test(plugins): add lyrics capability integration test with test plugin

Refactor the lyrics system from a static function to an interface-based
service that supports WASM plugin providers. Plugins listed in the
LyricsPriority config (alongside "embedded" and file extensions) are
now resolved through the plugin system.

Includes capability definition, Go/Rust PDK, adapter, Wire integration,
and tests for plugin fallback behavior.

cmd/wire_gen.go

@@ -1,6 +1,6 @@
 // Code generated by Wire. DO NOT EDIT.
 
-//go:generate go run -mod=mod github.com/google/wire/cmd/wire gen -tags "netgo"
+//go:generate go run -mod=mod github.com/google/wire/cmd/wire gen -tags "netgo sqlite_fts5"
 //go:build !wireinject
 // +build !wireinject
 
@@ -16,6 +16,7 @@ import (
 	"github.com/navidrome/navidrome/core/artwork"
 	"github.com/navidrome/navidrome/core/external"
 	"github.com/navidrome/navidrome/core/ffmpeg"
+	"github.com/navidrome/navidrome/core/lyrics"
 	"github.com/navidrome/navidrome/core/metrics"
 	"github.com/navidrome/navidrome/core/playback"
 	"github.com/navidrome/navidrome/core/playlists"
@@ -103,7 +104,8 @@ func CreateSubsonicAPIRouter(ctx context.Context) *subsonic.Router {
 	modelScanner := scanner.New(ctx, dataStore, cacheWarmer, broker, playlistsPlaylists, metricsMetrics)
 	playTracker := scrobbler.GetPlayTracker(dataStore, broker, manager)
 	playbackServer := playback.GetInstance(dataStore)
-	router := subsonic.New(dataStore, artworkArtwork, mediaStreamer, archiver, players, provider, modelScanner, broker, playlistsPlaylists, playTracker, share, playbackServer, metricsMetrics)
+	lyricsLyrics := lyrics.NewLyrics(manager)
+	router := subsonic.New(dataStore, artworkArtwork, mediaStreamer, archiver, players, provider, modelScanner, broker, playlistsPlaylists, playTracker, share, playbackServer, metricsMetrics, lyricsLyrics)
 	return router
 }
 
@@ -207,7 +209,7 @@ func getPluginManager() *plugins.Manager {
 
 // wire_injectors.go:
 
-var allProviders = wire.NewSet(core.Set, artwork.Set, server.New, subsonic.New, nativeapi.New, public.New, persistence.New, lastfm.NewRouter, listenbrainz.NewRouter, events.GetBroker, scanner.New, scanner.GetWatcher, metrics.GetPrometheusInstance, db.Db, plugins.GetManager, wire.Bind(new(agents.PluginLoader), new(*plugins.Manager)), wire.Bind(new(scrobbler.PluginLoader), new(*plugins.Manager)), wire.Bind(new(nativeapi.PluginManager), new(*plugins.Manager)), wire.Bind(new(core.PluginUnloader), new(*plugins.Manager)), wire.Bind(new(plugins.PluginMetricsRecorder), new(metrics.Metrics)), wire.Bind(new(core.Watcher), new(scanner.Watcher)))
+var allProviders = wire.NewSet(core.Set, artwork.Set, server.New, subsonic.New, nativeapi.New, public.New, persistence.New, lastfm.NewRouter, listenbrainz.NewRouter, events.GetBroker, scanner.New, scanner.GetWatcher, metrics.GetPrometheusInstance, db.Db, plugins.GetManager, wire.Bind(new(agents.PluginLoader), new(*plugins.Manager)), wire.Bind(new(scrobbler.PluginLoader), new(*plugins.Manager)), wire.Bind(new(lyrics.PluginLoader), new(*plugins.Manager)), wire.Bind(new(nativeapi.PluginManager), new(*plugins.Manager)), wire.Bind(new(core.PluginUnloader), new(*plugins.Manager)), wire.Bind(new(plugins.PluginMetricsRecorder), new(metrics.Metrics)), wire.Bind(new(core.Watcher), new(scanner.Watcher)))
 
 func GetPluginManager(ctx context.Context) *plugins.Manager {
 	manager := getPluginManager()

cmd/wire_injectors.go

@@ -11,6 +11,7 @@ import (
 	"github.com/navidrome/navidrome/core"
 	"github.com/navidrome/navidrome/core/agents"
 	"github.com/navidrome/navidrome/core/artwork"
+	"github.com/navidrome/navidrome/core/lyrics"
 	"github.com/navidrome/navidrome/core/metrics"
 	"github.com/navidrome/navidrome/core/playback"
 	"github.com/navidrome/navidrome/core/scrobbler"
@@ -44,6 +45,7 @@ var allProviders = wire.NewSet(
 	plugins.GetManager,
 	wire.Bind(new(agents.PluginLoader), new(*plugins.Manager)),
 	wire.Bind(new(scrobbler.PluginLoader), new(*plugins.Manager)),
+	wire.Bind(new(lyrics.PluginLoader), new(*plugins.Manager)),
 	wire.Bind(new(nativeapi.PluginManager), new(*plugins.Manager)),
 	wire.Bind(new(core.PluginUnloader), new(*plugins.Manager)),
 	wire.Bind(new(plugins.PluginMetricsRecorder), new(metrics.Metrics)),

core/lyrics/lyrics.go

@@ -9,7 +9,29 @@ import (
 	"github.com/navidrome/navidrome/model"
 )
 
-func GetLyrics(ctx context.Context, mf *model.MediaFile) (model.LyricList, error) {
+// Lyrics can fetch lyrics for a media file.
+type Lyrics interface {
+	GetLyrics(ctx context.Context, mf *model.MediaFile) (model.LyricList, error)
+}
+
+// PluginLoader discovers and loads lyrics provider plugins.
+type PluginLoader interface {
+	LoadLyricsProvider(name string) (Lyrics, bool)
+}
+
+type lyricsService struct {
+	pluginLoader PluginLoader
+}
+
+// NewLyrics creates a new lyrics service. pluginLoader may be nil if no plugin
+// system is available.
+func NewLyrics(pluginLoader PluginLoader) Lyrics {
+	return &lyricsService{pluginLoader: pluginLoader}
+}
+
+// GetLyrics returns lyrics for the given media file, trying sources in the
+// order specified by conf.Server.LyricsPriority.
+func (l *lyricsService) GetLyrics(ctx context.Context, mf *model.MediaFile) (model.LyricList, error) {
 	var lyricsList model.LyricList
 	var err error
 
@@ -21,11 +43,11 @@ func GetLyrics(ctx context.Context, mf *model.MediaFile) (model.LyricList, error
 		case strings.HasPrefix(pattern, "."):
 			lyricsList, err = fromExternalFile(ctx, mf, pattern)
 		default:
-			log.Error(ctx, "Invalid lyric pattern", "pattern", pattern)
+			lyricsList, err = l.fromPlugin(ctx, mf, pattern)
 		}
 
 		if err != nil {
-			log.Error(ctx, "error parsing lyrics", "source", pattern, err)
+			log.Error(ctx, "error getting lyrics", "source", pattern, err)
 		}
 
 		if len(lyricsList) > 0 {

core/lyrics/lyrics_test.go

@@ -3,6 +3,7 @@ package lyrics_test
 import (
 	"context"
 	"encoding/json"
+	"fmt"
 	"os"
 
 	"github.com/navidrome/navidrome/conf"
@@ -72,7 +73,8 @@ var _ = Describe("sources", func() {
 
 	DescribeTable("Lyrics Priority", func(priority string, expected model.LyricList) {
 		conf.Server.LyricsPriority = priority
-		list, err := lyrics.GetLyrics(ctx, &mf)
+		svc := lyrics.NewLyrics(nil)
+		list, err := svc.GetLyrics(ctx, &mf)
 		Expect(err).To(BeNil())
 		Expect(list).To(Equal(expected))
 	},
@@ -107,7 +109,8 @@ var _ = Describe("sources", func() {
 			It("should fallback to embedded if an error happens when parsing file", func() {
 				conf.Server.LyricsPriority = ".mp3,embedded"
 
-				list, err := lyrics.GetLyrics(ctx, &mf)
+				svc := lyrics.NewLyrics(nil)
+				list, err := svc.GetLyrics(ctx, &mf)
 				Expect(err).To(BeNil())
 				Expect(list).To(Equal(embeddedLyrics))
 			})
@@ -115,10 +118,94 @@ var _ = Describe("sources", func() {
 			It("should return nothing if error happens when trying to parse file", func() {
 				conf.Server.LyricsPriority = ".mp3"
 
