diff --git a/backend/cpp/buun-llama-cpp/Makefile b/backend/cpp/buun-llama-cpp/Makefile
index 2a18bf41c..07e7335ad 100644
--- a/backend/cpp/buun-llama-cpp/Makefile
+++ b/backend/cpp/buun-llama-cpp/Makefile
@@ -50,6 +50,7 @@ define buun-llama-cpp-build
 	# *copy*, never the original under backend/cpp/llama-cpp/, so the stock
 	# llama-cpp build stays compiling against vanilla upstream.
 	bash $(CURRENT_MAKEFILE_DIR)/patch-grpc-server.sh $(CURRENT_MAKEFILE_DIR)/../buun-llama-cpp-$(1)-build/grpc-server.cpp
+	bash $(LLAMA_CPP_DIR)/disable-score-task.sh $(CURRENT_MAKEFILE_DIR)/../buun-llama-cpp-$(1)-build/grpc-server.cpp
 	$(info $(GREEN)I buun-llama-cpp build info:$(1)$(RESET))
 	LLAMA_REPO=$(LLAMA_REPO) LLAMA_VERSION=$(BUUN_LLAMA_VERSION) \
 	$(MAKE) -C $(CURRENT_MAKEFILE_DIR)/../buun-llama-cpp-$(1)-build llama.cpp
@@ -81,6 +82,9 @@ buun-llama-cpp-rpc-server: buun-llama-cpp-grpc
 package:
 	bash package.sh
 
+test:
+	bash test-patch-grpc-server.sh
+
 purge:
 	rm -rf $(CURRENT_MAKEFILE_DIR)/../buun-llama-cpp-*-build
 	rm -rf buun-llama-cpp-* package
diff --git a/backend/cpp/buun-llama-cpp/patch-grpc-server.sh b/backend/cpp/buun-llama-cpp/patch-grpc-server.sh
index f753b179a..42f35a343 100755
--- a/backend/cpp/buun-llama-cpp/patch-grpc-server.sh
+++ b/backend/cpp/buun-llama-cpp/patch-grpc-server.sh
@@ -6,8 +6,9 @@
 #      fork-specific `turbo2` / `turbo3` / `turbo4` cache types plus the buun
 #      additions `turbo2_tcq` / `turbo3_tcq`.
 #
-#   2. Wire up buun-exclusive speculative-decoding option handlers
-#      (tree_budget / draft_topk) alongside the existing spec_* handlers.
+#   2. Adapt the post-refactor speculative-decoding fields and option handlers
+#      to the fork's legacy flat common_params_speculative layout, while adding
+#      buun-exclusive tree_budget / draft_topk support.
 #      These reference struct fields (common_params.speculative.tree_budget
 #      and .draft_topk) that only exist in buun's common/common.h — adding
 #      them to the shared backend/cpp/llama-cpp/grpc-server.cpp would break
@@ -76,53 +77,86 @@ else
     echo "==> KV allow-list patch OK"
 fi
 
-if grep -q 'optname, "tree_budget"' "$SRC"; then
-    echo "==> $SRC already has DFlash option handlers, skipping"
+if grep -q 'buun-llama-cpp legacy speculative options' "$SRC"; then
+    echo "==> $SRC already has legacy speculative option handlers, skipping"
 else
-    echo "==> patching $SRC to add tree_budget / draft_topk option handlers"
+    echo "==> replacing modern speculative option handlers with the fork-compatible set"
 
