}<tool_call|>`+
+				`<|tool_call>call:get_time{timezone:<|"|>Europe/Lisbon<|"|>,nested:{flag:false,vals:[1,2.5,<|"|>x<|"|>]}}<tool_call|>`+
+				"Done.<turn|>ignored tail"),
+		Entry("startInThought + tool call + trailing partial marker", true,
+			`Deep thought<channel|>final answer <|tool_call>call:noop{}<tool_call|> trailing <|tool`),
+		Entry("malformed payload fallback", false,
+			`pre <|tool_call>not a call<tool_call|> post`),
+	)
+})
+
+// Decoder-level ports of vLLM's TestParseGemma4Args / TestParseGemma4Array
+// (non-partial mode; the partial-withholding tests do not apply because this
+// parser only ever decodes COMPLETE payloads, see gemma4_parser.go).
+var _ = Describe("decodeGemma4Args", func() {
+	DescribeTable("decodes the gemma4 call syntax into JSON arguments",
+		func(in, wantJSON string) {
+			Expect(decodeGemma4Args(in, 0)).To(MatchJSON(wantJSON))
+		},
+		// vLLM: test_empty_string / test_whitespace_only
+		Entry("empty string", "", `{}`),
+		Entry("whitespace only", "   ", `{}`),
+		// vLLM: test_single_string_value
+		Entry("single string value", `location:<|"|>Paris<|"|>`, `{"location":"Paris"}`),
+		// vLLM: test_string_value_with_comma
+		Entry("string value with comma", `location:<|"|>Paris, France<|"|>`, `{"location":"Paris, France"}`),
+		// vLLM: test_multiple_string_values
+		Entry("multiple string values", `location:<|"|>San Francisco<|"|>,unit:<|"|>celsius<|"|>`, `{"location":"San Francisco","unit":"celsius"}`),
+		// vLLM: test_integer_value / test_float_value
+		Entry("integer value", "count:42", `{"count":42}`),
+		Entry("float value", "score:3.14", `{"score":3.14}`),
+		// vLLM: test_boolean_true / test_boolean_false
+		Entry("boolean true", "flag:true", `{"flag":true}`),
+		Entry("boolean false", "flag:false", `{"flag":false}`),
+		// vLLM: test_null_value (bare null must become JSON null, not "null")
+		Entry("null value", "param:null", `{"param":null}`),
+		// vLLM: test_mixed_types
+		Entry("mixed types", `name:<|"|>test<|"|>,count:42,active:true,score:3.14`,
+			`{"name":"test","count":42,"active":true,"score":3.14}`),
+		// vLLM: test_nested_object
+		Entry("nested object", `nested:{inner:<|"|>value<|"|>}`, `{"nested":{"inner":"value"}}`),
+		// vLLM: test_array_of_strings
+		Entry("array of strings", `items:[<|"|>a<|"|>,<|"|>b<|"|>]`, `{"items":["a","b"]}`),
+		// vLLM: test_unterminated_string (take everything after the delimiter)
+		Entry("unterminated string", `key:<|"|>unterminated`, `{"key":"unterminated"}`),
+		// vLLM: test_empty_value (key with no value after colon)
+		Entry("empty value", "key:", `{"key":""}`),
+		// vLLM: test_trailing_dot_float_partial_withheld, non-partial branch
+		// (trailing-dot floats parse normally outside streaming).
+		Entry("trailing dot float, complete payload", "left:108.,right:22.8", `{"left":108.0,"right":22.8}`),
+	)
+
+	It("terminates and yields valid JSON on malformed input", func() {
+		// vLLM: test_malformed_partial_array (the assertion there is only
+		// "returns a dict without hanging"; ours is "valid JSON object").
+		out := decodeGemma4Args(":[t:[]", 0)
+		var v map[string]any
+		Expect(json.Unmarshal([]byte(out), &v)).To(Succeed())
+	})
+
+	It("degrades nesting beyond the recursion cap to a string value", func() {
+		// 200 levels of a:{a:{...a:1...}}. Without the depth cap the mutual
+		// recursion would grow the stack with the model's output; a Go stack
+		// overflow is a fatal process kill, so levels past gemma4MaxArgsDepth
+		// must gracefully fall back to the raw inner text as a JSON string.
+		const depth = 200
+		body := strings.Repeat("a:{", depth-1) + "a:1" + strings.Repeat("}", depth-1)
+		out := decodeGemma4Args(body, 0)
+		var v map[string]any
+		Expect(json.Unmarshal([]byte(out), &v)).To(Succeed())
+		levels := 0
+		var cur any = v
+		for {
+			m, ok := cur.(map[string]any)
+			if !ok {
+				break
+			}
+			Expect(m).To(HaveKey("a"))
+			cur = m["a"]
+			levels++
+		}
+		Expect(levels).To(Equal(gemma4MaxArgsDepth + 1))
+		Expect(cur).To(BeAssignableToTypeOf(""))
+		Expect(cur).To(ContainSubstring("a:{"))
+	})
+})
+
+var _ = Describe("decodeGemma4Array", func() {
+	DescribeTable("decodes gemma4 array bodies into JSON arrays",
+		func(in, wantJSON string) {
+			Expect(decodeGemma4Array(in, 0)).To(MatchJSON(wantJSON))
+		},
+		// vLLM: test_string_array / test_empty_array / test_bare_values
+		Entry("string array", `<|"|>a<|"|>,<|"|>b<|"|>`, `["a","b"]`),
+		Entry("empty array", "", `[]`),
+		Entry("bare values", "42,true,3.14", `[42,true,3.14]`),
+		// vLLM: test_string_element_with_closing_bracket (a ']' inside a
+		// delimited string must not close the array)
+		Entry("string element with closing bracket", `[<|"|>a]b<|"|>,<|"|>c<|"|>],<|"|>tail<|"|>`, `[["a]b","c"],"tail"]`),
+		// vLLM: test_stray_closing_bracket (no-progress abort, keep prefix)
+		Entry("stray closing bracket", "42,]trailing", `[42]`),
+	)
+})