-				list, err := lyrics.GetLyrics(ctx, &mf)
+				svc := lyrics.NewLyrics(nil)
+				list, err := svc.GetLyrics(ctx, &mf)
 				Expect(err).To(BeNil())
 				Expect(list).To(BeEmpty())
 			})
 		})
 	})
+
+	Context("plugin sources", func() {
+		var mockLoader *mockPluginLoader
+
+		BeforeEach(func() {
+			mockLoader = &mockPluginLoader{}
+		})
+
+		It("should return lyrics from a plugin", func() {
+			conf.Server.LyricsPriority = "test-lyrics-plugin"
+			mockLoader.lyrics = unsyncedLyrics
+			svc := lyrics.NewLyrics(mockLoader)
+			list, err := svc.GetLyrics(ctx, &mf)
+			Expect(err).To(BeNil())
+			Expect(list).To(Equal(unsyncedLyrics))
+		})
+
+		It("should try plugin after embedded returns nothing", func() {
+			conf.Server.LyricsPriority = "embedded,test-lyrics-plugin"
+			mf.Lyrics = "" // No embedded lyrics
+			mockLoader.lyrics = unsyncedLyrics
+			svc := lyrics.NewLyrics(mockLoader)
+			list, err := svc.GetLyrics(ctx, &mf)
+			Expect(err).To(BeNil())
+			Expect(list).To(Equal(unsyncedLyrics))
+		})
+
+		It("should skip plugin if embedded has lyrics", func() {
+			conf.Server.LyricsPriority = "embedded,test-lyrics-plugin"
+			mockLoader.lyrics = unsyncedLyrics
+			svc := lyrics.NewLyrics(mockLoader)
+			list, err := svc.GetLyrics(ctx, &mf)
+			Expect(err).To(BeNil())
+			Expect(list).To(Equal(embeddedLyrics)) // embedded wins
+		})
+
+		It("should skip unknown plugin names gracefully", func() {
+			conf.Server.LyricsPriority = "nonexistent-plugin,embedded"
+			mockLoader.notFound = true
+			svc := lyrics.NewLyrics(mockLoader)
+			list, err := svc.GetLyrics(ctx, &mf)
+			Expect(err).To(BeNil())
+			Expect(list).To(Equal(embeddedLyrics)) // falls through to embedded
+		})
+
+		It("should handle plugin error gracefully", func() {
+			conf.Server.LyricsPriority = "test-lyrics-plugin,embedded"
+			mockLoader.err = fmt.Errorf("plugin error")
+			svc := lyrics.NewLyrics(mockLoader)
+			list, err := svc.GetLyrics(ctx, &mf)
+			Expect(err).To(BeNil())
+			Expect(list).To(Equal(embeddedLyrics)) // falls through to embedded
+		})
+	})
 })
+
+type mockPluginLoader struct {
+	lyrics   model.LyricList
+	err      error
+	notFound bool
+}
+
+func (m *mockPluginLoader) PluginNames(_ string) []string {
+	if m.notFound {
+		return nil
+	}
+	return []string{"test-lyrics-plugin"}
+}
+
+func (m *mockPluginLoader) LoadLyricsProvider(_ string) (lyrics.Lyrics, bool) {
+	if m.notFound {
+		return nil, false
+	}
+	return &mockLyricsProvider{lyrics: m.lyrics, err: m.err}, true
+}
+
+type mockLyricsProvider struct {
+	lyrics model.LyricList
+	err    error
+}
+
+func (m *mockLyricsProvider) GetLyrics(_ context.Context, _ *model.MediaFile) (model.LyricList, error) {
+	return m.lyrics, m.err
+}

core/lyrics/sources.go

@@ -49,3 +49,27 @@ func fromExternalFile(ctx context.Context, mf *model.MediaFile, suffix string) (
 
 	return model.LyricList{*lyrics}, nil
 }
+
+// fromPlugin attempts to load lyrics from a plugin with the given name.
+func (l *lyricsService) fromPlugin(ctx context.Context, mf *model.MediaFile, pluginName string) (model.LyricList, error) {
+	if l.pluginLoader == nil {
+		log.Debug(ctx, "Invalid lyric source", "source", pluginName)
+		return nil, nil
+	}
+
+	provider, ok := l.pluginLoader.LoadLyricsProvider(pluginName)
+	if !ok {
+		log.Warn(ctx, "Lyrics plugin not found", "plugin", pluginName)
+		return nil, nil
+	}
+
+	lyricsList, err := provider.GetLyrics(ctx, mf)
+	if err != nil {
+		return nil, err
+	}
+
+	if len(lyricsList) > 0 {
+		log.Trace(ctx, "Retrieved lyrics from plugin", "plugin", pluginName, "count", len(lyricsList))
+	}
+	return lyricsList, nil
+}

core/wire_providers.go

@@ -5,6 +5,7 @@ import (
 	"github.com/navidrome/navidrome/core/agents"
 	"github.com/navidrome/navidrome/core/external"
 	"github.com/navidrome/navidrome/core/ffmpeg"
+	"github.com/navidrome/navidrome/core/lyrics"
 	"github.com/navidrome/navidrome/core/metrics"
 	"github.com/navidrome/navidrome/core/playback"
 	"github.com/navidrome/navidrome/core/playlists"
@@ -28,4 +29,5 @@ var Set = wire.NewSet(
 	scrobbler.GetPlayTracker,
 	playback.GetInstance,
 	metrics.GetInstance,
+	lyrics.NewLyrics,
 )

plugins/capabilities/lyrics.go

@@ -0,0 +1,26 @@
+package capabilities
+
+// Lyrics provides lyrics for a given track from external sources.
+//
+//nd:capability name=lyrics required=true
+type Lyrics interface {
+	//nd:export name=nd_lyrics_get_lyrics
+	GetLyrics(GetLyricsRequest) (GetLyricsResponse, error)
+}
+
+// GetLyricsRequest contains the track information for lyrics lookup.
+type GetLyricsRequest struct {
+	Track TrackInfo `json:"track"`
+}
+
+// GetLyricsResponse contains the lyrics returned by the plugin.
+type GetLyricsResponse struct {
+	Lyrics []LyricsText `json:"lyrics"`
+}
+
+// LyricsText represents a single set of lyrics in raw text format.
+// Text can be plain text or LRC format — Navidrome will parse it.
+type LyricsText struct {
+	Lang string `json:"lang,omitempty"`
+	Text string `json:"text"`
+}

plugins/capabilities/lyrics.yaml

@@ -0,0 +1,115 @@
+version: v1-draft
+exports:
+    nd_lyrics_get_lyrics:
+        input:
+            $ref: '#/components/schemas/GetLyricsRequest'
+            contentType: application/json
+        output:
+            $ref: '#/components/schemas/GetLyricsResponse'
+            contentType: application/json
+components:
+    schemas:
+        ArtistRef:
+            description: ArtistRef is a reference to an artist with name and optional MBID.
+            properties:
+                id:
+                    type: string
+                    description: ID is the internal Navidrome artist ID (if known).
+                name:
+                    type: string
+                    description: Name is the artist name.
+                mbid:
+                    type: string
+                    description: MBID is the MusicBrainz ID for the artist.
+            required:
+                - name
+        GetLyricsRequest:
+            description: GetLyricsRequest contains the track information for lyrics lookup.
+            properties:
+                track:
+                    $ref: '#/components/schemas/TrackInfo'
+            required:
+                - track
+        GetLyricsResponse:
+            description: GetLyricsResponse contains the lyrics returned by the plugin.
+            properties:
+                lyrics:
+                    type: array
+                    items:
+                        $ref: '#/components/schemas/LyricsText'
+            required:
+                - lyrics
+        LyricsText:
+            description: |-
+                LyricsText represents a single set of lyrics in raw text format.
+                Text can be plain text or LRC format — Navidrome will parse it.
+            properties:
+                lang:
+                    type: string
+                text:
+                    type: string
+            required:
+                - text
+        TrackInfo:
+            description: TrackInfo contains track metadata for scrobbling.
+            properties:
+                id:
+                    type: string
+                    description: ID is the internal Navidrome track ID.
+                title:
+                    type: string
+                    description: Title is the track title.
+                album:
+                    type: string
+                    description: Album is the album name.
+                artist:
+                    type: string
+                    description: Artist is the formatted artist name for display (e.g., "Artist1 • Artist2").
+                albumArtist:
+                    type: string
+                    description: AlbumArtist is the formatted album artist name for display.
+                artists:
+                    type: array
+                    description: Artists is the list of track artists.
+                    items:
+                        $ref: '#/components/schemas/ArtistRef'
+                albumArtists:
+                    type: array
+                    description: AlbumArtists is the list of album artists.
+                    items:
+                        $ref: '#/components/schemas/ArtistRef'
+                duration:
+                    type: number
+                    format: float
+                    description: Duration is the track duration in seconds.
+                trackNumber:
+                    type: integer
+                    format: int32
+                    description: TrackNumber is the track number on the album.
+                discNumber:
+                    type: integer
+                    format: int32
+                    description: DiscNumber is the disc number.
+                mbzRecordingId:
+                    type: string
+                    description: MBZRecordingID is the MusicBrainz recording ID.
+                mbzAlbumId:
+                    type: string
+                    description: MBZAlbumID is the MusicBrainz album/release ID.
+                mbzReleaseGroupId:
+                    type: string
+                    description: MBZReleaseGroupID is the MusicBrainz release group ID.
+                mbzReleaseTrackId:
+                    type: string
+                    description: MBZReleaseTrackID is the MusicBrainz release track ID.
+            required:
+                - id
+                - title
+                - album
+                - artist
+                - albumArtist
+                - artists
+                - albumArtists
+                - duration
+                - trackNumber
+                - discNumber

plugins/host/kvstore.go

@@ -23,20 +23,6 @@ type KVStoreService interface {
 	//nd:hostfunc
 	Set(ctx context.Context, key string, value []byte) error
 