-    # Insert two new `else if` handlers between the inner close-brace of the
-    # `spec_p_split` block and the next `} else if (…spec_ngram_size_n…)` line.
-    # Upstream writes each `} else if` as a single physical line, so we don't
-    # emit an outer `}` ourselves — the existing next line provides both the
-    # close of our `draft_topk` block and the open of `spec_ngram_size_n`.
-    # Anchor on the exact 3-line body of spec_p_split so we can't drift.
+    # Replace the whole speculative option section. The fork predates chained
+    # speculative types and the nested draft/ngram families, so retaining any
+    # modern-only handler makes the copied server fail at compile time.
     awk '
-        prev2 == "        } else if (!strcmp(optname, \"spec_p_split\")) {" &&
-        prev1 ~ /^ +if \(optval != NULL\) \{$/ &&
-        $0    ~ /^ +try \{ params\.speculative\.draft\.p_split = std::stof\(optval_str\); \} catch \(\.\.\.\) \{\}$/ &&
-        !done {
-            print                        # print the try-line itself
-            getline inner_close          # read "            }" closing the inner if
-            print inner_close            # print it — this closes spec_p_split body
-            print "        // buun-llama-cpp DFlash options — added by patch-grpc-server.sh"
+        /} else if \(!strcmp\(optname, "spec_type"\)/ && !done {
+            print "        // buun-llama-cpp legacy speculative options"
+            print "        } else if (!strcmp(optname, \"spec_type\") || !strcmp(optname, \"speculative_type\")) {"
+            print "            auto type = common_speculative_type_from_name(optval_str.substr(0, optval_str.find(\",\")));"
+            print "            if (type != COMMON_SPECULATIVE_TYPE_COUNT) params.speculative.type = type;"
+            print "        } else if (!strcmp(optname, \"spec_n_max\") || !strcmp(optname, \"draft_max\")) {"
+            print "            if (optval != NULL) { try { params.speculative.n_max = std::stoi(optval_str); } catch (...) {} }"
+            print "        } else if (!strcmp(optname, \"spec_n_min\") || !strcmp(optname, \"draft_min\")) {"
+            print "            if (optval != NULL) { try { params.speculative.n_min = std::stoi(optval_str); } catch (...) {} }"
+            print "        } else if (!strcmp(optname, \"spec_p_min\") || !strcmp(optname, \"draft_p_min\")) {"
+            print "            if (optval != NULL) { try { params.speculative.p_min = std::stof(optval_str); } catch (...) {} }"
+            print "        } else if (!strcmp(optname, \"spec_p_split\")) {"
+            print "            if (optval != NULL) { try { params.speculative.p_split = std::stof(optval_str); } catch (...) {} }"
+            print "        } else if (!strcmp(optname, \"spec_ngram_size_n\") || !strcmp(optname, \"ngram_size_n\")) {"
+            print "            if (optval != NULL) { try { params.speculative.ngram_size_n = (uint16_t)std::stoi(optval_str); } catch (...) {} }"
+            print "        } else if (!strcmp(optname, \"spec_ngram_size_m\") || !strcmp(optname, \"ngram_size_m\")) {"
+            print "            if (optval != NULL) { try { params.speculative.ngram_size_m = (uint16_t)std::stoi(optval_str); } catch (...) {} }"
+            print "        } else if (!strcmp(optname, \"spec_ngram_min_hits\") || !strcmp(optname, \"ngram_min_hits\")) {"
+            print "            if (optval != NULL) { try { params.speculative.ngram_min_hits = (uint16_t)std::stoi(optval_str); } catch (...) {} }"
+            print "        } else if (!strcmp(optname, \"draft_gpu_layers\")) {"
+            print "            if (optval != NULL) { try { params.speculative.n_gpu_layers = std::stoi(optval_str); } catch (...) {} }"
             print "        } else if (!strcmp(optname, \"tree_budget\")) {"
-            print "            if (optval != NULL) {"
-            print "                try { params.speculative.tree_budget = std::stoi(optval_str); } catch (...) {}"
-            print "            }"
+            print "            if (optval != NULL) { try { params.speculative.tree_budget = std::stoi(optval_str); } catch (...) {} }"
             print "        } else if (!strcmp(optname, \"draft_topk\")) {"
-            print "            if (optval != NULL) {"
-            print "                try { params.speculative.draft_topk = std::stoi(optval_str); } catch (...) {}"
-            print "            }"
-            # The next source line (`} else if (…spec_ngram_size_n…) {`) closes
-            # our draft_topk block and continues the chain naturally; fall back
-            # into the main loop to emit it and everything after.
-            done = 1
-            prev2 = prev1
-            prev1 = inner_close
+            print "            if (optval != NULL) { try { params.speculative.draft_topk = std::stoi(optval_str); } catch (...) {} }"
+            skipping = 1
             next
         }
-        { print; prev2 = prev1; prev1 = $0 }
+        skipping && /^    }$/ { skipping = 0; done = 1; print; next }
+        !skipping { print }
         END {
             if (!done) {
-                print "patch-grpc-server.sh: spec_p_split anchor not found" > "/dev/stderr"
+                print "patch-grpc-server.sh: speculative option section not found" > "/dev/stderr"
                 exit 1
             }
         }
     ' "$SRC" > "$SRC.tmp"
     mv "$SRC.tmp" "$SRC"
 