backend/go/dllm/gemma4_renderer_test.go

@@ -0,0 +1,347 @@
+package main
+
+// Renderer specs for RenderGemma4 against the canonical gemma4 chat template
+// (see the normative template comment in gemma4_renderer.go).
+//
+// Fixture provenance:
+//   - "single user message" and "enable_thinking" are the EXACT expected
+//     decodes from transformers tests/models/diffusion_gemma/
+//     test_modeling_diffusion_gemma.py (test_diffusion_gemma_chat_template
+//     and ..._with_thinking) with ONE difference: the transformers fixtures
+//     start with "<bos>" because apply_chat_template tokenizes the rendered
+//     text with add_bos. Our prompt goes through dllm_capi_generate, whose
+//     run_generate already tokenizes with prepend_bos = vocab.add_bos
+//     (dllm.cpp src/capi.cpp:230-231, true for gemma4), so the renderer must
+//     NOT emit a literal <bos> (it would double) and every expected string
+//     here drops that leading token.
+//   - All other expected strings were produced by rendering the verbatim
+//     GGUF template with jinja2 3.1.2 (bos_token="<bos>") and dropping the
+//     leading "<bos>" for the same reason.
+
+import (
+	. "github.com/onsi/ginkgo/v2"
+	. "github.com/onsi/gomega"
+
+	pb "github.com/mudler/LocalAI/pkg/grpc/proto"
+)
+
+// Two-function tools array used by the tool fixtures (OpenAI wire shape, as
+// LocalAI passes it through PredictOptions.Tools).
+const testToolsJSON = `[{"type":"function","function":{"name":"get_weather","description":"Get the current weather in a location.","parameters":{"type":"object","properties":{"location":{"type":"string","description":"The city name."},"unit":{"type":"string","enum":["celsius","fahrenheit"]}},"required":["location"]}}},{"type":"function","function":{"name":"get_time","description":"Get the current time in a timezone.","parameters":{"type":"object","properties":{"timezone":{"type":"string","description":"IANA timezone name."}},"required":["timezone"]}}}]`
+
+// The <|tool>...<tool|> block the template renders for testToolsJSON inside
+// the system turn (jinja2-verified).
+const testToolsBlock = `<|tool>declaration:get_weather{description:<|"|>Get the current weather in a location.<|"|>,parameters:{properties:{location:{description:<|"|>The city name.<|"|>,type:<|"|>STRING<|"|>},unit:{enum:[<|"|>celsius<|"|>,<|"|>fahrenheit<|"|>],type:<|"|>STRING<|"|>}},required:[<|"|>location<|"|>],type:<|"|>OBJECT<|"|>}}<tool|><|tool>declaration:get_time{description:<|"|>Get the current time in a timezone.<|"|>,parameters:{properties:{timezone:{description:<|"|>IANA timezone name.<|"|>,type:<|"|>STRING<|"|>}},required:[<|"|>timezone<|"|>],type:<|"|>OBJECT<|"|>}}<tool|>`
+
+// A single tool exercising the deep format_parameters branches: array items
+// (string-typed and nested-array), nullable, enum+nullable, nested object
+// properties/required, and a response declaration.
+const complexToolsJSON = `[{"type":"function","function":{"name":"complex_tool","description":"A complex tool.","parameters":{"type":"object","properties":{"tags":{"type":"array","description":"Tags.","items":{"type":"string"}},"matrix":{"type":"array","items":{"type":"array","items":{"type":"number"}}},"opts":{"type":"object","description":"Options.","properties":{"depth":{"type":"integer","nullable":true}},"required":["depth"]},"mode":{"type":"string","enum":["a","b"],"nullable":true}},"required":["tags","opts"]},"response":{"description":"The result.","type":"object"}}}]`
+
+// jinja2-verified render of complexToolsJSON. Notable template quirks pinned
+// here: nested array items go through format_argument with ESCAPED keys and
+// an un-uppercased type (<|"|>type<|"|>:<|"|>number<|"|>), while direct item
+// types are uppercased; properties dictsort case-insensitively.
+const complexToolsBlock = `<|tool>declaration:complex_tool{description:<|"|>A complex tool.<|"|>,parameters:{properties:{matrix:{items:{items:{<|"|>type<|"|>:<|"|>number<|"|>},type:<|"|>ARRAY<|"|>},type:<|"|>ARRAY<|"|>},mode:{enum:[<|"|>a<|"|>,<|"|>b<|"|>],nullable:true,type:<|"|>STRING<|"|>},opts:{description:<|"|>Options.<|"|>,properties:{depth:{nullable:true,type:<|"|>INTEGER<|"|>}},required:[<|"|>depth<|"|>],type:<|"|>OBJECT<|"|>},tags:{description:<|"|>Tags.<|"|>,items:{type:<|"|>STRING<|"|>},type:<|"|>ARRAY<|"|>}},required:[<|"|>tags<|"|>,<|"|>opts<|"|>],type:<|"|>OBJECT<|"|>},response:{description:<|"|>The result.<|"|>,type:<|"|>OBJECT<|"|>}}<tool|>`
+
+type renderGemma4Case struct {
+	msgs               []*pb.Message
+	toolsJSON          string
+	enableThinking     bool
+	noGenerationPrompt bool // inverted so the zero value is the common case
+	expected           string
+}
+
+var _ = Describe("RenderGemma4", func() {
+	DescribeTable("renders the canonical gemma4 prompt",
+		func(c renderGemma4Case) {
+			out, err := RenderGemma4(c.msgs, c.toolsJSON, c.enableThinking, !c.noGenerationPrompt)
+			Expect(err).ToNot(HaveOccurred())
+			Expect(out).To(Equal(c.expected))
+			// The C-ABI generate prepends BOS itself: a literal <bos>
+			// anywhere in the rendered prompt would double-encode it.
+			Expect(out).ToNot(ContainSubstring("<bos>"))
+		},
+
+		// transformers fixture (test_diffusion_gemma_chat_template), sans <bos>:
+		// default thinking pre-opens an EMPTY thought channel in the
+		// generation prompt.
+		Entry("single user message, default (no thinking)", renderGemma4Case{
+			msgs: []*pb.Message{
+				{Role: "user", Content: "Write a long essay about Portugal."},
+			},
+			expected: "<|turn>user\nWrite a long essay about Portugal.<turn|>\n<|turn>model\n<|channel>thought\n<channel|>",
+		}),
+
+		// transformers fixture (test_diffusion_gemma_chat_template_with_thinking),
+		// sans <bos>: a system turn carrying <|think|> and NO auto-opened
+		// thought channel.
+		Entry("enable_thinking=true", renderGemma4Case{
+			msgs: []*pb.Message{
+				{Role: "user", Content: "Write a long essay about Portugal."},
+			},
+			enableThinking: true,
+			expected:       "<|turn>system\n<|think|>\n<turn|>\n<|turn>user\nWrite a long essay about Portugal.<turn|>\n<|turn>model\n",
+		}),
+
+		Entry("multi-turn user/assistant/user", renderGemma4Case{
+			msgs: []*pb.Message{
+				{Role: "user", Content: "Hello, who are you?"},
+				{Role: "assistant", Content: "I am Gemma, a helpful assistant."},
+				{Role: "user", Content: "Tell me a joke."},
+			},
+			expected: "<|turn>user\nHello, who are you?<turn|>\n<|turn>model\nI am Gemma, a helpful assistant.<turn|>\n<|turn>user\nTell me a joke.<turn|>\n<|turn>model\n<|channel>thought\n<channel|>",
+		}),
+
+		// tpl L178-L195: a leading system message is folded into the system
+		// turn (trimmed) and consumed from the loop.
+		Entry("system message folds into the system turn", renderGemma4Case{
+			msgs: []*pb.Message{
+				{Role: "system", Content: "You are a pirate."},
+				{Role: "user", Content: "Hello!"},
+			},
+			expected: "<|turn>system\nYou are a pirate.<turn|>\n<|turn>user\nHello!<turn|>\n<|turn>model\n<|channel>thought\n<channel|>",
+		}),
+
+		// tpl L182-L185: <|think|> goes at the very top of the SAME system
+		// turn, before the system prompt text.
+		Entry("system message with enable_thinking shares the turn", renderGemma4Case{
+			msgs: []*pb.Message{
+				{Role: "system", Content: "You are a pirate."},
+				{Role: "user", Content: "Hello!"},
+			},
+			enableThinking: true,
+			expected:       "<|turn>system\n<|think|>\nYou are a pirate.<turn|>\n<|turn>user\nHello!<turn|>\n<|turn>model\n",
+		}),
+
+		// tpl L196-L203: tool declarations render in the system turn, one
+		// <|tool>declaration:...<tool|> block per tool, no separators.
+		Entry("tools array (two functions)", renderGemma4Case{
+			msgs: []*pb.Message{
+				{Role: "user", Content: "What is the weather in Tokyo?"},
+			},
+			toolsJSON: testToolsJSON,
+			expected:  "<|turn>system\n" + testToolsBlock + "<turn|>\n<|turn>user\nWhat is the weather in Tokyo?<turn|>\n<|turn>model\n<|channel>thought\n<channel|>",
+		}),
+
+		// format_parameters deep branches (tpl L1-L85) + response declaration
+		// (tpl L106-L116).
+		Entry("complex tool schema (array items, nullable, nested object, response)", renderGemma4Case{
+			msgs: []*pb.Message{
+				{Role: "user", Content: "go"},
+			},
+			toolsJSON: complexToolsJSON,
+			expected:  "<|turn>system\n" + complexToolsBlock + "<turn|>\n<|turn>user\ngo<turn|>\n<|turn>model\n<|channel>thought\n<channel|>",
+		}),
+
+		// tpl L243-L313: assistant tool_calls render as
+		// <|tool_call>call:name{args}<tool_call|>; the following role=tool
+		// message renders inline as <|tool_response>response:name{value:..}
+		// <tool_response|>; the model turn stays OPEN (no <turn|>, no new
+		// generation prompt) so the model continues after the response.
+		Entry("assistant tool_calls + role=tool result", renderGemma4Case{
+			msgs: []*pb.Message{
+				{Role: "user", Content: "What is the weather in Tokyo?"},
+				{Role: "assistant", Content: "", ToolCalls: `[{"index":0,"id":"call_1","type":"function","function":{"name":"get_weather","arguments":"{\"location\":\"Tokyo\",\"unit\":\"celsius\"}"}}]`},
+				{Role: "tool", ToolCallId: "call_1", Content: "Sunny, 22 degrees celsius."},
+			},
+			toolsJSON: testToolsJSON,
+			expected:  "<|turn>system\n" + testToolsBlock + "<turn|>\n<|turn>user\nWhat is the weather in Tokyo?<turn|>\n<|turn>model\n" + `<|tool_call>call:get_weather{location:<|"|>Tokyo<|"|>,unit:<|"|>celsius<|"|>}<tool_call|><|tool_response>response:get_weather{value:<|"|>Sunny, 22 degrees celsius.<|"|>}<tool_response|>`,
+		}),
+
+		// tpl L348-L349: a tool_calls turn with no rendered responses ends
+		// on an OPEN <|tool_response> marker for the runtime to fill, and
+		// add_generation_prompt adds nothing (tpl L357).
+		Entry("assistant tool_calls without a result leaves <|tool_response> open", renderGemma4Case{
+			msgs: []*pb.Message{
+				{Role: "user", Content: "What is the weather in Tokyo?"},
+				{Role: "assistant", Content: "", ToolCalls: `[{"index":0,"id":"call_1","type":"function","function":{"name":"get_weather","arguments":"{\"location\":\"Tokyo\",\"unit\":\"celsius\"}"}}]`},
+			},
+			toolsJSON: testToolsJSON,
+			expected:  "<|turn>system\n" + testToolsBlock + "<turn|>\n<|turn>user\nWhat is the weather in Tokyo?<turn|>\n<|turn>model\n" + `<|tool_call>call:get_weather{location:<|"|>Tokyo<|"|>,unit:<|"|>celsius<|"|>}<tool_call|><|tool_response>`,
+		}),
+
+		// tpl L237-L241: reasoning_content renders as a thought channel only
+		// on a tool-calling turn after the last user message.
+		Entry("reasoning_content with tool_calls renders the thought channel", renderGemma4Case{
+			msgs: []*pb.Message{
+				{Role: "user", Content: "weather?"},
+				{Role: "assistant", Content: "", ReasoningContent: "I should call the tool", ToolCalls: `[{"index":0,"id":"c1","type":"function","function":{"name":"get_weather","arguments":"{\"location\":\"Tokyo\"}"}}]`},
+				{Role: "tool", ToolCallId: "c1", Content: "Sunny"},
+			},
+			expected: "<|turn>user\nweather?<turn|>\n<|turn>model\n<|channel>thought\nI should call the tool\n<channel|>" + `<|tool_call>call:get_weather{location:<|"|>Tokyo<|"|>}<tool_call|><|tool_response>response:get_weather{value:<|"|>Sunny<|"|>}<tool_response|>`,
+		}),
+
+		// tpl L220-L235: the assistant answer following its own tool round
+		// continues the SAME model turn (no second <|turn>model).
+		Entry("tool round then final assistant answer then user", renderGemma4Case{
+			msgs: []*pb.Message{
+				{Role: "user", Content: "weather?"},
+				{Role: "assistant", Content: "", ToolCalls: `[{"index":0,"id":"c1","type":"function","function":{"name":"get_weather","arguments":"{\"location\":\"Tokyo\"}"}}]`},
+				{Role: "tool", ToolCallId: "c1", Content: "Sunny"},
+				{Role: "assistant", Content: "It is sunny."},
+				{Role: "user", Content: "thanks"},
+			},
+			expected: "<|turn>user\nweather?<turn|>\n<|turn>model\n" + `<|tool_call>call:get_weather{location:<|"|>Tokyo<|"|>}<tool_call|><|tool_response>response:get_weather{value:<|"|>Sunny<|"|>}<tool_response|>` + "It is sunny.<turn|>\n<|turn>user\nthanks<turn|>\n<|turn>model\n<|channel>thought\n<channel|>",
+		}),
+
+		// format_argument (tpl L118-L147): numbers keep their JSON literal,
+		// booleans lower-case, nested maps have unquoted dictsorted keys,
+		// arrays bracketed; top-level args are dictsorted case-insensitively.
+		Entry("tool_call argument types (number/bool/nested/array)", renderGemma4Case{
+			msgs: []*pb.Message{
+				{Role: "user", Content: "go"},
+				{Role: "assistant", Content: "", ToolCalls: `[{"index":0,"id":"c1","type":"function","function":{"name":"f","arguments":"{\"count\":42,\"ratio\":3.5,\"flag\":true,\"off\":false,\"nested\":{\"x\":\"y\",\"n\":7},\"list\":[\"a\",1,true]}"}}]`},
+			},
+			expected: "<|turn>user\ngo<turn|>\n<|turn>model\n" + `<|tool_call>call:f{count:42,flag:true,list:[<|"|>a<|"|>,1,true],nested:{n:7,x:<|"|>y<|"|>},off:false,ratio:3.5}<tool_call|><|tool_response>`,
+		}),
+
+		// jinja dictsort is case-insensitive: alpha sorts before Beta.
+		Entry("tool_call argument dictsort is case-insensitive", renderGemma4Case{
+			msgs: []*pb.Message{
+				{Role: "user", Content: "go"},
+				{Role: "assistant", Content: "", ToolCalls: `[{"index":0,"id":"c1","type":"function","function":{"name":"f","arguments":"{\"Beta\":1,\"alpha\":2}"}}]`},
+			},
+			expected: "<|turn>user\ngo<turn|>\n<|turn>model\n<|tool_call>call:f{alpha:2,Beta:1}<tool_call|><|tool_response>",
+		}),
+
+		// jinja renders Python None as "None" (round-trips through vLLM's
+		// parser, which lowers "none" back to null).
+		Entry("tool_call null argument renders as None", renderGemma4Case{
+			msgs: []*pb.Message{
+				{Role: "user", Content: "go"},
+				{Role: "assistant", Content: "", ToolCalls: `[{"index":0,"id":"c1","type":"function","function":{"name":"f","arguments":"{\"maybe\":null}"}}]`},
+			},
+			expected: "<|turn>user\ngo<turn|>\n<|turn>model\n<|tool_call>call:f{maybe:None}<tool_call|><|tool_response>",
+		}),
+
+		Entry("tool_call empty arguments render empty braces", renderGemma4Case{
+			msgs: []*pb.Message{
+				{Role: "user", Content: "go"},
+				{Role: "assistant", Content: "", ToolCalls: `[{"index":0,"id":"c1","type":"function","function":{"name":"f","arguments":"{}"}}]`},
+			},
+			expected: "<|turn>user\ngo<turn|>\n<|turn>model\n<|tool_call>call:f{}<tool_call|><|tool_response>",
+		}),
+
+		// tpl L253-L254: a non-object arguments string renders verbatim.
+		Entry("tool_call non-object string arguments render verbatim", renderGemma4Case{
+			msgs: []*pb.Message{
+				{Role: "user", Content: "go"},
+				{Role: "assistant", Content: "", ToolCalls: `[{"index":0,"id":"c1","type":"function","function":{"name":"f","arguments":"just text"}}]`},
+			},
+			expected: "<|turn>user\ngo<turn|>\n<|turn>model\n<|tool_call>call:f{just text}<tool_call|><|tool_response>",
+		}),
+
+		// tpl L278-L285: unmatched tool_call_id falls back to the tool
+		// message's own name.
+		Entry("tool result name falls back when tool_call_id does not match", renderGemma4Case{
+			msgs: []*pb.Message{
+				{Role: "user", Content: "go"},
+				{Role: "assistant", Content: "", ToolCalls: `[{"index":0,"id":"c1","type":"function","function":{"name":"f","arguments":"{}"}}]`},
+				{Role: "tool", ToolCallId: "OTHER", Name: "named_tool", Content: "out"},
+			},
+			expected: "<|turn>user\ngo<turn|>\n<|turn>model\n" + `<|tool_call>call:f{}<tool_call|><|tool_response>response:named_tool{value:<|"|>out<|"|>}<tool_response|>`,
+		}),
+
+		// strip_thinking (tpl L148-L158): historical assistant content loses
+		// its <|channel>...<channel|> spans.
+		Entry("assistant content thinking channels are stripped", renderGemma4Case{
+			msgs: []*pb.Message{
+				{Role: "user", Content: "hi"},
+				{Role: "assistant", Content: "<|channel>thought\nsecret\n<channel|>visible answer"},
+				{Role: "user", Content: "more"},
+			},
+			expected: "<|turn>user\nhi<turn|>\n<|turn>model\nvisible answer<turn|>\n<|turn>user\nmore<turn|>\n<|turn>model\n<|channel>thought\n<channel|>",
+		}),
+
+		// tpl L220-L235: consecutive assistant messages suppress the second
+		// <|turn>model (continuation), but each still closes with <turn|>.
+		Entry("consecutive assistant messages continue the model turn", renderGemma4Case{
+			msgs: []*pb.Message{
+				{Role: "user", Content: "hi"},
+				{Role: "assistant", Content: "part one"},
+				{Role: "assistant", Content: "part two"},
+				{Role: "user", Content: "ok"},
+			},
+			expected: "<|turn>user\nhi<turn|>\n<|turn>model\npart one<turn|>\npart two<turn|>\n<|turn>user\nok<turn|>\n<|turn>model\n<|channel>thought\n<channel|>",
+		}),
+
+		Entry("add_generation_prompt=false renders no model turn", renderGemma4Case{
+			msgs: []*pb.Message{
+				{Role: "user", Content: "hi"},
+			},
+			noGenerationPrompt: true,
+			expected:           "<|turn>user\nhi<turn|>\n",
+		}),
+	)
+
+	Describe("error handling", func() {
+		It("fails loud on an unknown role", func() {
+			_, err := RenderGemma4([]*pb.Message{
+				{Role: "narrator", Content: "Meanwhile..."},
+			}, "", false, true)
+			Expect(err).To(HaveOccurred())
+			Expect(err.Error()).To(ContainSubstring(`unknown role "narrator"`))
+		})
+
+		It("fails on invalid tools JSON", func() {
+			_, err := RenderGemma4([]*pb.Message{
+				{Role: "user", Content: "hi"},
+			}, "{not json", false, true)
+			Expect(err).To(HaveOccurred())
+			Expect(err.Error()).To(ContainSubstring("tools JSON"))
+		})
+
+		It("fails on invalid tool_calls JSON", func() {
+			_, err := RenderGemma4([]*pb.Message{
+				{Role: "user", Content: "hi"},
+				{Role: "assistant", Content: "", ToolCalls: "{not json"},
+			}, "", false, true)
+			Expect(err).To(HaveOccurred())
+			Expect(err.Error()).To(ContainSubstring("tool_calls JSON"))
+		})
+
+		It("fails on an orphan tool message, naming its index", func() {
+			// A role:tool message with no preceding assistant tool_calls turn
+			// would be silently dropped by the jinja; we fail loud instead.
+			_, err := RenderGemma4([]*pb.Message{
+				{Role: "user", Content: "hi"},
+				{Role: "tool", Content: `{"temp": 20}`, ToolCallId: "call_1"},
+			}, "", false, true)
+			Expect(err).To(HaveOccurred())
+			Expect(err.Error()).To(ContainSubstring("orphan tool message 1"))
+		})
+
+		It("fails on trailing garbage after the tools JSON array", func() {
+			_, err := RenderGemma4([]*pb.Message{
+				{Role: "user", Content: "hi"},
+			}, "[] junk", false, true)
+			Expect(err).To(HaveOccurred())
+			Expect(err.Error()).To(ContainSubstring("tools JSON"))
+		})
+
+		It("fails when the tools JSON is not an array", func() {
+			_, err := RenderGemma4([]*pb.Message{
+				{Role: "user", Content: "hi"},
+			}, `{"type":"function"}`, false, true)
+			Expect(err).To(HaveOccurred())
+			Expect(err.Error()).To(ContainSubstring("tools JSON is not an array"))
+		})
+
+		It("fails when a tools array element is not an object", func() {
+			_, err := RenderGemma4([]*pb.Message{
+				{Role: "user", Content: "hi"},
+			}, `[42]`, false, true)
+			Expect(err).To(HaveOccurred())
+			Expect(err.Error()).To(ContainSubstring("tools[0] is not an object"))
+		})
+
+		It("rejects a nil message via the unknown-role check", func() {
+			// Pins current behavior: pb getters are nil-safe, so a nil message
+			// reads as role "" and trips the fail-loud unknown-role guard.
+			_, err := RenderGemma4([]*pb.Message{nil}, "", false, true)
+			Expect(err).To(HaveOccurred())
+			Expect(err.Error()).To(ContainSubstring(`unknown role "" in message 0`))
+		})
+	})
+})