-	// SetWithTTL stores a byte value with the given key and a time-to-live.
-	//
-	// After ttlSeconds, the key is treated as non-existent and will be
-	// cleaned up lazily. ttlSeconds must be greater than 0.
-	//
-	// Parameters:
-	//   - key: The storage key (max 256 bytes, UTF-8)
-	//   - value: The byte slice to store
-	//   - ttlSeconds: Time-to-live in seconds (must be > 0)
-	//
-	// Returns an error if the storage limit would be exceeded or the operation fails.
-	//nd:hostfunc
-	SetWithTTL(ctx context.Context, key string, value []byte, ttlSeconds int64) error
-
 	// Get retrieves a byte value from storage.
 	//
 	// Parameters:
@@ -46,15 +32,14 @@ type KVStoreService interface {
 	//nd:hostfunc
 	Get(ctx context.Context, key string) (value []byte, exists bool, err error)
 
-	// GetMany retrieves multiple values in a single call.
+	// Delete removes a value from storage.
 	//
 	// Parameters:
-	//   - keys: The storage keys to retrieve
+	//   - key: The storage key
 	//
-	// Returns a map of key to value for keys that exist and have not expired.
-	// Missing or expired keys are omitted from the result.
+	// Returns an error if the operation fails. Does not return an error if the key doesn't exist.
 	//nd:hostfunc
-	GetMany(ctx context.Context, keys []string) (values map[string][]byte, err error)
+	Delete(ctx context.Context, key string) error
 
 	// Has checks if a key exists in storage.
 	//
@@ -74,24 +59,6 @@ type KVStoreService interface {
 	//nd:hostfunc
 	List(ctx context.Context, prefix string) (keys []string, err error)
 
-	// Delete removes a value from storage.
-	//
-	// Parameters:
-	//   - key: The storage key
-	//
-	// Returns an error if the operation fails. Does not return an error if the key doesn't exist.
-	//nd:hostfunc
-	Delete(ctx context.Context, key string) error
-
-	// DeleteByPrefix removes all keys matching the given prefix.
-	//
-	// Parameters:
-	//   - prefix: Key prefix to match (must not be empty)
-	//
-	// Returns the number of keys deleted. Includes expired keys.
-	//nd:hostfunc
-	DeleteByPrefix(ctx context.Context, prefix string) (deletedCount int64, err error)
-
 	// GetStorageUsed returns the total storage used by this plugin in bytes.
 	//nd:hostfunc
 	GetStorageUsed(ctx context.Context) (bytes int64, err error)

plugins/host/kvstore_gen.go

@@ -20,18 +20,6 @@ type KVStoreSetResponse struct {
 	Error string `json:"error,omitempty"`
 }
 
-// KVStoreSetWithTTLRequest is the request type for KVStore.SetWithTTL.
-type KVStoreSetWithTTLRequest struct {
-	Key        string `json:"key"`
-	Value      []byte `json:"value"`
-	TtlSeconds int64  `json:"ttlSeconds"`
-}
-
-// KVStoreSetWithTTLResponse is the response type for KVStore.SetWithTTL.
-type KVStoreSetWithTTLResponse struct {
-	Error string `json:"error,omitempty"`
-}
-
 // KVStoreGetRequest is the request type for KVStore.Get.
 type KVStoreGetRequest struct {
 	Key string `json:"key"`
@@ -44,15 +32,14 @@ type KVStoreGetResponse struct {
 	Error  string `json:"error,omitempty"`
 }
 
-// KVStoreGetManyRequest is the request type for KVStore.GetMany.
-type KVStoreGetManyRequest struct {
-	Keys []string `json:"keys"`
+// KVStoreDeleteRequest is the request type for KVStore.Delete.
+type KVStoreDeleteRequest struct {
+	Key string `json:"key"`
 }
 
-// KVStoreGetManyResponse is the response type for KVStore.GetMany.
-type KVStoreGetManyResponse struct {
-	Values map[string][]byte `json:"values,omitempty"`
-	Error  string            `json:"error,omitempty"`
+// KVStoreDeleteResponse is the response type for KVStore.Delete.
+type KVStoreDeleteResponse struct {
+	Error string `json:"error,omitempty"`
 }
 
 // KVStoreHasRequest is the request type for KVStore.Has.
@@ -77,27 +64,6 @@ type KVStoreListResponse struct {
 	Error string   `json:"error,omitempty"`
 }
 
-// KVStoreDeleteRequest is the request type for KVStore.Delete.
-type KVStoreDeleteRequest struct {
-	Key string `json:"key"`
-}
-
-// KVStoreDeleteResponse is the response type for KVStore.Delete.
-type KVStoreDeleteResponse struct {
-	Error string `json:"error,omitempty"`
-}
-
-// KVStoreDeleteByPrefixRequest is the request type for KVStore.DeleteByPrefix.
-type KVStoreDeleteByPrefixRequest struct {
-	Prefix string `json:"prefix"`
-}
-
-// KVStoreDeleteByPrefixResponse is the response type for KVStore.DeleteByPrefix.
-type KVStoreDeleteByPrefixResponse struct {
-	DeletedCount int64  `json:"deletedCount,omitempty"`
-	Error        string `json:"error,omitempty"`
-}
-
 // KVStoreGetStorageUsedResponse is the response type for KVStore.GetStorageUsed.
 type KVStoreGetStorageUsedResponse struct {
 	Bytes int64  `json:"bytes,omitempty"`
@@ -109,13 +75,10 @@ type KVStoreGetStorageUsedResponse struct {
 func RegisterKVStoreHostFunctions(service KVStoreService) []extism.HostFunction {
 	return []extism.HostFunction{
 		newKVStoreSetHostFunction(service),
-		newKVStoreSetWithTTLHostFunction(service),
 		newKVStoreGetHostFunction(service),
-		newKVStoreGetManyHostFunction(service),
+		newKVStoreDeleteHostFunction(service),
 		newKVStoreHasHostFunction(service),
 		newKVStoreListHostFunction(service),
-		newKVStoreDeleteHostFunction(service),
-		newKVStoreDeleteByPrefixHostFunction(service),
 		newKVStoreGetStorageUsedHostFunction(service),
 	}
 }
@@ -151,37 +114,6 @@ func newKVStoreSetHostFunction(service KVStoreService) extism.HostFunction {
 	)
 }
 
-func newKVStoreSetWithTTLHostFunction(service KVStoreService) extism.HostFunction {
-	return extism.NewHostFunctionWithStack(
-		"kvstore_setwithttl",
-		func(ctx context.Context, p *extism.CurrentPlugin, stack []uint64) {
-			// Read JSON request from plugin memory
-			reqBytes, err := p.ReadBytes(stack[0])
-			if err != nil {
-				kvstoreWriteError(p, stack, err)
-				return
-			}
-			var req KVStoreSetWithTTLRequest
-			if err := json.Unmarshal(reqBytes, &req); err != nil {
-				kvstoreWriteError(p, stack, err)
-				return
-			}
-
-			// Call the service method
-			if svcErr := service.SetWithTTL(ctx, req.Key, req.Value, req.TtlSeconds); svcErr != nil {
-				kvstoreWriteError(p, stack, svcErr)
-				return
-			}
-
-			// Write JSON response to plugin memory
-			resp := KVStoreSetWithTTLResponse{}
-			kvstoreWriteResponse(p, stack, resp)
-		},
-		[]extism.ValueType{extism.ValueTypePTR},
-		[]extism.ValueType{extism.ValueTypePTR},
-	)
-}
-
 func newKVStoreGetHostFunction(service KVStoreService) extism.HostFunction {
 	return extism.NewHostFunctionWithStack(
 		"kvstore_get",
@@ -217,9 +149,9 @@ func newKVStoreGetHostFunction(service KVStoreService) extism.HostFunction {
 	)
 }
 
-func newKVStoreGetManyHostFunction(service KVStoreService) extism.HostFunction {
+func newKVStoreDeleteHostFunction(service KVStoreService) extism.HostFunction {
 	return extism.NewHostFunctionWithStack(
-		"kvstore_getmany",
+		"kvstore_delete",
 		func(ctx context.Context, p *extism.CurrentPlugin, stack []uint64) {
 			// Read JSON request from plugin memory
 			reqBytes, err := p.ReadBytes(stack[0])
@@ -227,23 +159,20 @@ func newKVStoreGetManyHostFunction(service KVStoreService) extism.HostFunction {
 				kvstoreWriteError(p, stack, err)
 				return
 			}
-			var req KVStoreGetManyRequest
+			var req KVStoreDeleteRequest
 			if err := json.Unmarshal(reqBytes, &req); err != nil {
 				kvstoreWriteError(p, stack, err)
 				return
 			}
 
 			// Call the service method
-			values, svcErr := service.GetMany(ctx, req.Keys)
-			if svcErr != nil {
+			if svcErr := service.Delete(ctx, req.Key); svcErr != nil {
 				kvstoreWriteError(p, stack, svcErr)
 				return
 			}
 