-    echo "==> DFlash option-handler patch OK"
+    echo "==> legacy speculative option-handler patch OK"
+fi
+
+# The modern server initializes a vector of speculative types when DraftModel
+# is present. The fork still exposes a single enum value.
+awk '
+    /const bool no_spec_type = params\.speculative\.types\.empty\(\)/ && !done {
+        print "        if (params.speculative.type == COMMON_SPECULATIVE_TYPE_NONE) {"
+        print "            params.speculative.type = COMMON_SPECULATIVE_TYPE_DRAFT;"
+        print "        }"
+        skipping = 1
+        next
+    }
+    skipping && /^        }$/ { skipping = 0; done = 1; next }
+    !skipping { print }
+' "$SRC" > "$SRC.tmp"
+mv "$SRC.tmp" "$SRC"
+
+# Map supported post-refactor fields back to the names used by the pinned fork.
+sed -E \
+    -e 's/params\.speculative\.draft\.mparams\.path/params.speculative.mparams_dft.path/g' \
+    -e 's/params\.speculative\.draft\.n_gpu_layers/params.speculative.n_gpu_layers/g' \
+    -e 's/ctx_server\.impl->model_tgt/ctx_server.impl->model/g' \
+    -e '/params\.cache_idle_slots =/d' \
+    -e '/params\.split_mode = LLAMA_SPLIT_MODE_TENSOR;/d' \
+    -e '/params\.speculative\.draft\.tensor_buft_overrides/d' \
+    "$SRC" > "$SRC.tmp"
+mv "$SRC.tmp" "$SRC"
+
+if ! grep -q '^#define LOCALAI_TURBOQUANT_NO_CHECKPOINT_MIN_STEP' "$SRC"; then
+    sed '0,/^#include/{s/^#include/#define LOCALAI_TURBOQUANT_NO_CHECKPOINT_MIN_STEP 1\n\n#include/}' "$SRC" > "$SRC.tmp"
+    mv "$SRC.tmp" "$SRC"
 fi
 
 if grep -qE 'ctx_server\.get_meta\(\)\.logit_bias_eog|params_base\.sampling\.logit_bias_eog,' "$SRC"; then
diff --git a/backend/cpp/buun-llama-cpp/test-patch-grpc-server.sh b/backend/cpp/buun-llama-cpp/test-patch-grpc-server.sh
new file mode 100755
index 000000000..03c8e774f
--- /dev/null
+++ b/backend/cpp/buun-llama-cpp/test-patch-grpc-server.sh
@@ -0,0 +1,34 @@
+#!/bin/bash
+
+set -euo pipefail
+
+SCRIPT_DIR=$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)
+SOURCE="$SCRIPT_DIR/../llama-cpp/grpc-server.cpp"
+TMP_DIR=$(mktemp -d)
+trap 'rm -rf "$TMP_DIR"' EXIT
+
+cp "$SOURCE" "$TMP_DIR/grpc-server.cpp"
+bash "$SCRIPT_DIR/patch-grpc-server.sh" "$TMP_DIR/grpc-server.cpp"
+bash "$SCRIPT_DIR/../llama-cpp/disable-score-task.sh" "$TMP_DIR/grpc-server.cpp"
+bash "$SCRIPT_DIR/patch-grpc-server.sh" "$TMP_DIR/grpc-server.cpp"
+
+for unsupported in \
+    'params.cache_idle_slots' \
+    'params.speculative.types' \
+    'params.speculative.draft.' \
+    'common_speculative_types_from_names' \
+    'COMMON_SPECULATIVE_TYPE_DRAFT_SIMPLE' \
+    'ctx_server.impl->model_tgt'; do
+    if grep -Fq "$unsupported" "$TMP_DIR/grpc-server.cpp"; then
+        echo "unsupported buun API remains: $unsupported" >&2
+        exit 1
+    fi
+done
+
+grep -Fq '#define LOCALAI_LLAMA_CPP_NO_SCORE_TASK 1' "$TMP_DIR/grpc-server.cpp"
+grep -Fq '#define LOCALAI_TURBOQUANT_NO_CHECKPOINT_MIN_STEP 1' "$TMP_DIR/grpc-server.cpp"
+grep -Fq 'params.speculative.mparams_dft.path = request->draftmodel();' "$TMP_DIR/grpc-server.cpp"
+grep -Fq 'params.speculative.type = COMMON_SPECULATIVE_TYPE_DRAFT;' "$TMP_DIR/grpc-server.cpp"
+grep -Fq 'ctx_server.impl->model' "$TMP_DIR/grpc-server.cpp"
+
+echo "buun grpc-server compatibility transform passed"