backend/go/dllm/main.go

@@ -0,0 +1,85 @@
+package main
+
+// Started internally by LocalAI - one gRPC server per loaded model.
+//
+// Loads libdllm.so via purego and registers the 9-symbol flat C-ABI
+// declared in dllm.cpp's include/dllm_capi.h (ABI v1). The library name can
+// be overridden with DLLM_LIBRARY (mirrors the PARAKEET_LIBRARY /
+// WHISPER_LIBRARY convention in the sibling backends); the default looks
+// for the .so next to this binary (run.sh puts the package dir on
+// LD_LIBRARY_PATH).
+import (
+	"flag"
+	"fmt"
+	"os"
+
+	"github.com/ebitengine/purego"
+	grpc "github.com/mudler/LocalAI/pkg/grpc"
+)
+
+var (
+	addr = flag.String("addr", "localhost:50051", "the address to connect to")
+)
+
+type LibFuncs struct {
+	FuncPtr any
+	Name    string
+}
+
+// loadCAPI dlopens libName and binds the 9 dllm_capi_* entry points 1:1 to
+// dllm_capi.h, so an `nm libdllm.so | grep dllm_capi` is enough to spot
+// drift. Shared with the test suite (ensureLibLoaded), which drives the
+// bridge without the gRPC server.
+//
+// The C-ABI returns malloc'd char* buffers from tokenize_json/generate; we
+// register those as uintptr so we get the raw pointer back and can call
+// dllm_capi_free_string on it (purego's string return would copy and forget
+// the original pointer, leaking it on every call). last_error returns a
+// BORROWED pointer instead, so it is registered as a plain string: purego
+// copies it and nothing must be freed.
+func loadCAPI(libName string) error {
+	lib, err := purego.Dlopen(libName, purego.RTLD_NOW|purego.RTLD_GLOBAL)
+	if err != nil {
+		return fmt.Errorf("dllm: dlopen %q: %w", libName, err)
+	}
+
+	libFuncs := []LibFuncs{
+		{&cppAbiVersion, "dllm_capi_abi_version"},
+		{&cppLoad, "dllm_capi_load"},
+		{&cppFree, "dllm_capi_free"},
+		{&cppLastError, "dllm_capi_last_error"},
+		{&cppFreeString, "dllm_capi_free_string"},
+		{&cppTokenizeJSON, "dllm_capi_tokenize_json"},
+		{&cppGenerate, "dllm_capi_generate"},
+		{&cppGenerateStream, "dllm_capi_generate_stream"},
+		{&cppCancel, "dllm_capi_cancel"},
+	}
+	for _, lf := range libFuncs {
+		purego.RegisterLibFunc(lf.FuncPtr, lib, lf.Name)
+	}
+	return nil
+}
+
+func main() {
+	libName := os.Getenv("DLLM_LIBRARY")
+	if libName == "" {
+		libName = "libdllm.so"
+	}
+
+	if err := loadCAPI(libName); err != nil {
+		panic(err)
+	}
+
+	// Hard-fail on an ABI mismatch: the flat-pointer bindings above would
+	// otherwise misbehave silently against a future libdllm.so.
+	if v := cAbiVersion(); v != dllmABIVersion {
+		panic(fmt.Errorf("dllm: libdllm.so ABI=%d, this backend speaks ABI=%d", v, dllmABIVersion))
+	}
+	fmt.Fprintf(os.Stderr, "[dllm] ABI=%d\n", cAbiVersion())
+
+	flag.Parse()
+
+	if err := grpc.StartServer(*addr, &Dllm{}); err != nil {
+		panic(err)
+	}
+}

backend/go/dllm/package.sh

@@ -0,0 +1,24 @@
+#!/bin/bash
+#
+# T1 packaging stub: copy the binary, run.sh and libdllm.so into package/.
+# The full ldd walk (libc, libstdc++, libgomp, GPU runtimes, arch
+# detection) lands with the registration task, mirroring
+# backend/go/whisper/package.sh.
+
+set -e
+
+CURDIR=$(dirname "$(realpath "$0")")
+
+mkdir -p "$CURDIR/package/lib"
+
+cp -avf "$CURDIR/dllm-grpc" "$CURDIR/package/"
+cp -avf "$CURDIR/run.sh" "$CURDIR/package/"
+
+# libdllm.so + any soname symlinks, should upstream ever add them.
+cp -avf "$CURDIR"/libdllm.so* "$CURDIR/package/lib/" 2>/dev/null || {
+	echo "ERROR: libdllm.so not found in $CURDIR, run 'make' first" >&2
+	exit 1
+}
+
+echo "T1 package layout (full ldd walk lands with registration):"
+ls -liah "$CURDIR/package/" "$CURDIR/package/lib/"

backend/go/dllm/run.sh

@@ -0,0 +1,16 @@
+#!/bin/bash
+set -e
+
+CURDIR=$(dirname "$(realpath "$0")")
+
+export LD_LIBRARY_PATH="$CURDIR/lib:$CURDIR:${LD_LIBRARY_PATH:-}"
+
+# If a self-contained ld.so was packaged, route through it so the
+# packaged libc / libstdc++ are used instead of the host's (matches the
+# whisper / parakeet-cpp backends' runtime layout).
+if [ -f "$CURDIR/lib/ld.so" ]; then
+	echo "Using lib/ld.so"
+	exec "$CURDIR/lib/ld.so" "$CURDIR/dllm-grpc" "$@"
+fi
+
+exec "$CURDIR/dllm-grpc" "$@"

backend/index.yaml

@@ -95,6 +95,29 @@
     nvidia-l4t-cuda-13: "cuda13-nvidia-l4t-arm64-ds4"
     metal: "metal-ds4"
     metal-darwin-arm64: "metal-ds4"
+- &dllm
+  name: "dllm"
+  alias: "dllm"
+  license: mit
+  description: |
+    mudler/dllm.cpp - DiffusionGemma block-diffusion LLM inference engine
+    (C++/ggml, GGUF weights). Decodes whole token canvases per diffusion
+    round instead of autoregressive sampling. Runs on CPU and NVIDIA CUDA 13
+    (including Jetson/GB10 L4T targets).
+  urls:
+    - https://github.com/mudler/dllm.cpp
+  tags:
+    - text-to-text
+    - LLM
+    - gguf
+    - diffusion
+    - CPU
+    - CUDA
+  capabilities:
+    default: "cpu-dllm"
+    nvidia: "cuda13-dllm"
+    nvidia-cuda-13: "cuda13-dllm"
+    nvidia-l4t-cuda-13: "cuda13-nvidia-l4t-arm64-dllm"
 - &whispercpp
   name: "whisper"
   alias: "whisper"
@@ -1272,6 +1295,13 @@
     nvidia-l4t-cuda-13: "cuda13-nvidia-l4t-arm64-ds4-development"
     metal: "metal-ds4-development"
     metal-darwin-arm64: "metal-ds4-development"
+- !!merge <<: *dllm
+  name: "dllm-development"
+  capabilities:
+    default: "cpu-dllm-development"
+    nvidia: "cuda13-dllm-development"
+    nvidia-cuda-13: "cuda13-dllm-development"
+    nvidia-l4t-cuda-13: "cuda13-nvidia-l4t-arm64-dllm-development"
 - !!merge <<: *stablediffusionggml
   name: "stablediffusion-ggml-development"
   capabilities:
@@ -1859,6 +1889,37 @@
   uri: "quay.io/go-skynet/local-ai-backends:master-metal-darwin-arm64-ds4"
   mirrors:
     - localai/localai-backends:master-metal-darwin-arm64-ds4
+## dllm
+- !!merge <<: *dllm
+  name: "cpu-dllm"
+  uri: "quay.io/go-skynet/local-ai-backends:latest-cpu-dllm"
+  mirrors:
+    - localai/localai-backends:latest-cpu-dllm
+- !!merge <<: *dllm
+  name: "cpu-dllm-development"
+  uri: "quay.io/go-skynet/local-ai-backends:master-cpu-dllm"
+  mirrors:
+    - localai/localai-backends:master-cpu-dllm
+- !!merge <<: *dllm
+  name: "cuda13-dllm"
+  uri: "quay.io/go-skynet/local-ai-backends:latest-gpu-nvidia-cuda-13-dllm"
+  mirrors:
+    - localai/localai-backends:latest-gpu-nvidia-cuda-13-dllm
+- !!merge <<: *dllm
+  name: "cuda13-dllm-development"
+  uri: "quay.io/go-skynet/local-ai-backends:master-gpu-nvidia-cuda-13-dllm"
+  mirrors:
+    - localai/localai-backends:master-gpu-nvidia-cuda-13-dllm
+- !!merge <<: *dllm
+  name: "cuda13-nvidia-l4t-arm64-dllm"
+  uri: "quay.io/go-skynet/local-ai-backends:latest-nvidia-l4t-cuda-13-arm64-dllm"
+  mirrors:
+    - localai/localai-backends:latest-nvidia-l4t-cuda-13-arm64-dllm
+- !!merge <<: *dllm
+  name: "cuda13-nvidia-l4t-arm64-dllm-development"
+  uri: "quay.io/go-skynet/local-ai-backends:master-nvidia-l4t-cuda-13-arm64-dllm"
+  mirrors:
+    - localai/localai-backends:master-nvidia-l4t-cuda-13-arm64-dllm
 ## whisper
 - !!merge <<: *whispercpp
   name: "whisper-development"

core/http/app_test.go

@@ -383,13 +383,13 @@ var _ = Describe("API test", func() {
 			Expect(err).ToNot(HaveOccurred())
 
 			go func() {
-				if err := app.Start("127.0.0.1:9090"); err != nil && err != http.ErrServerClosed {
+				if err := app.Start(testHTTPAddr); err != nil && err != http.ErrServerClosed {
 					xlog.Error("server error", "error", err)
 				}
 			}()
 
 			defaultConfig := openai.DefaultConfig(apiKey)
-			defaultConfig.BaseURL = "http://127.0.0.1:9090/v1"
+			defaultConfig.BaseURL = testHTTPBase + "/v1"
 
 			client2 = openaigo.NewClient("")
 			client2.BaseURL = defaultConfig.BaseURL
@@ -418,7 +418,7 @@ var _ = Describe("API test", func() {
 
 		Context("Auth Tests", func() {
 			It("Should fail if the api key is missing", func() {
-				err, sc := postInvalidRequest("http://127.0.0.1:9090/models/available")
+				err, sc := postInvalidRequest(testHTTPBase + "/models/available")
 				Expect(err).ToNot(BeNil())
 				Expect(sc).To(Equal(401))
 			})
@@ -427,7 +427,7 @@ var _ = Describe("API test", func() {
 		Context("URL routing Tests", func() {
 			It("Should support reverse-proxy when unauthenticated", func() {
 
-				err, sc, body := getRequest("http://127.0.0.1:9090/myprefix/", http.Header{
+				err, sc, body := getRequest(testHTTPBase+"/myprefix/", http.Header{
 					"X-Forwarded-Proto":  {"https"},
 					"X-Forwarded-Host":   {"example.org"},
 					"X-Forwarded-Prefix": {"/myprefix/"},
@@ -441,7 +441,7 @@ var _ = Describe("API test", func() {
 
 			It("Should support reverse-proxy when authenticated", func() {
 
-				err, sc, body := getRequest("http://127.0.0.1:9090/myprefix/", http.Header{
+				err, sc, body := getRequest(testHTTPBase+"/myprefix/", http.Header{
 					"Authorization":      {bearerKey},
 					"X-Forwarded-Proto":  {"https"},
 					"X-Forwarded-Host":   {"example.org"},
@@ -459,7 +459,7 @@ var _ = Describe("API test", func() {
 			// requests them through the proxy.
 			It("Should support reverse-proxy when prefix is stripped by the proxy", func() {
 
-				err, sc, body := getRequest("http://127.0.0.1:9090/app", http.Header{
+				err, sc, body := getRequest(testHTTPBase+"/app", http.Header{
 					"X-Forwarded-Proto":  {"https"},
 					"X-Forwarded-Host":   {"example.org"},
 					"X-Forwarded-Prefix": {"/myprefix"},
@@ -477,7 +477,7 @@ var _ = Describe("API test", func() {
 			// from a foreign origin. BasePathPrefix must reject these via
 			// SafeForwardedPrefix and fall back to "/".
 			It("Should ignore an unsafe X-Forwarded-Prefix and not poison asset URLs", func() {
-				err, sc, body := getRequest("http://127.0.0.1:9090/app", http.Header{
+				err, sc, body := getRequest(testHTTPBase+"/app", http.Header{
 					"X-Forwarded-Proto":  {"https"},
 					"X-Forwarded-Host":   {"example.org"},
 					"X-Forwarded-Prefix": {"//evil.com"},
@@ -492,13 +492,13 @@ var _ = Describe("API test", func() {
 		Context("Applying models", func() {
 
 			It("applies models from a gallery", func() {
-				models, err := getModels("http://127.0.0.1:9090/models/available")
+				models, err := getModels(testHTTPBase + "/models/available")
 				Expect(err).To(BeNil())
 				Expect(len(models)).To(Equal(2), fmt.Sprint(models))
 				Expect(models[0].Installed).To(BeFalse(), fmt.Sprint(models))
 				Expect(models[1].Installed).To(BeFalse(), fmt.Sprint(models))
 
-				response := postModelApplyRequest("http://127.0.0.1:9090/models/apply", modelApplyRequest{
+				response := postModelApplyRequest(testHTTPBase+"/models/apply", modelApplyRequest{
 					ID: "test@bert2",
 				})
 
@@ -507,7 +507,7 @@ var _ = Describe("API test", func() {
 				uuid := response["uuid"].(string)
 				resp := map[string]any{}
 				Eventually(func() bool {
-					response := getModelStatus("http://127.0.0.1:9090/models/jobs/" + uuid)
+					response := getModelStatus(testHTTPBase + "/models/jobs/" + uuid)
 					fmt.Println(response)
 					resp = response
 					return response["processed"].(bool)
@@ -526,7 +526,7 @@ var _ = Describe("API test", func() {
 				Expect(content["usage"]).To(ContainSubstring("You can test this model with curl like this"))
 				Expect(content["foo"]).To(Equal("bar"))
 