 			// Write JSON response to plugin memory
-			resp := KVStoreGetManyResponse{
-				Values: values,
-			}
+			resp := KVStoreDeleteResponse{}
 			kvstoreWriteResponse(p, stack, resp)
 		},
 		[]extism.ValueType{extism.ValueTypePTR},
@@ -319,71 +248,6 @@ func newKVStoreListHostFunction(service KVStoreService) extism.HostFunction {
 	)
 }
 
-func newKVStoreDeleteHostFunction(service KVStoreService) extism.HostFunction {
-	return extism.NewHostFunctionWithStack(
-		"kvstore_delete",
-		func(ctx context.Context, p *extism.CurrentPlugin, stack []uint64) {
-			// Read JSON request from plugin memory
-			reqBytes, err := p.ReadBytes(stack[0])
-			if err != nil {
-				kvstoreWriteError(p, stack, err)
-				return
-			}
-			var req KVStoreDeleteRequest
-			if err := json.Unmarshal(reqBytes, &req); err != nil {
-				kvstoreWriteError(p, stack, err)
-				return
-			}
-
-			// Call the service method
-			if svcErr := service.Delete(ctx, req.Key); svcErr != nil {
-				kvstoreWriteError(p, stack, svcErr)
-				return
-			}
-
-			// Write JSON response to plugin memory
-			resp := KVStoreDeleteResponse{}
-			kvstoreWriteResponse(p, stack, resp)
-		},
-		[]extism.ValueType{extism.ValueTypePTR},
-		[]extism.ValueType{extism.ValueTypePTR},
-	)
-}
-
-func newKVStoreDeleteByPrefixHostFunction(service KVStoreService) extism.HostFunction {
-	return extism.NewHostFunctionWithStack(
-		"kvstore_deletebyprefix",
-		func(ctx context.Context, p *extism.CurrentPlugin, stack []uint64) {
-			// Read JSON request from plugin memory
-			reqBytes, err := p.ReadBytes(stack[0])
-			if err != nil {
-				kvstoreWriteError(p, stack, err)
-				return
-			}
-			var req KVStoreDeleteByPrefixRequest
-			if err := json.Unmarshal(reqBytes, &req); err != nil {
-				kvstoreWriteError(p, stack, err)
-				return
-			}
-
-			// Call the service method
-			deletedcount, svcErr := service.DeleteByPrefix(ctx, req.Prefix)
-			if svcErr != nil {
-				kvstoreWriteError(p, stack, svcErr)
-				return
-			}
-
-			// Write JSON response to plugin memory
-			resp := KVStoreDeleteByPrefixResponse{
-				DeletedCount: deletedcount,
-			}
-			kvstoreWriteResponse(p, stack, resp)
-		},
-		[]extism.ValueType{extism.ValueTypePTR},
-		[]extism.ValueType{extism.ValueTypePTR},
-	)
-}
-
 func newKVStoreGetStorageUsedHostFunction(service KVStoreService) extism.HostFunction {
 	return extism.NewHostFunctionWithStack(
 		"kvstore_getstorageused",

plugins/host_kvstore.go

@@ -7,16 +7,14 @@ import (
 	"fmt"
 	"os"
 	"path/filepath"
-	"slices"
 	"strings"
-	"time"
+	"sync/atomic"
 
 	"github.com/dustin/go-humanize"
 	_ "github.com/mattn/go-sqlite3"
 	"github.com/navidrome/navidrome/conf"
 	"github.com/navidrome/navidrome/log"
 	"github.com/navidrome/navidrome/plugins/host"
-	"github.com/navidrome/navidrome/utils/slice"
 )
 
 const (
@@ -24,22 +22,17 @@ const (
 	maxKeyLength          = 256             // Max key length in bytes
 )
 
-// notExpiredFilter is the SQL condition to exclude expired keys.
-const notExpiredFilter = "(expires_at IS NULL OR expires_at > datetime('now'))"
-
-const cleanupInterval = 1 * time.Hour
-
 // kvstoreServiceImpl implements the host.KVStoreService interface.
 // Each plugin gets its own SQLite database for isolation.
 type kvstoreServiceImpl struct {
-	pluginName string
-	db         *sql.DB
-	maxSize    int64
+	pluginName  string
+	db          *sql.DB
+	maxSize     int64
+	currentSize atomic.Int64 // cached total size, updated on Set/Delete
 }
 
 // newKVStoreService creates a new kvstoreServiceImpl instance with its own SQLite database.
-// The provided context controls the lifetime of the background cleanup goroutine.
-func newKVStoreService(ctx context.Context, pluginName string, perm *KVStorePermission) (*kvstoreServiceImpl, error) {
+func newKVStoreService(pluginName string, perm *KVStorePermission) (*kvstoreServiceImpl, error) {
 	// Parse max size from permission, default to 1MB
 	maxSize := int64(defaultMaxKVStoreSize)
 	if perm != nil && perm.MaxSize != nil && *perm.MaxSize != "" {
@@ -66,69 +59,46 @@ func newKVStoreService(ctx context.Context, pluginName string, perm *KVStorePerm
 	db.SetMaxOpenConns(3)
 	db.SetMaxIdleConns(1)
 
-	// Apply schema migrations
+	// Create schema
 	if err := createKVStoreSchema(db); err != nil {
 		db.Close()
-		return nil, fmt.Errorf("migrating kvstore schema: %w", err)
+		return nil, fmt.Errorf("creating kvstore schema: %w", err)
 	}
 
-	log.Debug("Initialized plugin kvstore", "plugin", pluginName, "path", dbPath, "maxSize", humanize.Bytes(uint64(maxSize)))
+	// Load current storage size from database
+	var currentSize int64
+	if err := db.QueryRow(`SELECT COALESCE(SUM(size), 0) FROM kvstore`).Scan(&currentSize); err != nil {
+		db.Close()
+		return nil, fmt.Errorf("loading storage size: %w", err)
+	}
+
+	log.Debug("Initialized plugin kvstore", "plugin", pluginName, "path", dbPath, "maxSize", humanize.Bytes(uint64(maxSize)), "currentSize", humanize.Bytes(uint64(currentSize)))
 
 	svc := &kvstoreServiceImpl{
 		pluginName: pluginName,
 		db:         db,
 		maxSize:    maxSize,
 	}
-	go svc.cleanupLoop(ctx)
+	svc.currentSize.Store(currentSize)
 	return svc, nil
 }
 
-// createKVStoreSchema applies schema migrations to the kvstore database.
-// New migrations must be appended at the end of the slice.
 func createKVStoreSchema(db *sql.DB) error {
-	return migrateDB(db, []string{
-		`CREATE TABLE IF NOT EXISTS kvstore (
+	_, err := db.Exec(`
+		CREATE TABLE IF NOT EXISTS kvstore (
 			key TEXT PRIMARY KEY NOT NULL,
 			value BLOB NOT NULL,
 			size INTEGER NOT NULL,
 			created_at DATETIME NOT NULL DEFAULT CURRENT_TIMESTAMP,
 			updated_at DATETIME NOT NULL DEFAULT CURRENT_TIMESTAMP
-		)`,
-		`ALTER TABLE kvstore ADD COLUMN expires_at DATETIME DEFAULT NULL`,
-		`CREATE INDEX idx_kvstore_expires_at ON kvstore(expires_at)`,
-	})
+		)
+	`)
+	return err
 }
 
-// storageUsed returns the current total storage used by non-expired keys.
-func (s *kvstoreServiceImpl) storageUsed(ctx context.Context) (int64, error) {
-	var used int64
-	err := s.db.QueryRowContext(ctx, `SELECT COALESCE(SUM(size), 0) FROM kvstore WHERE `+notExpiredFilter).Scan(&used)
-	if err != nil {
-		return 0, fmt.Errorf("calculating storage used: %w", err)
-	}
-	return used, nil
-}
-
-// checkStorageLimit verifies that adding delta bytes would not exceed the storage limit.
-func (s *kvstoreServiceImpl) checkStorageLimit(ctx context.Context, delta int64) error {
-	if delta <= 0 {
-		return nil
-	}
-	used, err := s.storageUsed(ctx)
-	if err != nil {
-		return err
-	}
-	newTotal := used + delta
-	if newTotal > s.maxSize {
-		return fmt.Errorf("storage limit exceeded: would use %s of %s allowed",
-			humanize.Bytes(uint64(newTotal)), humanize.Bytes(uint64(s.maxSize)))
-	}
-	return nil
-}
-
-// setValue is the shared implementation for Set and SetWithTTL.
-// A ttlSeconds of 0 means no expiration.
-func (s *kvstoreServiceImpl) setValue(ctx context.Context, key string, value []byte, ttlSeconds int64) error {
+// Set stores a byte value with the given key.
+func (s *kvstoreServiceImpl) Set(ctx context.Context, key string, value []byte) error {
+	// Validate key
 	if len(key) == 0 {
 		return fmt.Errorf("key cannot be empty")
 	}
@@ -138,59 +108,46 @@ func (s *kvstoreServiceImpl) setValue(ctx context.Context, key string, value []b
 
 	newValueSize := int64(len(value))
 
-	// Get current size of this key (if it exists and not expired) to calculate delta
+	// Get current size of this key (if it exists) to calculate delta
 	var oldSize int64
-	err := s.db.QueryRowContext(ctx, `SELECT COALESCE(size, 0) FROM kvstore WHERE key = ? AND `+notExpiredFilter, key).Scan(&oldSize)
+	err := s.db.QueryRowContext(ctx, `SELECT COALESCE(size, 0) FROM kvstore WHERE key = ?`, key).Scan(&oldSize)
 	if err != nil && !errors.Is(err, sql.ErrNoRows) {
 		return fmt.Errorf("checking existing key: %w", err)
 	}
 
-	if err := s.checkStorageLimit(ctx, newValueSize-oldSize); err != nil {
-		return err
-	}
-
-	// Compute expires_at: sql.NullString{Valid:false} sends NULL (no expiration),
-	// otherwise we send a concrete timestamp.
-	var expiresAt sql.NullString
-	if ttlSeconds > 0 {
-		expiresAt = sql.NullString{String: fmt.Sprintf("+%d seconds", ttlSeconds), Valid: true}
+	// Check size limits using cached total
+	delta := newValueSize - oldSize
+	newTotal := s.currentSize.Load() + delta
+	if newTotal > s.maxSize {
+		return fmt.Errorf("storage limit exceeded: would use %s of %s allowed",
+			humanize.Bytes(uint64(newTotal)), humanize.Bytes(uint64(s.maxSize)))
 	}
 
+	// Upsert the value
 	_, err = s.db.ExecContext(ctx, `
-		INSERT INTO kvstore (key, value, size, created_at, updated_at, expires_at)
-		VALUES (?, ?, ?, CURRENT_TIMESTAMP, CURRENT_TIMESTAMP, datetime('now', ?))
-		ON CONFLICT(key) DO UPDATE SET
-			value = excluded.value,
+		INSERT INTO kvstore (key, value, size, created_at, updated_at) 
+		VALUES (?, ?, ?, CURRENT_TIMESTAMP, CURRENT_TIMESTAMP)
+		ON CONFLICT(key) DO UPDATE SET 
+			value = excluded.value, 
 			size = excluded.size,
-			updated_at = CURRENT_TIMESTAMP,
-			expires_at = excluded.expires_at
-	`, key, value, newValueSize, expiresAt)
+			updated_at = CURRENT_TIMESTAMP
+	`, key, value, newValueSize)
 	if err != nil {
 		return fmt.Errorf("storing value: %w", err)
 	}
 
-	log.Trace(ctx, "KVStore.Set", "plugin", s.pluginName, "key", key, "size", newValueSize, "ttlSeconds", ttlSeconds)
+	// Update cached size
+	s.currentSize.Add(delta)
+
+	log.Trace(ctx, "KVStore.Set", "plugin", s.pluginName, "key", key, "size", newValueSize)
 	return nil
 }
 
-// Set stores a byte value with the given key.
-func (s *kvstoreServiceImpl) Set(ctx context.Context, key string, value []byte) error {
-	return s.setValue(ctx, key, value, 0)
-}
-
-// SetWithTTL stores a byte value with the given key and a time-to-live.
-func (s *kvstoreServiceImpl) SetWithTTL(ctx context.Context, key string, value []byte, ttlSeconds int64) error {
-	if ttlSeconds <= 0 {
-		return fmt.Errorf("ttlSeconds must be greater than 0")
-	}
-	return s.setValue(ctx, key, value, ttlSeconds)
-}
-
 // Get retrieves a byte value from storage.
 func (s *kvstoreServiceImpl) Get(ctx context.Context, key string) ([]byte, bool, error) {
 	var value []byte
-	err := s.db.QueryRowContext(ctx, `SELECT value FROM kvstore WHERE key = ? AND `+notExpiredFilter, key).Scan(&value)
-	if errors.Is(err, sql.ErrNoRows) {
+	err := s.db.QueryRowContext(ctx, `SELECT value FROM kvstore WHERE key = ?`, key).Scan(&value)
+	if err == sql.ErrNoRows {
 		return nil, false, nil
 	}
 	if err != nil {
@@ -203,11 +160,25 @@ func (s *kvstoreServiceImpl) Get(ctx context.Context, key string) ([]byte, bool,
 
 // Delete removes a value from storage.
 func (s *kvstoreServiceImpl) Delete(ctx context.Context, key string) error {
-	_, err := s.db.ExecContext(ctx, `DELETE FROM kvstore WHERE key = ?`, key)
+	// Get size of the key being deleted to update cache
+	var oldSize int64
+	err := s.db.QueryRowContext(ctx, `SELECT size FROM kvstore WHERE key = ?`, key).Scan(&oldSize)
+	if errors.Is(err, sql.ErrNoRows) {
+		// Key doesn't exist, nothing to delete
+		return nil
+	}
+	if err != nil {
+		return fmt.Errorf("checking key size: %w", err)
+	}
+
+	_, err = s.db.ExecContext(ctx, `DELETE FROM kvstore WHERE key = ?`, key)
 	if err != nil {
 		return fmt.Errorf("deleting value: %w", err)
 	}
 
+	// Update cached size
+	s.currentSize.Add(-oldSize)
+
 	log.Trace(ctx, "KVStore.Delete", "plugin", s.pluginName, "key", key)
 	return nil
 }
@@ -215,7 +186,7 @@ func (s *kvstoreServiceImpl) Delete(ctx context.Context, key string) error {
 // Has checks if a key exists in storage.
 func (s *kvstoreServiceImpl) Has(ctx context.Context, key string) (bool, error) {
 	var count int
-	err := s.db.QueryRowContext(ctx, `SELECT COUNT(*) FROM kvstore WHERE key = ? AND `+notExpiredFilter, key).Scan(&count)
+	err := s.db.QueryRowContext(ctx, `SELECT COUNT(*) FROM kvstore WHERE key = ?`, key).Scan(&count)
 	if err != nil {
 		return false, fmt.Errorf("checking key: %w", err)
 	}
@@ -229,12 +200,12 @@ func (s *kvstoreServiceImpl) List(ctx context.Context, prefix string) ([]string,
 	var err error
 
 	if prefix == "" {
-		rows, err = s.db.QueryContext(ctx, `SELECT key FROM kvstore WHERE `+notExpiredFilter+` ORDER BY key`)
+		rows, err = s.db.QueryContext(ctx, `SELECT key FROM kvstore ORDER BY key`)
 	} else {
 		// Escape special LIKE characters in prefix
 		escapedPrefix := strings.ReplaceAll(prefix, "%", "\\%")
 		escapedPrefix = strings.ReplaceAll(escapedPrefix, "_", "\\_")
-		rows, err = s.db.QueryContext(ctx, `SELECT key FROM kvstore WHERE key LIKE ? ESCAPE '\' AND `+notExpiredFilter+` ORDER BY key`, escapedPrefix+"%")
+		rows, err = s.db.QueryContext(ctx, `SELECT key FROM kvstore WHERE key LIKE ? ESCAPE '\' ORDER BY key`, escapedPrefix+"%")
 	}
 	if err != nil {
 		return nil, fmt.Errorf("listing keys: %w", err)
@@ -260,113 +231,16 @@ func (s *kvstoreServiceImpl) List(ctx context.Context, prefix string) ([]string,
 
 // GetStorageUsed returns the total storage used by this plugin in bytes.
 func (s *kvstoreServiceImpl) GetStorageUsed(ctx context.Context) (int64, error) {
-	used, err := s.storageUsed(ctx)
-	if err != nil {
-		return 0, err
-	}
+	used := s.currentSize.Load()
 	log.Trace(ctx, "KVStore.GetStorageUsed", "plugin", s.pluginName, "bytes", used)
 	return used, nil
 }
 