-				models, err = getModels("http://127.0.0.1:9090/models/available")
+				models, err = getModels(testHTTPBase + "/models/available")
 				Expect(err).To(BeNil())
 				Expect(len(models)).To(Equal(2), fmt.Sprint(models))
 				Expect(models[0].Name).To(Or(Equal("bert"), Equal("bert2")))
@@ -541,7 +541,7 @@ var _ = Describe("API test", func() {
 			})
 			It("overrides models", func() {
 
-				response := postModelApplyRequest("http://127.0.0.1:9090/models/apply", modelApplyRequest{
+				response := postModelApplyRequest(testHTTPBase+"/models/apply", modelApplyRequest{
 					URL:  bertEmbeddingsURL,
 					Name: "bert",
 					Overrides: map[string]any{
@@ -554,7 +554,7 @@ var _ = Describe("API test", func() {
 				uuid := response["uuid"].(string)
 
 				Eventually(func() bool {
-					response := getModelStatus("http://127.0.0.1:9090/models/jobs/" + uuid)
+					response := getModelStatus(testHTTPBase + "/models/jobs/" + uuid)
 					return response["processed"].(bool)
 				}, "360s", "10s").Should(Equal(true))
 
@@ -567,7 +567,7 @@ var _ = Describe("API test", func() {
 				Expect(content["backend"]).To(Equal("llama"))
 			})
 			It("apply models without overrides", func() {
-				response := postModelApplyRequest("http://127.0.0.1:9090/models/apply", modelApplyRequest{
+				response := postModelApplyRequest(testHTTPBase+"/models/apply", modelApplyRequest{
 					URL:       bertEmbeddingsURL,
 					Name:      "bert",
 					Overrides: map[string]any{},
@@ -578,7 +578,7 @@ var _ = Describe("API test", func() {
 				uuid := response["uuid"].(string)
 
 				Eventually(func() bool {
-					response := getModelStatus("http://127.0.0.1:9090/models/jobs/" + uuid)
+					response := getModelStatus(testHTTPBase + "/models/jobs/" + uuid)
 					return response["processed"].(bool)
 				}, "360s", "10s").Should(Equal(true))
 
@@ -622,14 +622,14 @@ parameters:
 				}
 
 				var response schema.GalleryResponse
-				err := postRequestResponseJSON("http://127.0.0.1:9090/models/import-uri", &importReq, &response)
+				err := postRequestResponseJSON(testHTTPBase+"/models/import-uri", &importReq, &response)
 				Expect(err).ToNot(HaveOccurred())
 				Expect(response.ID).ToNot(BeEmpty())
 
 				uuid := response.ID
 				resp := map[string]any{}
 				Eventually(func() bool {
-					response := getModelStatus("http://127.0.0.1:9090/models/jobs/" + uuid)
+					response := getModelStatus(testHTTPBase + "/models/jobs/" + uuid)
 					resp = response
 					return response["processed"].(bool)
 				}, "360s", "10s").Should(Equal(true))
@@ -657,7 +657,7 @@ parameters:
 				}
 
 				var response schema.GalleryResponse
-				err := postRequestResponseJSON("http://127.0.0.1:9090/models/import-uri", &importReq, &response)
+				err := postRequestResponseJSON(testHTTPBase+"/models/import-uri", &importReq, &response)
 				// The endpoint should return an error immediately
 				Expect(err).To(HaveOccurred())
 				Expect(err.Error()).To(ContainSubstring("failed to discover model config"))
@@ -693,14 +693,14 @@ parameters:
 				}
 
 				var response schema.GalleryResponse
-				err := postRequestResponseJSON("http://127.0.0.1:9090/models/import-uri", &importReq, &response)
+				err := postRequestResponseJSON(testHTTPBase+"/models/import-uri", &importReq, &response)
 				Expect(err).ToNot(HaveOccurred())
 				Expect(response.ID).ToNot(BeEmpty())
 
 				uuid := response.ID
 				resp := map[string]any{}
 				Eventually(func() bool {
-					response := getModelStatus("http://127.0.0.1:9090/models/jobs/" + uuid)
+					response := getModelStatus(testHTTPBase + "/models/jobs/" + uuid)
 					resp = response
 					return response["processed"].(bool)
 				}, "360s", "10s").Should(Equal(true))
@@ -751,13 +751,13 @@ parameters:
 			app, err = API(localAIApp)
 			Expect(err).ToNot(HaveOccurred())
 			go func() {
-				if err := app.Start("127.0.0.1:9090"); err != nil && err != http.ErrServerClosed {
+				if err := app.Start(testHTTPAddr); err != nil && err != http.ErrServerClosed {
 					xlog.Error("server error", "error", err)
 				}
 			}()
 
 			defaultConfig := openai.DefaultConfig("")
-			defaultConfig.BaseURL = "http://127.0.0.1:9090/v1"
+			defaultConfig.BaseURL = testHTTPBase + "/v1"
 
 			client2 = openaigo.NewClient("")
 			client2.BaseURL = defaultConfig.BaseURL
@@ -801,7 +801,7 @@ parameters:
 			// Mock-backend is registered via SetExternalBackend so it appears
 			// alongside any built-in entries; verifying that string proves the
 			// endpoint is wired up regardless of which real backends exist.
-			resp, err := http.Get("http://127.0.0.1:9090/system")
+			resp, err := http.Get(testHTTPBase + "/system")
 			Expect(err).ToNot(HaveOccurred())
 			Expect(resp.StatusCode).To(Equal(200))
 			dat, err := io.ReadAll(resp.Body)
@@ -824,14 +824,14 @@ parameters:
 				}
 
 				var createResp map[string]any
-				err := postRequestResponseJSON("http://127.0.0.1:9090/api/agent/tasks", &taskBody, &createResp)
+				err := postRequestResponseJSON(testHTTPBase+"/api/agent/tasks", &taskBody, &createResp)
 				Expect(err).ToNot(HaveOccurred())
 				Expect(createResp["id"]).ToNot(BeEmpty())
 				taskID := createResp["id"].(string)
 
 				// Get the task
 				var task schema.Task
-				resp, err := http.Get("http://127.0.0.1:9090/api/agent/tasks/" + taskID)
+				resp, err := http.Get(testHTTPBase + "/api/agent/tasks/" + taskID)
 				Expect(err).ToNot(HaveOccurred())
 				Expect(resp.StatusCode).To(Equal(200))
 				body, _ := io.ReadAll(resp.Body)
@@ -839,7 +839,7 @@ parameters:
 				Expect(task.Name).To(Equal("Test Task"))
 
 				// List tasks
-				resp, err = http.Get("http://127.0.0.1:9090/api/agent/tasks")
+				resp, err = http.Get(testHTTPBase + "/api/agent/tasks")
 				Expect(err).ToNot(HaveOccurred())
 				Expect(resp.StatusCode).To(Equal(200))
 				var tasks []schema.Task
@@ -849,18 +849,18 @@ parameters:
 
 				// Update task
 				taskBody["name"] = "Updated Task"
-				err = putRequestJSON("http://127.0.0.1:9090/api/agent/tasks/"+taskID, &taskBody)
+				err = putRequestJSON(testHTTPBase+"/api/agent/tasks/"+taskID, &taskBody)
 				Expect(err).ToNot(HaveOccurred())
 
 				// Verify update
-				resp, err = http.Get("http://127.0.0.1:9090/api/agent/tasks/" + taskID)
+				resp, err = http.Get(testHTTPBase + "/api/agent/tasks/" + taskID)
 				Expect(err).ToNot(HaveOccurred())
 				body, _ = io.ReadAll(resp.Body)
 				json.Unmarshal(body, &task)
 				Expect(task.Name).To(Equal("Updated Task"))
 
 				// Delete task
-				req, _ := http.NewRequest("DELETE", "http://127.0.0.1:9090/api/agent/tasks/"+taskID, nil)
+				req, _ := http.NewRequest("DELETE", testHTTPBase+"/api/agent/tasks/"+taskID, nil)
 				req.Header.Set("Authorization", bearerKey)
 				resp, err = http.DefaultClient.Do(req)
 				Expect(err).ToNot(HaveOccurred())
@@ -877,7 +877,7 @@ parameters:
 				}
 
 				var createResp map[string]any
-				err := postRequestResponseJSON("http://127.0.0.1:9090/api/agent/tasks", &taskBody, &createResp)
+				err := postRequestResponseJSON(testHTTPBase+"/api/agent/tasks", &taskBody, &createResp)
 				Expect(err).ToNot(HaveOccurred())
 				taskID := createResp["id"].(string)
 
@@ -888,14 +888,14 @@ parameters:
 				}
 
 				var jobResp schema.JobExecutionResponse
-				err = postRequestResponseJSON("http://127.0.0.1:9090/api/agent/jobs/execute", &jobBody, &jobResp)
+				err = postRequestResponseJSON(testHTTPBase+"/api/agent/jobs/execute", &jobBody, &jobResp)
 				Expect(err).ToNot(HaveOccurred())
 				Expect(jobResp.JobID).ToNot(BeEmpty())
 				jobID := jobResp.JobID
 
 				// Get job status
 				var job schema.Job
-				resp, err := http.Get("http://127.0.0.1:9090/api/agent/jobs/" + jobID)
+				resp, err := http.Get(testHTTPBase + "/api/agent/jobs/" + jobID)
 				Expect(err).ToNot(HaveOccurred())
 				Expect(resp.StatusCode).To(Equal(200))
 				body, _ := io.ReadAll(resp.Body)
@@ -904,7 +904,7 @@ parameters:
 				Expect(job.TaskID).To(Equal(taskID))
 
 				// List jobs
-				resp, err = http.Get("http://127.0.0.1:9090/api/agent/jobs")
+				resp, err = http.Get(testHTTPBase + "/api/agent/jobs")
 				Expect(err).ToNot(HaveOccurred())
 				Expect(resp.StatusCode).To(Equal(200))
 				var jobs []schema.Job
@@ -914,7 +914,7 @@ parameters:
 
 				// Cancel job (if still pending/running)
 				if job.Status == schema.JobStatusPending || job.Status == schema.JobStatusRunning {
-					req, _ := http.NewRequest("POST", "http://127.0.0.1:9090/api/agent/jobs/"+jobID+"/cancel", nil)
+					req, _ := http.NewRequest("POST", testHTTPBase+"/api/agent/jobs/"+jobID+"/cancel", nil)
 					req.Header.Set("Authorization", bearerKey)
 					resp, err = http.DefaultClient.Do(req)
 					Expect(err).ToNot(HaveOccurred())
@@ -932,13 +932,13 @@ parameters:
 				}
 
 				var createResp map[string]any
-				err := postRequestResponseJSON("http://127.0.0.1:9090/api/agent/tasks", &taskBody, &createResp)
+				err := postRequestResponseJSON(testHTTPBase+"/api/agent/tasks", &taskBody, &createResp)
 				Expect(err).ToNot(HaveOccurred())
 
 				// Execute by name
 				paramsBody := map[string]string{"param1": "value1"}
 				var jobResp schema.JobExecutionResponse
-				err = postRequestResponseJSON("http://127.0.0.1:9090/api/agent/tasks/Named Task/execute", &paramsBody, &jobResp)
+				err = postRequestResponseJSON(testHTTPBase+"/api/agent/tasks/Named Task/execute", &paramsBody, &jobResp)
 				Expect(err).ToNot(HaveOccurred())
 				Expect(jobResp.JobID).ToNot(BeEmpty())
 			})
@@ -998,13 +998,13 @@ parameters:
 			Expect(err).ToNot(HaveOccurred())
 
 			go func() {
-				if err := app.Start("127.0.0.1:9090"); err != nil && err != http.ErrServerClosed {
+				if err := app.Start(testHTTPAddr); err != nil && err != http.ErrServerClosed {
 					xlog.Error("server error", "error", err)
 				}
 			}()
 
 			defaultConfig := openai.DefaultConfig("")
-			defaultConfig.BaseURL = "http://127.0.0.1:9090/v1"
+			defaultConfig.BaseURL = testHTTPBase + "/v1"
 			client2 = openaigo.NewClient("")
 			client2.BaseURL = defaultConfig.BaseURL
 			// Wait for API to be ready

core/http/endpoints/localai/backend.go

@@ -25,6 +25,10 @@ var knownPrefOnlyBackends = []schema.KnownBackend{
 	// Text LLM
 	// ds4: antirez/ds4 - single-model DeepSeek V4 Flash engine; auto-detected via DS4Importer
 	{Name: "ds4", Modality: "text", AutoDetect: false, Description: "antirez/ds4 DeepSeek V4 Flash engine (auto-detected; pref-only fallback)"},
+	// dllm consumes GGUF weights like llama-cpp does, but only for the
+	// DiffusionGemma architecture - auto-detecting on .gguf would shadow
+	// llama-cpp, so it stays preference-only.
+	{Name: "dllm", Modality: "text", AutoDetect: false, Description: "dllm.cpp DiffusionGemma block-diffusion engine (preference-only)"},
 	{Name: "sglang", Modality: "text", AutoDetect: false, Description: "SGLang runtime (preference-only)"},
 	{Name: "tinygrad", Modality: "text", AutoDetect: false, Description: "tinygrad runtime (preference-only)"},
 	{Name: "trl", Modality: "text", AutoDetect: false, Description: "Transformers Reinforcement Learning (preference-only)"},

core/http/endpoints/localai/backend_test.go

@@ -135,6 +135,7 @@ var _ = Describe("Backend Endpoints", func() {
 				Expect(entry.Modality).To(Equal(modality))
 			}
 
+			expectPrefOnly("dllm", "text")
 			expectPrefOnly("sglang", "text")
 			expectPrefOnly("tinygrad", "text")
 			expectPrefOnly("trl", "text")

core/http/http_suite_test.go

@@ -21,6 +21,20 @@ var (
 	mockBackendPath string
 )
 