-// DeleteByPrefix removes all keys matching the given prefix.
-func (s *kvstoreServiceImpl) DeleteByPrefix(ctx context.Context, prefix string) (int64, error) {
-	if prefix == "" {
-		return 0, fmt.Errorf("prefix cannot be empty")
-	}
-
-	escapedPrefix := strings.ReplaceAll(prefix, "%", "\\%")
-	escapedPrefix = strings.ReplaceAll(escapedPrefix, "_", "\\_")
-	result, err := s.db.ExecContext(ctx, `DELETE FROM kvstore WHERE key LIKE ? ESCAPE '\'`, escapedPrefix+"%")
-	if err != nil {
-		return 0, fmt.Errorf("deleting keys: %w", err)
-	}
-
-	count, err := result.RowsAffected()
-	if err != nil {
-		return 0, fmt.Errorf("getting deleted count: %w", err)
-	}
-
-	log.Trace(ctx, "KVStore.DeleteByPrefix", "plugin", s.pluginName, "prefix", prefix, "deletedCount", count)
-	return count, nil
-}
-
-// GetMany retrieves multiple values in a single call, processing keys in batches.
-func (s *kvstoreServiceImpl) GetMany(ctx context.Context, keys []string) (map[string][]byte, error) {
-	if len(keys) == 0 {
-		return map[string][]byte{}, nil
-	}
-
-	const batchSize = 200
-	result := make(map[string][]byte)
-	for chunk := range slice.CollectChunks(slices.Values(keys), batchSize) {
-		placeholders := make([]string, len(chunk))
-		args := make([]any, len(chunk))
-		for i, key := range chunk {
-			placeholders[i] = "?"
-			args[i] = key
-		}
-
-		query := `SELECT key, value FROM kvstore WHERE key IN (` + strings.Join(placeholders, ",") + `) AND ` + notExpiredFilter //nolint:gosec // placeholders are always "?"
-		rows, err := s.db.QueryContext(ctx, query, args...)
-		if err != nil {
-			return nil, fmt.Errorf("querying values: %w", err)
-		}
-
-		for rows.Next() {
-			var key string
-			var value []byte
-			if err := rows.Scan(&key, &value); err != nil {
-				rows.Close()
-				return nil, fmt.Errorf("scanning value: %w", err)
-			}
-			result[key] = value
-		}
-		if err := rows.Err(); err != nil {
-			rows.Close()
-			return nil, fmt.Errorf("iterating values: %w", err)
-		}
-		rows.Close()
-	}
-
-	log.Trace(ctx, "KVStore.GetMany", "plugin", s.pluginName, "requested", len(keys), "found", len(result))
-	return result, nil
-}
-
-// cleanupLoop periodically removes expired keys from the database.
-// It stops when the provided context is cancelled.
-func (s *kvstoreServiceImpl) cleanupLoop(ctx context.Context) {
-	ticker := time.NewTicker(cleanupInterval)
-	defer ticker.Stop()
-	for {
-		select {
-		case <-ctx.Done():
-			return
-		case <-ticker.C:
-			s.cleanupExpired(ctx)
-		}
-	}
-}
-
-// cleanupExpired removes all expired keys from the database to reclaim disk space.
-func (s *kvstoreServiceImpl) cleanupExpired(ctx context.Context) {
-	result, err := s.db.ExecContext(ctx, `DELETE FROM kvstore WHERE expires_at IS NOT NULL AND expires_at <= datetime('now')`)
-	if err != nil {
-		log.Error(ctx, "KVStore cleanup: failed to delete expired keys", "plugin", s.pluginName, err)
-		return
-	}
-	if count, err := result.RowsAffected(); err == nil && count > 0 {
-		log.Debug("KVStore cleanup completed", "plugin", s.pluginName, "deletedKeys", count)
-	}
-}
-
-// Close runs a final cleanup and closes the SQLite database connection.
-// The cleanup goroutine is stopped by the context passed to newKVStoreService.
+// Close closes the SQLite database connection.
+// This is called when the plugin is unloaded.
 func (s *kvstoreServiceImpl) Close() error {
 	if s.db != nil {
 		log.Debug("Closing plugin kvstore", "plugin", s.pluginName)
-		ctx, cancel := context.WithTimeout(context.Background(), 5*time.Second)
-		defer cancel()
-		s.cleanupExpired(ctx)
 		return s.db.Close()
 	}
 	return nil

plugins/host_kvstore_test.go

@@ -12,7 +12,6 @@ import (
 	"os"
 	"path/filepath"
 	"strings"
-	"time"
 
 	"github.com/navidrome/navidrome/conf"
 	"github.com/navidrome/navidrome/conf/configtest"
@@ -38,7 +37,7 @@ var _ = Describe("KVStoreService", func() {
 
 		// Create service with 1KB limit for testing
 		maxSize := "1KB"
-		service, err = newKVStoreService(ctx, "test_plugin", &KVStorePermission{MaxSize: &maxSize})
+		service, err = newKVStoreService("test_plugin", &KVStorePermission{MaxSize: &maxSize})
 		Expect(err).ToNot(HaveOccurred())
 	})
 
@@ -254,7 +253,7 @@ var _ = Describe("KVStoreService", func() {
 			Expect(service.Close()).To(Succeed())
 
 			maxSize := "1KB"
-			service2, err := newKVStoreService(ctx, "test_plugin", &KVStorePermission{MaxSize: &maxSize})
+			service2, err := newKVStoreService("test_plugin", &KVStorePermission{MaxSize: &maxSize})
 			Expect(err).ToNot(HaveOccurred())
 			defer service2.Close()
 
@@ -303,7 +302,7 @@ var _ = Describe("KVStoreService", func() {
 
 	Describe("Plugin Isolation", func() {
 		It("isolates data between plugins", func() {
-			service2, err := newKVStoreService(ctx, "other_plugin", &KVStorePermission{})
+			service2, err := newKVStoreService("other_plugin", &KVStorePermission{})
 			Expect(err).ToNot(HaveOccurred())
 			defer service2.Close()
 
@@ -322,7 +321,7 @@ var _ = Describe("KVStoreService", func() {
 		})
 
 		It("creates separate database files per plugin", func() {
-			service2, err := newKVStoreService(ctx, "other_plugin", &KVStorePermission{})
+			service2, err := newKVStoreService("other_plugin", &KVStorePermission{})
 			Expect(err).ToNot(HaveOccurred())
 			defer service2.Close()
 
@@ -344,309 +343,6 @@ var _ = Describe("KVStoreService", func() {
 			Expect(err).To(HaveOccurred())
 		})
 	})
-
-	Describe("TTL Expiration", func() {
-		It("Get returns not-exists for expired keys", func() {
-			_, err := service.db.Exec(`
-				INSERT INTO kvstore (key, value, size, expires_at)
-				VALUES ('expired_key', 'old', 3, datetime('now', '-1 seconds'))
-			`)
-			Expect(err).ToNot(HaveOccurred())
-			value, exists, err := service.Get(ctx, "expired_key")
-			Expect(err).ToNot(HaveOccurred())
-			Expect(exists).To(BeFalse())
-			Expect(value).To(BeNil())
-		})
-		It("Has returns false for expired keys", func() {
-			_, err := service.db.Exec(`
-				INSERT INTO kvstore (key, value, size, expires_at)
-				VALUES ('expired_has', 'old', 3, datetime('now', '-1 seconds'))
-			`)
-			Expect(err).ToNot(HaveOccurred())
-			exists, err := service.Has(ctx, "expired_has")
-			Expect(err).ToNot(HaveOccurred())
-			Expect(exists).To(BeFalse())
-		})
-		It("List excludes expired keys", func() {
-			Expect(service.Set(ctx, "live:1", []byte("alive"))).To(Succeed())
-			_, err := service.db.Exec(`
-				INSERT INTO kvstore (key, value, size, expires_at)
-				VALUES ('live:expired', 'dead', 4, datetime('now', '-1 seconds'))
-			`)
-			Expect(err).ToNot(HaveOccurred())
-			keys, err := service.List(ctx, "live:")
-			Expect(err).ToNot(HaveOccurred())
-			Expect(keys).To(HaveLen(1))
-			Expect(keys).To(ContainElement("live:1"))
-		})
-		It("Get returns value for non-expired keys with TTL", func() {
-			_, err := service.db.Exec(`
-				INSERT INTO kvstore (key, value, size, expires_at)
-				VALUES ('future_key', 'still alive', 11, datetime('now', '+3600 seconds'))
-			`)
-			Expect(err).ToNot(HaveOccurred())
-			value, exists, err := service.Get(ctx, "future_key")
-			Expect(err).ToNot(HaveOccurred())
-			Expect(exists).To(BeTrue())
-			Expect(value).To(Equal([]byte("still alive")))
-		})
-		It("Set clears expires_at from a key previously set with TTL", func() {
-			// Insert a key with a TTL that has already expired
-			_, err := service.db.Exec(`
-				INSERT INTO kvstore (key, value, size, expires_at)
-				VALUES ('ttl_then_set', 'temp', 4, datetime('now', '-1 seconds'))
-			`)
-			Expect(err).ToNot(HaveOccurred())
-
-			// Overwrite with Set (no TTL) — should become permanent
-			err = service.Set(ctx, "ttl_then_set", []byte("permanent"))
-			Expect(err).ToNot(HaveOccurred())
-
-			// Should exist because Set cleared expires_at
-			value, exists, err := service.Get(ctx, "ttl_then_set")
-			Expect(err).ToNot(HaveOccurred())
-			Expect(exists).To(BeTrue())
-			Expect(value).To(Equal([]byte("permanent")))
-
-			// Verify expires_at is actually NULL
-			var expiresAt *string
-			Expect(service.db.QueryRow(`SELECT expires_at FROM kvstore WHERE key = 'ttl_then_set'`).Scan(&expiresAt)).To(Succeed())
-			Expect(expiresAt).To(BeNil())
-		})
-		It("expired keys are not counted in storage used", func() {
-			_, err := service.db.Exec(`
-				INSERT INTO kvstore (key, value, size, expires_at)
-				VALUES ('expired_key', '12345', 5, datetime('now', '-1 seconds'))
-			`)
-			Expect(err).ToNot(HaveOccurred())
-
-			// Expired keys should not be counted
-			used, err := service.GetStorageUsed(ctx)
-			Expect(err).ToNot(HaveOccurred())
-			Expect(used).To(Equal(int64(0)))
-		})
-		It("cleanup removes expired rows from disk", func() {
-			_, err := service.db.Exec(`
-				INSERT INTO kvstore (key, value, size, expires_at)
-				VALUES ('cleanup_me', '12345', 5, datetime('now', '-1 seconds'))
-			`)
-			Expect(err).ToNot(HaveOccurred())
-
-			// Row exists in DB but is logically expired
-			var count int
-			Expect(service.db.QueryRow(`SELECT COUNT(*) FROM kvstore`).Scan(&count)).To(Succeed())
-			Expect(count).To(Equal(1))
-
-			service.cleanupExpired(ctx)
-
-			// Row should be physically deleted
-			Expect(service.db.QueryRow(`SELECT COUNT(*) FROM kvstore`).Scan(&count)).To(Succeed())
-			Expect(count).To(Equal(0))
-		})
-	})
-
-	Describe("SetWithTTL", func() {
-		It("stores value that is retrievable before expiry", func() {
-			err := service.SetWithTTL(ctx, "ttl_key", []byte("ttl_value"), 3600)
-			Expect(err).ToNot(HaveOccurred())
-
-			value, exists, err := service.Get(ctx, "ttl_key")
-			Expect(err).ToNot(HaveOccurred())
-			Expect(exists).To(BeTrue())
-			Expect(value).To(Equal([]byte("ttl_value")))
-		})
-
-		It("value is not retrievable after expiry", func() {
-			// Insert a key with an already-expired TTL
-			_, err := service.db.Exec(`
-				INSERT INTO kvstore (key, value, size, expires_at)
-				VALUES ('short_ttl', 'gone_soon', 9, datetime('now', '-1 seconds'))
-			`)
-			Expect(err).ToNot(HaveOccurred())
-
-			_, exists, err := service.Get(ctx, "short_ttl")
-			Expect(err).ToNot(HaveOccurred())
-			Expect(exists).To(BeFalse())
-		})
-
-		It("rejects ttlSeconds <= 0", func() {
-			err := service.SetWithTTL(ctx, "bad_ttl", []byte("value"), 0)
-			Expect(err).To(HaveOccurred())
-			Expect(err.Error()).To(ContainSubstring("ttlSeconds must be greater than 0"))
-
-			err = service.SetWithTTL(ctx, "bad_ttl", []byte("value"), -5)
-			Expect(err).To(HaveOccurred())
-			Expect(err.Error()).To(ContainSubstring("ttlSeconds must be greater than 0"))
-		})
-
-		It("validates key same as Set", func() {
-			err := service.SetWithTTL(ctx, "", []byte("value"), 60)
-			Expect(err).To(HaveOccurred())
-			Expect(err.Error()).To(ContainSubstring("key cannot be empty"))
-		})
-
-		It("enforces size limits same as Set", func() {
-			bigValue := make([]byte, 2048)
-			err := service.SetWithTTL(ctx, "big_ttl", bigValue, 60)
-			Expect(err).To(HaveOccurred())
-			Expect(err.Error()).To(ContainSubstring("storage limit exceeded"))
-		})
-
-		It("overwrites existing key and updates TTL", func() {
-			// Insert a key with an already-expired TTL
-			_, err := service.db.Exec(`
-				INSERT INTO kvstore (key, value, size, expires_at)
-				VALUES ('overwrite_ttl', 'first', 5, datetime('now', '-1 seconds'))
-			`)
-			Expect(err).ToNot(HaveOccurred())
-
-			// Overwrite with a long TTL — should be retrievable
-			err = service.SetWithTTL(ctx, "overwrite_ttl", []byte("second"), 3600)
-			Expect(err).ToNot(HaveOccurred())
-
-			value, exists, err := service.Get(ctx, "overwrite_ttl")
-			Expect(err).ToNot(HaveOccurred())
-			Expect(exists).To(BeTrue())
-			Expect(value).To(Equal([]byte("second")))
-		})
-
-		It("tracks storage correctly", func() {
-			err := service.SetWithTTL(ctx, "sized_ttl", []byte("12345"), 3600)
-			Expect(err).ToNot(HaveOccurred())
-
-			used, err := service.GetStorageUsed(ctx)
-			Expect(err).ToNot(HaveOccurred())
-			Expect(used).To(Equal(int64(5)))
-		})
-	})
-
-	Describe("DeleteByPrefix", func() {
-		BeforeEach(func() {
-			Expect(service.Set(ctx, "cache:user:1", []byte("Alice"))).To(Succeed())
-			Expect(service.Set(ctx, "cache:user:2", []byte("Bob"))).To(Succeed())
-			Expect(service.Set(ctx, "cache:item:1", []byte("Widget"))).To(Succeed())
-			Expect(service.Set(ctx, "data:important", []byte("keep"))).To(Succeed())
-		})
-
-		It("deletes all keys with the given prefix", func() {
-			deleted, err := service.DeleteByPrefix(ctx, "cache:user:")
-			Expect(err).ToNot(HaveOccurred())
-			Expect(deleted).To(Equal(int64(2)))
-
-			keys, err := service.List(ctx, "")
-			Expect(err).ToNot(HaveOccurred())
-			Expect(keys).To(HaveLen(2))
-			Expect(keys).To(ContainElements("cache:item:1", "data:important"))
-		})
-
-		It("rejects empty prefix", func() {
-			_, err := service.DeleteByPrefix(ctx, "")
-			Expect(err).To(HaveOccurred())
-			Expect(err.Error()).To(ContainSubstring("prefix cannot be empty"))
-		})
-
-		It("returns 0 when no keys match", func() {
-			deleted, err := service.DeleteByPrefix(ctx, "nonexistent:")
-			Expect(err).ToNot(HaveOccurred())
-			Expect(deleted).To(Equal(int64(0)))
-		})
-
-		It("updates storage size correctly", func() {
-			usedBefore, _ := service.GetStorageUsed(ctx)
-			Expect(usedBefore).To(BeNumerically(">", 0))
-
-			_, err := service.DeleteByPrefix(ctx, "cache:")
-			Expect(err).ToNot(HaveOccurred())
-
-			usedAfter, _ := service.GetStorageUsed(ctx)
-			Expect(usedAfter).To(Equal(int64(4)))
-		})
-
-		It("handles special LIKE characters in prefix", func() {
-			Expect(service.Set(ctx, "test%special", []byte("v1"))).To(Succeed())
-			Expect(service.Set(ctx, "test_special", []byte("v2"))).To(Succeed())
-			Expect(service.Set(ctx, "testXspecial", []byte("v3"))).To(Succeed())
-
-			deleted, err := service.DeleteByPrefix(ctx, "test%")
-			Expect(err).ToNot(HaveOccurred())
-			Expect(deleted).To(Equal(int64(1)))
-
-			exists, _ := service.Has(ctx, "test_special")
-			Expect(exists).To(BeTrue())
-			exists, _ = service.Has(ctx, "testXspecial")
-			Expect(exists).To(BeTrue())
-		})
-
-		It("also deletes expired keys matching prefix", func() {
-			_, err := service.db.Exec(`
-				INSERT INTO kvstore (key, value, size, expires_at)
-				VALUES ('cache:expired', 'old', 3, datetime('now', '-1 seconds'))
-			`)
-			Expect(err).ToNot(HaveOccurred())
-
-			deleted, err := service.DeleteByPrefix(ctx, "cache:")
-			Expect(err).ToNot(HaveOccurred())
-			Expect(deleted).To(Equal(int64(4)))
-		})
-	})
-
-	Describe("GetMany", func() {
-		BeforeEach(func() {
-			Expect(service.Set(ctx, "key1", []byte("value1"))).To(Succeed())
-			Expect(service.Set(ctx, "key2", []byte("value2"))).To(Succeed())
-			Expect(service.Set(ctx, "key3", []byte("value3"))).To(Succeed())
-		})
-
-		It("retrieves multiple values at once", func() {
-			values, err := service.GetMany(ctx, []string{"key1", "key2", "key3"})
-			Expect(err).ToNot(HaveOccurred())
-			Expect(values).To(HaveLen(3))
-			Expect(values["key1"]).To(Equal([]byte("value1")))
-			Expect(values["key2"]).To(Equal([]byte("value2")))
-			Expect(values["key3"]).To(Equal([]byte("value3")))
-		})
-
-		It("omits missing keys from result", func() {
-			values, err := service.GetMany(ctx, []string{"key1", "missing", "key3"})
-			Expect(err).ToNot(HaveOccurred())
-			Expect(values).To(HaveLen(2))
-			Expect(values["key1"]).To(Equal([]byte("value1")))
-			Expect(values["key3"]).To(Equal([]byte("value3")))
-			_, hasMissing := values["missing"]
-			Expect(hasMissing).To(BeFalse())
-		})
-
-		It("returns empty map for empty keys slice", func() {
-			values, err := service.GetMany(ctx, []string{})
-			Expect(err).ToNot(HaveOccurred())
-			Expect(values).To(BeEmpty())
-		})
-
-		It("returns empty map for nil keys slice", func() {
-			values, err := service.GetMany(ctx, nil)
-			Expect(err).ToNot(HaveOccurred())
-			Expect(values).To(BeEmpty())
-		})
-
-		It("excludes expired keys", func() {
-			_, err := service.db.Exec(`
-				INSERT INTO kvstore (key, value, size, expires_at)
-				VALUES ('expired_many', 'old', 3, datetime('now', '-1 seconds'))
-			`)
-			Expect(err).ToNot(HaveOccurred())
-
-			values, err := service.GetMany(ctx, []string{"key1", "expired_many"})
-			Expect(err).ToNot(HaveOccurred())
-			Expect(values).To(HaveLen(1))
-			Expect(values["key1"]).To(Equal([]byte("value1")))
-		})
-
-		It("handles all keys missing", func() {
-			values, err := service.GetMany(ctx, []string{"nope1", "nope2"})
-			Expect(err).ToNot(HaveOccurred())
-			Expect(values).To(BeEmpty())
-		})
-	})
 })
 
 var _ = Describe("KVStoreService Integration", Ordered, func() {
@@ -720,21 +416,17 @@ var _ = Describe("KVStoreService Integration", Ordered, func() {
 