+// testHTTPAddr is the listen address used by specs that start a full HTTP
+// server. Configurable so the suite can run on machines where the default
+// port is taken by an unrelated service (override: LOCALAI_TEST_HTTP_PORT).
+var testHTTPAddr = func() string {
+	port := os.Getenv("LOCALAI_TEST_HTTP_PORT")
+	if port == "" {
+		port = "9090"
+	}
+	return "127.0.0.1:" + port
+}()
+
+// testHTTPBase is the matching http://host:port prefix for client requests.
+var testHTTPBase = "http://" + testHTTPAddr
+
 // findMockBackendBinary locates the mock-backend binary built by
 // `make build-mock-backend`. Mirrors the lookup used by
 // tests/e2e/e2e_suite_test.go so both suites consume the same artifact.

core/http/openresponses_test.go

@@ -59,14 +59,14 @@ var _ = Describe("Open Responses API", func() {
 			Expect(err).ToNot(HaveOccurred())
 
 			go func() {
-				if err := app.Start("127.0.0.1:9090"); err != nil && err != http.ErrServerClosed {
+				if err := app.Start(testHTTPAddr); err != nil && err != http.ErrServerClosed {
 					xlog.Error("server error", "error", err)
 				}
 			}()
 
 			// Wait for API to be ready
 			Eventually(func() error {
-				resp, err := http.Get("http://127.0.0.1:9090/healthz")
+				resp, err := http.Get(testHTTPBase + "/healthz")
 				if err != nil {
 					return err
 				}
@@ -95,7 +95,7 @@ var _ = Describe("Open Responses API", func() {
 				payload, err := json.Marshal(reqBody)
 				Expect(err).ToNot(HaveOccurred())
 
-				req, err := http.NewRequest("POST", "http://127.0.0.1:9090/v1/responses", bytes.NewBuffer(payload))
+				req, err := http.NewRequest("POST", testHTTPBase+"/v1/responses", bytes.NewBuffer(payload))
 				Expect(err).ToNot(HaveOccurred())
 				req.Header.Set("Content-Type", "application/json")
 				req.Header.Set("Authorization", bearerKey)
@@ -118,7 +118,7 @@ var _ = Describe("Open Responses API", func() {
 				payload, err := json.Marshal(reqBody)
 				Expect(err).ToNot(HaveOccurred())
 
-				req, err := http.NewRequest("POST", "http://127.0.0.1:9090/v1/responses", bytes.NewBuffer(payload))
+				req, err := http.NewRequest("POST", testHTTPBase+"/v1/responses", bytes.NewBuffer(payload))
 				Expect(err).ToNot(HaveOccurred())
 				req.Header.Set("Content-Type", "application/json")
 				req.Header.Set("Authorization", bearerKey)
@@ -143,7 +143,7 @@ var _ = Describe("Open Responses API", func() {
 				payload, err := json.Marshal(reqBody)
 				Expect(err).ToNot(HaveOccurred())
 
-				req, err := http.NewRequest("POST", "http://127.0.0.1:9090/v1/responses", bytes.NewBuffer(payload))
+				req, err := http.NewRequest("POST", testHTTPBase+"/v1/responses", bytes.NewBuffer(payload))
 				Expect(err).ToNot(HaveOccurred())
 				req.Header.Set("Content-Type", "application/json")
 				req.Header.Set("Authorization", bearerKey)
@@ -168,7 +168,7 @@ var _ = Describe("Open Responses API", func() {
 				payload, err := json.Marshal(reqBody)
 				Expect(err).ToNot(HaveOccurred())
 
-				req, err := http.NewRequest("POST", "http://127.0.0.1:9090/v1/responses", bytes.NewBuffer(payload))
+				req, err := http.NewRequest("POST", testHTTPBase+"/v1/responses", bytes.NewBuffer(payload))
 				Expect(err).ToNot(HaveOccurred())
 				req.Header.Set("Content-Type", "application/json")
 				req.Header.Set("Authorization", bearerKey)
@@ -196,7 +196,7 @@ var _ = Describe("Open Responses API", func() {
 				payload, err := json.Marshal(reqBody)
 				Expect(err).ToNot(HaveOccurred())
 
-				req, err := http.NewRequest("POST", "http://127.0.0.1:9090/v1/responses", bytes.NewBuffer(payload))
+				req, err := http.NewRequest("POST", testHTTPBase+"/v1/responses", bytes.NewBuffer(payload))
 				Expect(err).ToNot(HaveOccurred())
 				req.Header.Set("Content-Type", "application/json")
 				req.Header.Set("Authorization", bearerKey)
@@ -241,7 +241,7 @@ var _ = Describe("Open Responses API", func() {
 				payload, err := json.Marshal(reqBody)
 				Expect(err).ToNot(HaveOccurred())
 
-				req, err := http.NewRequest("POST", "http://127.0.0.1:9090/v1/responses", bytes.NewBuffer(payload))
+				req, err := http.NewRequest("POST", testHTTPBase+"/v1/responses", bytes.NewBuffer(payload))
 				Expect(err).ToNot(HaveOccurred())
 				req.Header.Set("Content-Type", "application/json")
 				req.Header.Set("Authorization", bearerKey)
@@ -269,7 +269,7 @@ var _ = Describe("Open Responses API", func() {
 				payload, err := json.Marshal(reqBody)
 				Expect(err).ToNot(HaveOccurred())
 
-				req, err := http.NewRequest("POST", "http://127.0.0.1:9090/v1/responses", bytes.NewBuffer(payload))
+				req, err := http.NewRequest("POST", testHTTPBase+"/v1/responses", bytes.NewBuffer(payload))
 				Expect(err).ToNot(HaveOccurred())
 				req.Header.Set("Content-Type", "application/json")
 				req.Header.Set("Authorization", bearerKey)
@@ -297,7 +297,7 @@ var _ = Describe("Open Responses API", func() {
 				payload, err := json.Marshal(reqBody)
 				Expect(err).ToNot(HaveOccurred())
 
-				req, err := http.NewRequest("POST", "http://127.0.0.1:9090/v1/responses", bytes.NewBuffer(payload))
+				req, err := http.NewRequest("POST", testHTTPBase+"/v1/responses", bytes.NewBuffer(payload))
 				Expect(err).ToNot(HaveOccurred())
 				req.Header.Set("Content-Type", "application/json")
 				req.Header.Set("Authorization", bearerKey)
@@ -328,7 +328,7 @@ var _ = Describe("Open Responses API", func() {
 				payload, err := json.Marshal(reqBody)
 				Expect(err).ToNot(HaveOccurred())
 
-				req, err := http.NewRequest("POST", "http://127.0.0.1:9090/v1/responses", bytes.NewBuffer(payload))
+				req, err := http.NewRequest("POST", testHTTPBase+"/v1/responses", bytes.NewBuffer(payload))
 				Expect(err).ToNot(HaveOccurred())
 				req.Header.Set("Content-Type", "application/json")
 				req.Header.Set("Authorization", bearerKey)
@@ -358,7 +358,7 @@ var _ = Describe("Open Responses API", func() {
 				payload, err := json.Marshal(reqBody)
 				Expect(err).ToNot(HaveOccurred())
 
-				req, err := http.NewRequest("POST", "http://127.0.0.1:9090/v1/responses", bytes.NewBuffer(payload))
+				req, err := http.NewRequest("POST", testHTTPBase+"/v1/responses", bytes.NewBuffer(payload))
 				Expect(err).ToNot(HaveOccurred())
 				req.Header.Set("Content-Type", "application/json")
 				req.Header.Set("Authorization", bearerKey)
@@ -386,7 +386,7 @@ var _ = Describe("Open Responses API", func() {
 				payload, err := json.Marshal(reqBody)
 				Expect(err).ToNot(HaveOccurred())
 
-				req, err := http.NewRequest("POST", "http://127.0.0.1:9090/v1/responses", bytes.NewBuffer(payload))
+				req, err := http.NewRequest("POST", testHTTPBase+"/v1/responses", bytes.NewBuffer(payload))
 				Expect(err).ToNot(HaveOccurred())
 				req.Header.Set("Content-Type", "application/json")
 				req.Header.Set("Authorization", bearerKey)
@@ -418,7 +418,7 @@ var _ = Describe("Open Responses API", func() {
 				payload, err := json.Marshal(reqBody)
 				Expect(err).ToNot(HaveOccurred())
 
-				req, err := http.NewRequest("POST", "http://127.0.0.1:9090/v1/responses", bytes.NewBuffer(payload))
+				req, err := http.NewRequest("POST", testHTTPBase+"/v1/responses", bytes.NewBuffer(payload))
 				Expect(err).ToNot(HaveOccurred())
 				req.Header.Set("Content-Type", "application/json")
 				req.Header.Set("Authorization", bearerKey)
@@ -454,7 +454,7 @@ var _ = Describe("Open Responses API", func() {
 				payload, err := json.Marshal(reqBody)
 				Expect(err).ToNot(HaveOccurred())
 
-				req, err := http.NewRequest("POST", "http://127.0.0.1:9090/v1/responses", bytes.NewBuffer(payload))
+				req, err := http.NewRequest("POST", testHTTPBase+"/v1/responses", bytes.NewBuffer(payload))
 				Expect(err).ToNot(HaveOccurred())
 				req.Header.Set("Content-Type", "application/json")
 				req.Header.Set("Authorization", bearerKey)
@@ -490,7 +490,7 @@ var _ = Describe("Open Responses API", func() {
 				payload, err := json.Marshal(reqBody)
 				Expect(err).ToNot(HaveOccurred())
 
-				req, err := http.NewRequest("POST", "http://127.0.0.1:9090/v1/responses", bytes.NewBuffer(payload))
+				req, err := http.NewRequest("POST", testHTTPBase+"/v1/responses", bytes.NewBuffer(payload))
 				Expect(err).ToNot(HaveOccurred())
 				req.Header.Set("Content-Type", "application/json")
 				req.Header.Set("Authorization", bearerKey)
@@ -539,7 +539,7 @@ var _ = Describe("Open Responses API", func() {
 				payload, err := json.Marshal(reqBody)
 				Expect(err).ToNot(HaveOccurred())
 
-				req, err := http.NewRequest("POST", "http://127.0.0.1:9090/v1/responses", bytes.NewBuffer(payload))
+				req, err := http.NewRequest("POST", testHTTPBase+"/v1/responses", bytes.NewBuffer(payload))
 				Expect(err).ToNot(HaveOccurred())
 				req.Header.Set("Content-Type", "application/json")
 				req.Header.Set("Authorization", bearerKey)
@@ -590,7 +590,7 @@ var _ = Describe("Open Responses API", func() {
 				payload, err := json.Marshal(reqBody)
 				Expect(err).ToNot(HaveOccurred())
 
-				req, err := http.NewRequest("POST", "http://127.0.0.1:9090/v1/responses", bytes.NewBuffer(payload))
+				req, err := http.NewRequest("POST", testHTTPBase+"/v1/responses", bytes.NewBuffer(payload))
 				Expect(err).ToNot(HaveOccurred())
 				req.Header.Set("Content-Type", "application/json")
 				req.Header.Set("Authorization", bearerKey)
@@ -624,7 +624,7 @@ var _ = Describe("Open Responses API", func() {
 				payload, err := json.Marshal(reqBody)
 				Expect(err).ToNot(HaveOccurred())
 
-				req, err := http.NewRequest("POST", "http://127.0.0.1:9090/v1/responses", bytes.NewBuffer(payload))
+				req, err := http.NewRequest("POST", testHTTPBase+"/v1/responses", bytes.NewBuffer(payload))
 				Expect(err).ToNot(HaveOccurred())
 				req.Header.Set("Content-Type", "application/json")
 				req.Header.Set("Authorization", bearerKey)
@@ -658,7 +658,7 @@ var _ = Describe("Open Responses API", func() {
 				payload, err := json.Marshal(reqBody)
 				Expect(err).ToNot(HaveOccurred())
 
-				req, err := http.NewRequest("POST", "http://127.0.0.1:9090/v1/responses", bytes.NewBuffer(payload))
+				req, err := http.NewRequest("POST", testHTTPBase+"/v1/responses", bytes.NewBuffer(payload))
 				Expect(err).ToNot(HaveOccurred())
 				req.Header.Set("Content-Type", "application/json")
 				req.Header.Set("Authorization", bearerKey)
@@ -680,7 +680,7 @@ var _ = Describe("Open Responses API", func() {
 				payload, err := json.Marshal(reqBody)
 				Expect(err).ToNot(HaveOccurred())
 
-				req, err := http.NewRequest("POST", "http://127.0.0.1:9090/v1/responses", bytes.NewBuffer(payload))
+				req, err := http.NewRequest("POST", testHTTPBase+"/v1/responses", bytes.NewBuffer(payload))
 				Expect(err).ToNot(HaveOccurred())
 				req.Header.Set("Content-Type", "application/json")
 				req.Header.Set("Authorization", bearerKey)
@@ -727,7 +727,7 @@ var _ = Describe("Open Responses API", func() {
 				payload, err := json.Marshal(reqBody)
 				Expect(err).ToNot(HaveOccurred())
 
-				req, err := http.NewRequest("POST", "http://127.0.0.1:9090/v1/responses", bytes.NewBuffer(payload))
+				req, err := http.NewRequest("POST", testHTTPBase+"/v1/responses", bytes.NewBuffer(payload))
 				Expect(err).ToNot(HaveOccurred())
 				req.Header.Set("Content-Type", "application/json")
 				req.Header.Set("Authorization", bearerKey)
@@ -756,7 +756,7 @@ var _ = Describe("Open Responses API", func() {
 				payload, err := json.Marshal(reqBody)
 				Expect(err).ToNot(HaveOccurred())
 
-				req, err := http.NewRequest("POST", "http://127.0.0.1:9090/v1/responses", bytes.NewBuffer(payload))
+				req, err := http.NewRequest("POST", testHTTPBase+"/v1/responses", bytes.NewBuffer(payload))
 				Expect(err).ToNot(HaveOccurred())
 				req.Header.Set("Content-Type", "application/json")
 				req.Header.Set("Authorization", bearerKey)
@@ -799,7 +799,7 @@ var _ = Describe("Open Responses API", func() {
 				payload, err := json.Marshal(reqBody)
 				Expect(err).ToNot(HaveOccurred())
 
-				req, err := http.NewRequest("POST", "http://127.0.0.1:9090/v1/responses", bytes.NewBuffer(payload))
+				req, err := http.NewRequest("POST", testHTTPBase+"/v1/responses", bytes.NewBuffer(payload))
 				Expect(err).ToNot(HaveOccurred())
 				req.Header.Set("Content-Type", "application/json")
 				req.Header.Set("Authorization", bearerKey)
@@ -835,7 +835,7 @@ var _ = Describe("Open Responses API", func() {
 				payload1, err := json.Marshal(reqBody1)
 				Expect(err).ToNot(HaveOccurred())
 
-				req1, err := http.NewRequest("POST", "http://127.0.0.1:9090/v1/responses", bytes.NewBuffer(payload1))
+				req1, err := http.NewRequest("POST", testHTTPBase+"/v1/responses", bytes.NewBuffer(payload1))
 				Expect(err).ToNot(HaveOccurred())
 				req1.Header.Set("Content-Type", "application/json")
 				req1.Header.Set("Authorization", bearerKey)
@@ -869,7 +869,7 @@ var _ = Describe("Open Responses API", func() {
 				payload2, err := json.Marshal(reqBody2)
 				Expect(err).ToNot(HaveOccurred())
 
-				req2, err := http.NewRequest("POST", "http://127.0.0.1:9090/v1/responses", bytes.NewBuffer(payload2))
+				req2, err := http.NewRequest("POST", testHTTPBase+"/v1/responses", bytes.NewBuffer(payload2))
 				Expect(err).ToNot(HaveOccurred())
 				req2.Header.Set("Content-Type", "application/json")
 				req2.Header.Set("Authorization", bearerKey)
@@ -897,7 +897,7 @@ var _ = Describe("Open Responses API", func() {
 				payload, err := json.Marshal(reqBody)
 				Expect(err).ToNot(HaveOccurred())
 
-				req, err := http.NewRequest("POST", "http://127.0.0.1:9090/v1/responses", bytes.NewBuffer(payload))
+				req, err := http.NewRequest("POST", testHTTPBase+"/v1/responses", bytes.NewBuffer(payload))
 				Expect(err).ToNot(HaveOccurred())
 				req.Header.Set("Content-Type", "application/json")
 				req.Header.Set("Authorization", bearerKey)
@@ -933,7 +933,7 @@ var _ = Describe("Open Responses API", func() {
 				payload1, err := json.Marshal(reqBody1)
 				Expect(err).ToNot(HaveOccurred())
 
-				req1, err := http.NewRequest("POST", "http://127.0.0.1:9090/v1/responses", bytes.NewBuffer(payload1))
+				req1, err := http.NewRequest("POST", testHTTPBase+"/v1/responses", bytes.NewBuffer(payload1))
 				Expect(err).ToNot(HaveOccurred())
 				req1.Header.Set("Content-Type", "application/json")
 				req1.Header.Set("Authorization", bearerKey)
@@ -983,7 +983,7 @@ var _ = Describe("Open Responses API", func() {
 				payload2, err := json.Marshal(reqBody2)
 				Expect(err).ToNot(HaveOccurred())
 
-				req2, err := http.NewRequest("POST", "http://127.0.0.1:9090/v1/responses", bytes.NewBuffer(payload2))
+				req2, err := http.NewRequest("POST", testHTTPBase+"/v1/responses", bytes.NewBuffer(payload2))
 				Expect(err).ToNot(HaveOccurred())
 				req2.Header.Set("Content-Type", "application/json")
 				req2.Header.Set("Authorization", bearerKey)
@@ -1009,7 +1009,7 @@ var _ = Describe("Open Responses API", func() {
 				payload, err := json.Marshal(reqBody)
 				Expect(err).ToNot(HaveOccurred())
 
-				req, err := http.NewRequest("POST", "http://127.0.0.1:9090/v1/responses", bytes.NewBuffer(payload))
+				req, err := http.NewRequest("POST", testHTTPBase+"/v1/responses", bytes.NewBuffer(payload))
 				Expect(err).ToNot(HaveOccurred())
 				req.Header.Set("Content-Type", "application/json")
 				req.Header.Set("Authorization", bearerKey)

docs/content/features/text-generation.md

@@ -655,6 +655,126 @@ The `cache_type_k` / `cache_type_v` fields map to llama.cpp's `-ctk` / `-ctv` fl
 - [Tracked branch: `feature/turboquant-kv-cache`](https://github.com/TheTom/llama-cpp-turboquant/tree/feature/turboquant-kv-cache)
 
 
+### dllm (DiffusionGemma block-diffusion)
+
+[dllm.cpp](https://github.com/mudler/dllm.cpp) is a standalone C++/ggml engine for **DiffusionGemma** block-diffusion language models (GGUF weights). Instead of sampling one token at a time, generation works on fixed-size token **canvases** (256 tokens for the published model): each canvas is iteratively denoised with the Entropy-Bound (EB) sampler, committed as a whole block, and committed blocks feed back as prompt for the next canvas. LocalAI wraps the engine with a native Go backend (`dllm`) that also owns chat templating and output parsing: the model's thought channels and tool calls stream natively as `reasoning_content` and `tool_calls` deltas, with no jinja template involved.
+
+{{% notice note %}}
+
+This backend is **experimental**, and the engine does not yet have a prompt-KV prefix cache: every denoise step recomputes the full prompt+canvas forward pass, so throughput is low (~0.15 tok/s at default settings on a single GB10 GPU) and drops further as the context fills up. The prefix cache is the planned fix in upstream dllm.cpp.
+
+{{% /notice %}}
+
+#### Features
+
+- [📖 Text generation (GPT)]({{%relref "features/text-generation" %}})
+- [🔥 OpenAI functions]({{%relref "features/openai-functions" %}}) - tool calls are parsed natively by the backend (gemma4 `<|tool_call>` markers), not by LocalAI's grammar/regex fallback
+- Reasoning - opt-in thinking streams as `reasoning_content` (see below)
+- Request cancellation - disconnecting the client (or a request timeout) aborts the in-flight generation server-side, so an abandoned slow run does not keep the GPU busy
+
+#### Supported platforms
+
+| Flavor | Hardware |
+|---|---|
+| `cpu-dllm` | CPU (amd64 + arm64) - functional but very slow on the 26B model; mainly useful for wiring tests |
+| `cuda13-dllm` | NVIDIA CUDA 13 (amd64) |
+| `cuda13-nvidia-l4t-arm64-dllm` | NVIDIA L4T arm64 (Jetson / DGX Spark GB10) |
+
+macOS/Metal is not available yet.
+
+#### Setup
+
+The easiest path is the model gallery; the entry installs the backend and the model together:
+
+```bash
+local-ai models install diffusiongemma-26b-a4b-it
+```
+
+Or configure it manually with a YAML file pointing at the GGUF (BF16 is the only published file the engine's validation is calibrated for; the model card flags quantized MoE exports as problematic):
+
+```yaml
+name: diffusiongemma
+backend: dllm
+parameters:
+  model: diffusiongemma-26B-A4B-it-BF16.gguf
+context_size: 4096
+stopwords:
+  - <turn|>
+# The backend parses tool calls natively; keep LocalAI's generated tool
+# grammar from overriding that pipeline.
+function:
+  grammar:
+    disable: true
+template:
+  use_tokenizer_template: true
+```
+
+`use_tokenizer_template: true` is what routes chat requests through the backend's native gemma4 renderer/parser (messages and tools in, `content`/`reasoning_content`/`tool_calls` out). Without it, your own prompt template output is passed to the engine verbatim and the raw model text comes back as plain content.
+
+#### Backend options
+
+Model-level generation options go in the `options:` array (format: `key:value`), like other backends:
+
+```yaml
+options:
+  - eb_max_steps:24
+  - kv_cache:auto
+```
+
+| Option | Type | Default | Description |
+|--------|------|---------|-------------|
+| `blocks` | integer | unset | Generation budget in whole diffusion canvases (`blocks * canvas_length` tokens, 256 per canvas for the published model). Must be >= 1. When both `blocks` and a token budget are present, `blocks` wins. |
+| `kv_cache` | string | `auto` | One of `auto`, `off`, `on`. The engine has no KV cache yet, so `auto` and `off` are accepted no-ops; `kv_cache:on` fails the request until the prefix-KV cache lands upstream. |
+| `eb_max_steps` | integer | 48 | Maximum denoise steps per canvas. Blocks exit early once stable **and** confident, so this is a ceiling, not a fixed cost. Lower values are faster but can degrade quality. |
+| `eb_t_min` | float | 0.4 | Lower bound of the linear temperature schedule. |
+| `eb_t_max` | float | 0.8 | Upper bound of the linear temperature schedule: `t = t_min + (t_max - t_min) * cur_step/max_steps`, with `cur_step` counting down, so denoising anneals from `t_max` toward `t_min`. |
+| `eb_entropy_bound` | float | 0.1 | Per-step acceptance budget: canvas positions are sorted by entropy (ascending) and accepted while the cumulative entropy, minus the position's own, stays at or below the bound. Higher accepts more tokens per step (faster, riskier). |
+| `eb_stability_threshold` | integer | 1 | Consecutive identical argmax canvases required before a block counts as stable (`0` = always stable; at `1` the earliest exit is the 2nd identical step). |
+| `eb_confidence_threshold` | float | 0.005 | Mean-entropy ceiling for the "confident" half of the early-exit test; a block stops denoising only when it is both stable and below this. |
+
+Defaults for the `eb_*` knobs come from the GGUF's `diffusion.*` metadata when present, falling back to the engine defaults shown (DiffusionGemma's canonical values). The published `diffusiongemma-26B-A4B-it` GGUF carries only `diffusion.canvas_length`, so the fallbacks above are what you actually get.
+
+Per-request parameters: `max_tokens` maps to the engine's `n_predict` (omitted: engine default of 256), and a **positive** `seed` gives deterministic output (absent, zero or negative = a fresh random seed per call). Autoregressive sampling fields (`temperature`, `top_p`, `top_k`, ...) are **not used**: the EB sampler's own temperature schedule (`eb_t_min`/`eb_t_max`) replaces them.
+
+{{% notice note %}}
+
+**`max_tokens` rounds up to whole canvases.** The scheduler always commits whole canvases, so the token budget rounds **up** to `ceil(n_predict / canvas_length)` blocks and the completion may run slightly past the requested `max_tokens` (canonical DiffusionGemma behavior). Generation can still end earlier when the model emits an end-of-turn token, which finalizes the canvas.
+
+{{% /notice %}}
+
+#### Thinking
+
+DiffusionGemma's chat template makes thinking **opt-in** (the default render pre-closes an empty thought channel), so the backend defaults to thinking OFF - the opposite of most reasoning models. Enable it per request via the `metadata` field ([per-request override]({{%relref "advanced/model-configuration#per-request-override-via-metadata" %}})):
+
+```bash
+curl http://localhost:8080/v1/chat/completions \
+  -H "Content-Type: application/json" \
+  -d '{
+    "model": "diffusiongemma",
+    "messages": [{"role": "user", "content": "Explain quantum computing"}],
+    "metadata": {"enable_thinking": "true"}
+  }'
+```
+
+The model's thought channel then streams as `reasoning_content`, separate from the final `content`.
+
+#### Performance expectations
+
+Honest numbers from validation on a DGX Spark (GB10, CUDA 13, BF16 26B model, full GPU offload):
+
+- Engine load: ~33 s (50 GB of weights to GPU)
+- Forward pass: ~5.6 s per denoise step (256-token canvas); a block takes up to `eb_max_steps` steps but typically exits early (24/48 observed on a normal prompt, 4 steps on a trivial one)
+- End-to-end: ~0.15 tok/s at default settings, dominated by the per-step full recompute - this is the cost the upstream prefix-KV cache work targets
+
+On CPU the same forward step takes ~139 s (20 Grace cores): treat the CPU flavor as functional, not practical, for the 26B model.
+
+**Quantized models.** The Q4_K_M export (16.8 GB vs 50.5 GB BF16) was validated on the same GB10: it loads faster (~12.6 s vs ~32.7 s), quality held up in validation (golden-logits cosine 0.9862, coherent generation on the same prompt as the BF16 run, EB stopper exiting at 19/48 steps, ~0.49 tok/s on that run) - but a forward step takes ~27.5 s, about **5x slower than BF16** (~5.6 s/step) on this hardware. GB10-class GPUs run BF16 natively on tensor cores, while the K-quant MoE weights pay a dequantization cost on every denoise step. Choose Q4_K_M only when you are memory-bound; if BF16 fits, it is both faster and the file the engine's validation tolerances are calibrated for.
+
+#### Reference
+
+- [dllm.cpp](https://github.com/mudler/dllm.cpp)
+- [unsloth/diffusiongemma-26B-A4B-it-GGUF](https://huggingface.co/unsloth/diffusiongemma-26B-A4B-it-GGUF)
+
 ### vLLM
 
 [vLLM](https://github.com/vllm-project/vllm) is a fast and easy-to-use library for LLM inference.

gallery/diffusiongemma.yaml

@@ -0,0 +1,27 @@
+config_file: |
+    backend: dllm
+    known_usecases:
+        - chat
+    parameters:
+        # Forwarded to the engine as ctx_len, but the engine at the current
+        # pin ignores it - the effective bound is the GGUF's trained context
+        # (n_ctx_train, 262144 for this model). Kept for forward-compatibility
+        # once the engine honors it. Note dllm generates by denoising whole
+        # 256-token canvases, and until the prefix-KV cache lands (dllm P3)
+        # EVERY denoise step recomputes the full prompt+canvas, so throughput
+        # drops roughly linearly with context occupancy.
+        context_size: 4096
+    stopwords:
+        - <turn|>
+    # Templating AND output parsing (content/thought channels, tool calls)
+    # are owned by the dllm backend's native gemma4 renderer/parser - NOT
+    # llama.cpp's jinja autoparser, so no use_jinja option here.
+    # Disabling LocalAI's grammar keeps its generated tool grammar from
+    # overriding the backend's native tool-call pipeline (same reasoning as
+    # qwen3.yaml / the ds4 importer).
+    function:
+        grammar:
+            disable: true
+    template:
+        use_tokenizer_template: true
+name: diffusiongemma

gallery/index.yaml

@@ -1,4 +1,69 @@
 ---
+- name: "diffusiongemma-26b-a4b-it"
+  url: "github:mudler/LocalAI/gallery/diffusiongemma.yaml@master"
+  urls:
+    - https://huggingface.co/unsloth/diffusiongemma-26B-A4B-it-GGUF
+    - https://github.com/mudler/dllm.cpp
+  description: |
+    DiffusionGemma 26B A4B (instruction-tuned): Google DeepMind's experimental
+    block-diffusion language model, served by LocalAI's dllm backend
+    (dllm.cpp). Instead of autoregressive token-by-token decoding, text is
+    generated by iteratively denoising fixed 256-token canvases.
+
+    Honest expectations:
+    * Experimental: both the model family and the dllm backend are young -
+      expect rough edges.
+    * Q4_K_M weights (~17 GB): the memory-friendly default. Validated on
+      GB10 (quality holds: golden cosine 0.9862, coherent generation), but
+      note that on hardware with native BF16 tensor cores (GB10-class) the
+      BF16 file is ~5x FASTER per denoise step than K-quants - if ~50 GB
+      fits, fetch diffusiongemma-26B-A4B-it-BF16.gguf manually instead.
+    * Throughput: every denoise step currently recomputes the full
+      prompt+canvas - the prefix-KV cache that removes this lands with the
+      dllm backend's P3 work - so long prompts cost proportionally more per
+      generated block.
+    * Chat templating, thinking channels and tool calls are rendered and
+      parsed natively by the dllm backend (gemma4 renderer/parser), not by
+      llama.cpp's jinja autoparser.
+  license: apache-2.0
+  tags:
+    - llm
+    - gguf
+    - gemma
+    - diffusion
+    - dllm
+  overrides:
+    parameters:
+      model: dllm/diffusiongemma-26B-A4B-it-Q4_K_M.gguf
+  files:
+    - filename: dllm/diffusiongemma-26B-A4B-it-Q4_K_M.gguf
+      sha256: d2ca2c032ebfb23cf2d1794a3465e615c7545634d46b3c30652a26d8b07c4ad3
+      uri: https://huggingface.co/unsloth/diffusiongemma-26B-A4B-it-GGUF/resolve/main/diffusiongemma-26B-A4B-it-Q4_K_M.gguf
+- name: "diffusiongemma-26b-a4b-it-q8_0"
+  url: "github:mudler/LocalAI/gallery/diffusiongemma.yaml@master"
+  urls:
+    - https://huggingface.co/unsloth/diffusiongemma-26B-A4B-it-GGUF
+    - https://github.com/mudler/dllm.cpp
+  description: |
+    DiffusionGemma 26B A4B (instruction-tuned), Q8_0 quantization (~27 GB):
+    the higher-fidelity middle ground between Q4_K_M (~17 GB) and BF16
+    (~50 GB). Served by LocalAI's dllm backend (dllm.cpp); see the Q4_K_M
+    entry for the full notes on experimental status, throughput, and the
+    K-quant-vs-BF16 speed trade-off on BF16-native hardware.
+  license: apache-2.0
+  tags:
+    - llm
+    - gguf
+    - gemma
+    - diffusion
+    - dllm
+  overrides:
+    parameters:
+      model: dllm/diffusiongemma-26B-A4B-it-Q8_0.gguf
+  files:
+    - filename: dllm/diffusiongemma-26B-A4B-it-Q8_0.gguf
+      sha256: fa5180660b80d52aae94ed814a6183af303841d8bb425a27f13ea27400a7b430
+      uri: https://huggingface.co/unsloth/diffusiongemma-26B-A4B-it-GGUF/resolve/main/diffusiongemma-26B-A4B-it-Q8_0.gguf
 - name: "gemma-4-26b-a4b-it-qat"
   url: "github:mudler/LocalAI/gallery/virtual.yaml@master"
   urls:

pkg/grpc/cancel_test.go

@@ -0,0 +1,158 @@
+package grpc
+
+import (
+	"context"
+	"errors"
+	"sync"
+	"sync/atomic"
+	"time"
+
+	"github.com/mudler/LocalAI/pkg/grpc/base"
+	pb "github.com/mudler/LocalAI/pkg/grpc/proto"
+	. "github.com/onsi/ginkgo/v2"
+	. "github.com/onsi/gomega"
+)
+
+var errGenCancelled = errors.New("generation cancelled")
+
+// cancellableBackend implements AIModel + AIModelRich + Cancellable. Its
+// rich predict paths optionally block until Cancel fires (blockUntilCancel),
+// which lets the specs prove the server's context.AfterFunc plumbing: a
+// cancelled request context must reach Cancel and unblock the generation.
+type cancellableBackend struct {
+	base.SingleThread
+
+	blockUntilCancel bool
+
+	started     chan struct{} // closed when a predict call is in flight
+	startOnce   sync.Once
+	cancelled   chan struct{} // closed by Cancel
+	cancelOnce  sync.Once
+	cancelCalls atomic.Int32
+}
+
+func newCancellableBackend(blockUntilCancel bool) *cancellableBackend {
+	return &cancellableBackend{
+		blockUntilCancel: blockUntilCancel,
+		started:          make(chan struct{}),
+		cancelled:        make(chan struct{}),
+	}
+}
+
+func (c *cancellableBackend) Cancel() {
+	c.cancelCalls.Add(1)
+	c.cancelOnce.Do(func() { close(c.cancelled) })
+}
+
+func (c *cancellableBackend) run() error {
+	c.startOnce.Do(func() { close(c.started) })
+	if !c.blockUntilCancel {
+		return nil
+	}
+	select {
+	case <-c.cancelled:
+		return errGenCancelled
+	case <-time.After(30 * time.Second):
+		// Backstop so a regression (Cancel never wired) fails the spec
+		// instead of hanging the suite.
+		return errors.New("cancellableBackend: Cancel never fired")
+	}
+}
+
+func (c *cancellableBackend) PredictRich(*pb.PredictOptions) (*pb.Reply, error) {
+	if err := c.run(); err != nil {
+		return nil, err
+	}
+	return &pb.Reply{Message: []byte("done")}, nil
+}
+
+func (c *cancellableBackend) PredictStreamRich(_ *pb.PredictOptions, out chan<- *pb.Reply) error {
+	out <- &pb.Reply{Message: []byte("first")}
+	return c.run()
+}
+
+func (c *cancellableBackend) Predict(*pb.PredictOptions) (string, error) {
+	return "", errors.New("cancellableBackend: legacy Predict should not have been called")
+}
+
+func (c *cancellableBackend) PredictStream(*pb.PredictOptions, chan string) error {
+	return errors.New("cancellableBackend: legacy PredictStream should not have been called")
+}
+
+var _ AIModelRich = (*cancellableBackend)(nil)
+var _ Cancellable = (*cancellableBackend)(nil)
+
+var _ = Describe("Cancellable capability", func() {
+	It("PredictStream: cancelling the request context fires Cancel and ends the stream with the backend's error", func() {
+		backend := newCancellableBackend(true)
+		addr := "test://cancel-stream"
+		Provide(addr, backend)
+		c := NewClient(addr, true, nil, false)
+
+		ctx, cancel := context.WithCancel(context.Background())
+		defer cancel()
+
+		errCh := make(chan error, 1)
+		go func() {
+			defer GinkgoRecover()
+			errCh <- c.PredictStream(ctx, &pb.PredictOptions{}, func(*pb.Reply) {})
+		}()
+
+		// Only cancel once the generation is provably in flight; cancelling
+		// earlier would race the AfterFunc registration in the server.
+		Eventually(backend.started, "5s").Should(BeClosed())
+		cancel()
+
+		var err error
+		Eventually(errCh, "5s").Should(Receive(&err))
+		Expect(err).To(MatchError(errGenCancelled))
+		Expect(backend.cancelCalls.Load()).To(BeNumerically(">=", 1))
+	})
+
+	It("Predict: cancelling the request context fires Cancel and unblocks the call", func() {
+		backend := newCancellableBackend(true)
+		addr := "test://cancel-predict"
+		Provide(addr, backend)
+		c := NewClient(addr, true, nil, false)
+
+		ctx, cancel := context.WithCancel(context.Background())
+		defer cancel()
+
+		errCh := make(chan error, 1)
+		go func() {
+			defer GinkgoRecover()
+			_, err := c.Predict(ctx, &pb.PredictOptions{})
+			errCh <- err
+		}()
+
+		Eventually(backend.started, "5s").Should(BeClosed())
+		cancel()
+
+		var err error
+		Eventually(errCh, "5s").Should(Receive(&err))
+		Expect(err).To(MatchError(errGenCancelled))
+		Expect(backend.cancelCalls.Load()).To(BeNumerically(">=", 1))
+	})
+
+	It("does not call Cancel when the request completes normally", func() {
+		backend := newCancellableBackend(false)
+		addr := "test://cancel-clean"
+		Provide(addr, backend)
+		c := NewClient(addr, true, nil, false)
+
+		ctx, cancel := context.WithCancel(context.Background())
+
+		var replies []*pb.Reply
+		err := c.PredictStream(ctx, &pb.PredictOptions{}, func(r *pb.Reply) {
+			replies = append(replies, r)
+		})
+		Expect(err).ToNot(HaveOccurred())
+		Expect(replies).To(HaveLen(1))
+
+		// Cancelling AFTER completion must not reach the backend: the
+		// deferred AfterFunc stop de-registered the hook, so a shared or
+		// reused context cannot abort someone else's later generation.
+		cancel()
+		Consistently(backend.cancelCalls.Load, "200ms").Should(BeZero())
+	})
+})

pkg/grpc/interface.go

@@ -72,6 +72,19 @@ func newReply(s string) *pb.Reply {
 	return &pb.Reply{Message: []byte(s)}
 }
 
+// Cancellable is an optional capability: backends that can abort an
+// in-flight generation implement it. The server calls Cancel when the
+// request's gRPC context is cancelled (client disconnect/timeout),
+// giving Go backends the same semantics the llama.cpp C++ backend gets
+// from polling context->IsCancelled() in its result loops.
+//
+// Cancel may be invoked from an arbitrary goroutine while the
+// generation is running, so implementations must make it safe to call
+// concurrently with Predict/PredictStream (and their rich variants).
+type Cancellable interface {
+	Cancel()
+}
+
 // AIModelRich is an optional extension to AIModel for backends that
 // can produce a full *pb.Reply — including tool-call deltas and
 // usage tokens — rather than just a content string. The gRPC server

pkg/grpc/server.go

@@ -63,11 +63,32 @@ func (s *server) LoadModel(ctx context.Context, in *pb.ModelOptions) (*pb.Result
 	return &pb.Result{Message: "Loading succeeded", Success: true}, nil
 }
 
+// cancelOnDone arms the optional Cancellable capability: when ctx is
+// cancelled (client disconnect/timeout) the backend's Cancel fires so it
+// can abort the in-flight generation - the Go-backend equivalent of the
+// llama.cpp C++ server polling context->IsCancelled() in its result loops.
+// Callers MUST defer the returned stop so a normally-completed request
+// de-registers the hook before returning; otherwise a later cancellation
+// of the same ctx would abort an unrelated in-flight generation.
+//
+// Arm it AFTER the Locking() block: for serialized backends a request
+// queued on the lock is not generating yet, and cancelling it must not
+// abort whichever request currently owns the backend.
+func (s *server) cancelOnDone(ctx context.Context) (stop func() bool) {
+	if c, ok := s.llm.(Cancellable); ok {
+		return context.AfterFunc(ctx, c.Cancel)
+	}
+	return func() bool { return false }
+}
+
 func (s *server) Predict(ctx context.Context, in *pb.PredictOptions) (*pb.Reply, error) {
 	if s.llm.Locking() {
 		s.llm.Lock()
 		defer s.llm.Unlock()
 	}
+	// One registration covers both the rich and the legacy branch below.
+	stop := s.cancelOnDone(ctx)
+	defer stop()
 	if rich, ok := s.llm.(AIModelRich); ok {
 		return rich.PredictRich(in)
 	}
@@ -275,6 +296,10 @@ func (s *server) PredictStream(in *pb.PredictOptions, stream pb.Backend_PredictS
 		defer s.llm.Unlock()
 	}
 
+	// One registration covers both the rich and the legacy branch below.
+	stop := s.cancelOnDone(stream.Context())
+	defer stop()
+
 	if rich, ok := s.llm.(AIModelRich); ok {
 		replyChan := make(chan *pb.Reply)
 		done := make(chan bool)

tests/e2e-backends/backend_test.go

@@ -66,6 +66,12 @@ import (
 //	BACKEND_TEST_IMAGE_STEPS Override the diffusion step count for the image spec
 //	                         (default: 4 — keeps CPU-only runs under a few minutes).
 //	BACKEND_TEST_PROMPT      Override the prompt used by predict/stream specs.
+//	BACKEND_TEST_SEED        Optional sampling seed (>0) passed to the predict
+//	                         and stream specs. Unset keeps backend-default
+//	                         randomness. Needed for random-weight fixture
+//	                         models (e.g. dllm's tiny_with_vocab.gguf) where
+//	                         unseeded sampling makes the output - and thus the
+//	                         spec outcome - nondeterministic.
 //	BACKEND_TEST_CTX_SIZE    Override the context size passed to LoadModel (default 512).
 //	BACKEND_TEST_THREADS     Override Threads passed to LoadModel (default 4).
 //	BACKEND_TEST_OPTIONS     Comma-separated Options[] entries passed to LoadModel,
@@ -419,6 +425,7 @@ var _ = Describe("Backend container", Ordered, func() {
 			Temperature: 0.1,
 			TopK:        40,
 			TopP:        0.9,
+			Seed:        envInt32("BACKEND_TEST_SEED", 0),
 		})
 		Expect(err).NotTo(HaveOccurred())
 		Expect(res.GetMessage()).NotTo(BeEmpty(), "Predict produced empty output")
@@ -438,6 +445,7 @@ var _ = Describe("Backend container", Ordered, func() {
 			Temperature: 0.1,
 			TopK:        40,
 			TopP:        0.9,
+			Seed:        envInt32("BACKEND_TEST_SEED", 0),
 		})
 		Expect(err).NotTo(HaveOccurred())
 

tests/e2e-backends/dllm_test.go

@@ -0,0 +1,302 @@
+package e2ebackends_test
+
+import (
+	"context"
+	"fmt"
+	"io"
+	"net"
+	"os"
+	"os/exec"
+	"path/filepath"
+	"time"
+
+	pb "github.com/mudler/LocalAI/pkg/grpc/proto"
+	. "github.com/onsi/ginkgo/v2"
+	. "github.com/onsi/gomega"
+	"github.com/phayes/freeport"
+	"google.golang.org/grpc"
+	"google.golang.org/grpc/credentials/insecure"
+)
+
+// ─── dllm templated chat-completion e2e (opt-in, BACKEND_BINARY mode) ────────
+//
+// The generic "Backend container" suite already exercises dllm's
+// health/load/predict/stream surface in BACKEND_BINARY mode (ds4 precedent:
+// hardware-gated backends skip the Docker image and point BACKEND_BINARY at a
+// packaged run.sh). What it does NOT cover is the templated chat path: dllm
+// owns prompt rendering AND output parsing natively (the gemma4
+// renderer/parser, not llama.cpp's jinja autoparser), and that path only
+// triggers when PredictOptions carries Messages + UseTokenizerTemplate.
+// These specs drive exactly that round trip over the real gRPC server
+// binary, non-streaming and streaming.
+//
+// Tiny-model spec (cheap, runs anywhere a libdllm.so build exists):
+//
+//	BACKEND_TEST_DLLM=1       enables the spec (skipped by default, CI-safe)
+//	BACKEND_BINARY            packaged dllm run.sh (backend/go/dllm/run.sh with
+//	                          dllm-grpc + libdllm.so next to it, or
+//	                          package/run.sh from 'make -C backend/go/dllm package')
+//	BACKEND_TEST_MODEL_FILE   dllm.cpp's tests/fixtures/tiny_with_vocab.gguf
+//	                          (random weights + handcrafted 43-token gemma4 vocab)
+//
+// Real-model spec (the 26B BF16 GGUF, ~50 GB; CUDA-13-class hardware):
+//
+//	BACKEND_TEST_DLLM_REAL_MODEL_FILE  path to diffusiongemma-26B-A4B-it-BF16.gguf;
+//	                                   setting it enables the spec (skipped by
+//	                                   default; BACKEND_BINARY still required)
+//	BACKEND_TEST_DLLM_REAL_GPU_LAYERS  NGPULayers for the real model
+//	                                   (default -1 = full offload)
+//
+// Tool-call e2e is deliberately absent: the tiny fixture has RANDOM weights,
+// so it cannot be prompted into emitting gemma4 <|tool_call> markup and a
+// live tool-call assertion would be flaky-by-construction. Tool-call
+// rendering and parsing are pinned by unit tables in backend/go/dllm
+// (gemma4_renderer_test.go / gemma4_parser_test.go) instead; the real-model
+// spec can grow a tools cap once a quantized checkpoint is cheap enough to
+// gate on.
+
+// startDllmBackend boots the packaged dllm backend via BACKEND_BINARY's
+// run.sh, waits for the gRPC port, loads modelFile, and returns a connected
+// client. Fails the spec on any error. Teardown is registered with
+// DeferCleanup the moment each resource exists, so a failure anywhere in
+// setup (port-wait timeout, dial error, LoadModel failure) still reaps the
+// spawned server - critical for the real-model spec, where a failed load
+// would otherwise leak a ~50GB process. options are extra ModelOptions
+// "key:value" entries (eb_* sampler knobs etc.).
+func startDllmBackend(modelFile string, gpuLayers int32, options ...string) pb.BackendClient {
+	GinkgoHelper()
+
+	binary := os.Getenv("BACKEND_BINARY")
+	Expect(binary).NotTo(BeEmpty(),
+		"dllm chat spec requires BACKEND_BINARY pointing at the packaged dllm run.sh")
+	Expect(filepath.Base(binary)).To(Equal("run.sh"),
+		"BACKEND_BINARY must point at a run.sh (see backend/go/dllm/package.sh)")
+	binaryDir := filepath.Dir(binary)
+	Expect(filepath.Join(binaryDir, "run.sh")).To(BeAnExistingFile())
+	Expect(modelFile).To(BeAnExistingFile())
+
+	port, err := freeport.GetFreePort()
+	Expect(err).NotTo(HaveOccurred())
+	addr := fmt.Sprintf("127.0.0.1:%d", port)
+
+	Expect(os.Chmod(filepath.Join(binaryDir, "run.sh"), 0o755)).To(Succeed())
+	cmd := exec.Command(filepath.Join(binaryDir, "run.sh"), "--addr="+addr)
+	cmd.Stdout = GinkgoWriter
+	cmd.Stderr = GinkgoWriter
+	Expect(cmd.Start()).To(Succeed())
+	DeferCleanup(func() {
+		_ = cmd.Process.Kill()
+		_, _ = cmd.Process.Wait()
+	})
+
+	Eventually(func() error {
+		c, derr := net.DialTimeout("tcp", addr, 500*time.Millisecond)
+		if derr != nil {
+			return derr
+		}
+		_ = c.Close()
+		return nil
+	}, 30*time.Second, 200*time.Millisecond).Should(Succeed(), "dllm backend did not start")
+
+	conn, err := grpc.Dial(addr,
+		grpc.WithTransportCredentials(insecure.NewCredentials()),
+		grpc.WithDefaultCallOptions(grpc.MaxCallRecvMsgSize(50*1024*1024)),
+	)
+	Expect(err).NotTo(HaveOccurred())
+	DeferCleanup(func() {
+		_ = conn.Close()
+	})
+	client := pb.NewBackendClient(conn)
+
+	// 15 min: reading the 26B BF16 from a cold disk dominates real-model load.
+	ctx, cancel := context.WithTimeout(context.Background(), 15*time.Minute)
+	defer cancel()
+	res, err := client.LoadModel(ctx, &pb.ModelOptions{
+		Model:       modelFile,
+		ModelFile:   modelFile,
+		ContextSize: envInt32("BACKEND_TEST_CTX_SIZE", 512),
+		Threads:     envInt32("BACKEND_TEST_THREADS", 4),
+		NGPULayers:  gpuLayers,
+		Options:     options,
+	})
+	Expect(err).NotTo(HaveOccurred())
+	Expect(res.GetSuccess()).To(BeTrue(), "dllm LoadModel failed: %s", res.GetMessage())
+
+	return client
+}
+
+// dllmChatRequest builds the templated chat request shared by both specs.
+// The user content is fixed to "hello": the tiny fixture's handcrafted
+// 43-token vocab is guaranteed to cover it (and the gemma4 template markup),
+// while arbitrary English text is not tokenizable by that vocab.
+func dllmChatRequest() *pb.PredictOptions {
+	return &pb.PredictOptions{
+		Messages:             []*pb.Message{{Role: "user", Content: "hello"}},
+		UseTokenizerTemplate: true,
+		// Rounds up to one whole 256-token canvas (dllm commits whole
+		// canvases); keeps the tiny run fast and the real run bounded.
+		Tokens:      16,
+		Temperature: 0.1,
+		Seed:        7,
+	}
+}
+
+// assertDllmChat does the non-streaming templated round trip: no error,
+// non-empty content, parsed ChatDeltas present.
+func assertDllmChat(client pb.BackendClient) {
+	GinkgoHelper()
+	ctx, cancel := context.WithTimeout(context.Background(), 20*time.Minute)
+	defer cancel()
+	res, err := client.Predict(ctx, dllmChatRequest())
+	Expect(err).NotTo(HaveOccurred())
+	Expect(string(res.GetMessage())).NotTo(BeEmpty(), "templated chat completion produced empty content")
+	Expect(res.GetChatDeltas()).NotTo(BeEmpty(), "templated chat completion produced no ChatDeltas")
+	GinkgoWriter.Printf("dllm chat: %q (deltas=%d)\n", string(res.GetMessage()), len(res.GetChatDeltas()))
+}
+
+// assertDllmChatStream does the streaming variant: >=1 chunk, non-empty
+// combined content.
+func assertDllmChatStream(client pb.BackendClient) {
+	GinkgoHelper()
+	ctx, cancel := context.WithTimeout(context.Background(), 20*time.Minute)
+	defer cancel()
+	stream, err := client.PredictStream(ctx, dllmChatRequest())
+	Expect(err).NotTo(HaveOccurred())
+
+	var chunks int
+	var combined string
+	for {
+		msg, rerr := stream.Recv()
+		if rerr == io.EOF {
+			break
+		}
+		Expect(rerr).NotTo(HaveOccurred())
+		if len(msg.GetMessage()) > 0 {
+			chunks++
+			combined += string(msg.GetMessage())
+		}
+	}
+	Expect(chunks).To(BeNumerically(">=", 1), "no stream chunks received")
+	Expect(combined).NotTo(BeEmpty(), "streamed chat completion produced empty content")
+	GinkgoWriter.Printf("dllm chat stream: %d chunks, combined=%q\n", chunks, combined)
+}
+
+var _ = Describe("dllm templated chat-completion (tiny model)", Ordered, func() {
+	var client pb.BackendClient
+
+	BeforeAll(func() {
+		if os.Getenv("BACKEND_TEST_DLLM") != "1" {
+			Skip("dllm chat spec is opt-in; set BACKEND_TEST_DLLM=1 (plus BACKEND_BINARY and BACKEND_TEST_MODEL_FILE) to run it")
+		}
+		modelFile := os.Getenv("BACKEND_TEST_MODEL_FILE")
+		Expect(modelFile).NotTo(BeEmpty(),
+			"dllm chat spec requires BACKEND_TEST_MODEL_FILE (dllm.cpp's tests/fixtures/tiny_with_vocab.gguf)")
+		client = startDllmBackend(modelFile, 0)
+	})
+
+	It("answers a templated chat completion", func() {
+		assertDllmChat(client)
+	})
+
+	It("streams a templated chat completion", func() {
+		assertDllmChatStream(client)
+	})
+})
+
+var _ = Describe("dllm request cancellation (tiny model)", Ordered, func() {
+	var client pb.BackendClient
+
+	BeforeAll(func() {
+		if os.Getenv("BACKEND_TEST_DLLM") != "1" {
+			Skip("dllm cancellation spec is opt-in; set BACKEND_TEST_DLLM=1 (plus BACKEND_BINARY and BACKEND_TEST_MODEL_FILE) to run it")
+		}
+		modelFile := os.Getenv("BACKEND_TEST_MODEL_FILE")
+		Expect(modelFile).NotTo(BeEmpty(),
+			"dllm cancellation spec requires BACKEND_TEST_MODEL_FILE (dllm.cpp's tests/fixtures/tiny_with_vocab.gguf)")
+		// eb_max_steps inflates the per-block denoise loop: a 256-token run
+		// takes ~10s on the tiny fixture (vs ~40ms at engine defaults), so a
+		// cancelled request is clearly distinguishable from one that simply
+		// finished. A dedicated backend process keeps the chat specs fast.
+		client = startDllmBackend(modelFile, 0, "eb_max_steps:256")
+	})
+
+	// This is the end-to-end proof of the Cancellable plumbing
+	// (pkg/grpc/server.go arming backend.Cancel via context.AfterFunc on
+	// the stream context): a client disconnect mid-stream must abort the
+	// server-side generation, not just orphan it.
+	It("aborts the in-flight generation when the client context is cancelled mid-stream", func() {
+		ctx, cancel := context.WithCancel(context.Background())
+		defer cancel()
+		// Raw-prompt mode, not the templated chat request: the templated
+		// render can hit an end-of-turn token after the first block and
+		// finish before the cancel lands, which would silently turn this
+		// into a no-op spec. The raw "hello" run is probed deterministic
+		// with seed 7: 16 blocks, the eb_max_steps cap hit on every one,
+		// ~10s total if left to finish.
+		req := &pb.PredictOptions{Prompt: "hello", Tokens: 256, Seed: 7}
+
+		stream, err := client.PredictStream(ctx, req)
+		Expect(err).NotTo(HaveOccurred())
+
+		// First chunk received = the generate is provably in flight (the C
+		// side resets the cancel flag on generate entry, so cancelling
+		// before it starts would be swallowed).
+		_, err = stream.Recv()
+		Expect(err).NotTo(HaveOccurred())
+		cancel()
+
+		// Client side: the stream must end promptly, not after the
+		// remaining ~9s of generation (the first chunk arrives after one
+		// ~0.7s block, so plenty of generation is provably outstanding).
+		recvDone := make(chan error, 1)
+		go func() {
+			defer GinkgoRecover()
+			for {
+				if _, rerr := stream.Recv(); rerr != nil {
+					recvDone <- rerr
+					return
+				}
+			}
+		}()
+		var rerr error
+		Eventually(recvDone, "5s").Should(Receive(&rerr))
+		Expect(rerr).NotTo(Equal(io.EOF), "stream completed normally despite the cancelled context")
+
+		// Server side: prove the generation actually aborted. dllm
+		// serializes every C call through one worker goroutine, so if the
+		// orphaned generation were still grinding, this follow-up would
+		// queue behind its remaining ~9s instead of completing in ~1s
+		// (16 tokens = one block at eb_max_steps:256).
+		followCtx, followCancel := context.WithTimeout(context.Background(), 2*time.Minute)
+		defer followCancel()
+		start := time.Now()
+		res, err := client.Predict(followCtx, dllmChatRequest())
+		elapsed := time.Since(start)
+		Expect(err).NotTo(HaveOccurred())
+		Expect(string(res.GetMessage())).NotTo(BeEmpty())
+		Expect(elapsed).To(BeNumerically("<", 5*time.Second),
+			"follow-up request queued behind the cancelled generation - server-side Cancel did not reach the backend")
+		GinkgoWriter.Printf("dllm cancel e2e: follow-up completed in %v after mid-stream cancellation\n", elapsed)
+	})
+})
+
+var _ = Describe("dllm templated chat-completion (real model)", Ordered, func() {
+	var client pb.BackendClient
+
+	BeforeAll(func() {
+		modelFile := os.Getenv("BACKEND_TEST_DLLM_REAL_MODEL_FILE")
+		if modelFile == "" {
+			Skip("real-model dllm spec is opt-in; set BACKEND_TEST_DLLM_REAL_MODEL_FILE (the 26B BF16 GGUF) to run it")
+		}
+		client = startDllmBackend(modelFile,
+			envInt32("BACKEND_TEST_DLLM_REAL_GPU_LAYERS", -1))
+	})
+
+	It("answers a templated chat completion", func() {
+		assertDllmChat(client)
+	})
+
+	It("streams a templated chat completion", func() {
+		assertDllmChatStream(client)
+	})
+})