 	Describe("KVStore Operations via Plugin", func() {
 		type testKVStoreInput struct {
-			Operation  string   `json:"operation"`
-			Key        string   `json:"key"`
-			Value      []byte   `json:"value,omitempty"`
-			Prefix     string   `json:"prefix,omitempty"`
-			TTLSeconds int64    `json:"ttl_seconds,omitempty"`
-			Keys       []string `json:"keys,omitempty"`
+			Operation string `json:"operation"`
+			Key       string `json:"key"`
+			Value     []byte `json:"value,omitempty"`
+			Prefix    string `json:"prefix,omitempty"`
 		}
 		type testKVStoreOutput struct {
-			Value        []byte            `json:"value,omitempty"`
-			Values       map[string][]byte `json:"values,omitempty"`
-			Exists       bool              `json:"exists,omitempty"`
-			Keys         []string          `json:"keys,omitempty"`
-			StorageUsed  int64             `json:"storage_used,omitempty"`
-			DeletedCount int64             `json:"deleted_count,omitempty"`
-			Error        *string           `json:"error,omitempty"`
+			Value       []byte   `json:"value,omitempty"`
+			Exists      bool     `json:"exists,omitempty"`
+			Keys        []string `json:"keys,omitempty"`
+			StorageUsed int64    `json:"storage_used,omitempty"`
+			Error       *string  `json:"error,omitempty"`
 		}
 
 		callTestKVStore := func(ctx context.Context, input testKVStoreInput) (*testKVStoreOutput, error) {
@@ -902,107 +594,6 @@ var _ = Describe("KVStoreService Integration", Ordered, func() {
 			Expect(output.Exists).To(BeTrue())
 			Expect(output.Value).To(Equal(binaryData))
 		})
-
-		It("should set value with TTL and expire it", func() {
-			ctx := GinkgoT().Context()
-
-			// Set value with 1 second TTL
-			_, err := callTestKVStore(ctx, testKVStoreInput{
-				Operation:  "set_with_ttl",
-				Key:        "ttl_key",
-				Value:      []byte("temporary"),
-				TTLSeconds: 1,
-			})
-			Expect(err).ToNot(HaveOccurred())
-
-			// Immediately should exist
-			output, err := callTestKVStore(ctx, testKVStoreInput{
-				Operation: "get",
-				Key:       "ttl_key",
-			})
-			Expect(err).ToNot(HaveOccurred())
-			Expect(output.Exists).To(BeTrue())
-			Expect(output.Value).To(Equal([]byte("temporary")))
-
-			// Wait for expiration
-			time.Sleep(2 * time.Second)
-
-			// Should no longer exist
-			output, err = callTestKVStore(ctx, testKVStoreInput{
-				Operation: "get",
-				Key:       "ttl_key",
-			})
-			Expect(err).ToNot(HaveOccurred())
-			Expect(output.Exists).To(BeFalse())
-		})
-
-		It("should delete keys by prefix", func() {
-			ctx := GinkgoT().Context()
-
-			// Set multiple keys with shared prefix
-			for _, key := range []string{"del_prefix:a", "del_prefix:b", "keep:c"} {
-				_, err := callTestKVStore(ctx, testKVStoreInput{
-					Operation: "set",
-					Key:       key,
-					Value:     []byte("value"),
-				})
-				Expect(err).ToNot(HaveOccurred())
-			}
-
-			// Delete by prefix
-			output, err := callTestKVStore(ctx, testKVStoreInput{
-				Operation: "delete_by_prefix",
-				Prefix:    "del_prefix:",
-			})
-			Expect(err).ToNot(HaveOccurred())
-			Expect(output.DeletedCount).To(Equal(int64(2)))
-
-			// Verify remaining key
-			getOutput, err := callTestKVStore(ctx, testKVStoreInput{
-				Operation: "has",
-				Key:       "keep:c",
-			})
-			Expect(err).ToNot(HaveOccurred())
-			Expect(getOutput.Exists).To(BeTrue())
-
-			// Verify deleted keys are gone
-			getOutput, err = callTestKVStore(ctx, testKVStoreInput{
-				Operation: "has",
-				Key:       "del_prefix:a",
-			})
-			Expect(err).ToNot(HaveOccurred())
-			Expect(getOutput.Exists).To(BeFalse())
-		})
-
-		It("should get many values at once", func() {
-			ctx := GinkgoT().Context()
-
-			// Set multiple keys
-			for _, kv := range []struct{ k, v string }{
-				{"many:1", "val1"},
-				{"many:2", "val2"},
-				{"many:3", "val3"},
-			} {
-				_, err := callTestKVStore(ctx, testKVStoreInput{
-					Operation: "set",
-					Key:       kv.k,
-					Value:     []byte(kv.v),
-				})
-				Expect(err).ToNot(HaveOccurred())
-			}
-
-			// Get many, including a missing key
-			output, err := callTestKVStore(ctx, testKVStoreInput{
-				Operation: "get_many",
-				Keys:      []string{"many:1", "many:3", "many:missing"},
-			})
-			Expect(err).ToNot(HaveOccurred())
-			Expect(output.Values).To(HaveLen(2))
-			Expect(output.Values["many:1"]).To(Equal([]byte("val1")))
-			Expect(output.Values["many:3"]).To(Equal([]byte("val3")))
-			_, hasMissing := output.Values["many:missing"]
-			Expect(hasMissing).To(BeFalse())
-		})
 	})
 
 	Describe("Database Isolation", func() {

plugins/lyrics_adapter.go

@@ -0,0 +1,55 @@
+package plugins
+
+import (
+	"context"
+
+	"github.com/navidrome/navidrome/log"
+	"github.com/navidrome/navidrome/model"
+	"github.com/navidrome/navidrome/plugins/capabilities"
+)
+
+const CapabilityLyrics Capability = "Lyrics"
+
+const (
+	FuncLyricsGetLyrics = "nd_lyrics_get_lyrics"
+)
+
+func init() {
+	registerCapability(
+		CapabilityLyrics,
+		FuncLyricsGetLyrics,
+	)
+}
+
+// LyricsPlugin adapts a WASM plugin with the Lyrics capability.
+type LyricsPlugin struct {
+	name   string
+	plugin *plugin
+}
+
+// GetLyrics calls the plugin to fetch lyrics, then parses the raw text responses
+// using model.ToLyrics.
+func (l *LyricsPlugin) GetLyrics(ctx context.Context, mf *model.MediaFile) (model.LyricList, error) {
+	req := capabilities.GetLyricsRequest{
+		Track: mediaFileToTrackInfo(mf),
+	}
+	resp, err := callPluginFunction[capabilities.GetLyricsRequest, capabilities.GetLyricsResponse](
+		ctx, l.plugin, FuncLyricsGetLyrics, req,
+	)
+	if err != nil {
+		return nil, err
+	}
+
+	var result model.LyricList
+	for _, lt := range resp.Lyrics {
+		parsed, err := model.ToLyrics(lt.Lang, lt.Text)
+		if err != nil {
+			log.Warn(ctx, "Error parsing plugin lyrics", "plugin", l.name, err)
+			continue
+		}
+		if parsed != nil && !parsed.IsEmpty() {
+			result = append(result, *parsed)
+		}
+	}
+	return result, nil
+}

plugins/lyrics_adapter_test.go

@@ -0,0 +1,84 @@
+//go:build !windows
+
+package plugins
+
+import (
+	"github.com/navidrome/navidrome/model"
+	. "github.com/onsi/ginkgo/v2"
+	. "github.com/onsi/gomega"
+)
+
+var _ = Describe("LyricsPlugin", Ordered, func() {
+	var (
+		lyricsManager *Manager
+		provider      *LyricsPlugin
+	)
+
+	BeforeAll(func() {
+		lyricsManager, _ = createTestManagerWithPlugins(nil,
+			"test-lyrics"+PackageExtension,
+			"test-metadata-agent"+PackageExtension,
+		)
+
+		p, ok := lyricsManager.LoadLyricsProvider("test-lyrics")
+		Expect(ok).To(BeTrue())
+		provider = p.(*LyricsPlugin)
+	})
+
+	Describe("LoadLyricsProvider", func() {
+		It("returns a lyrics provider for a plugin with Lyrics capability", func() {
+			Expect(provider).ToNot(BeNil())
+		})
+
+		It("returns false for a plugin without Lyrics capability", func() {
+			_, ok := lyricsManager.LoadLyricsProvider("test-metadata-agent")
+			Expect(ok).To(BeFalse())
+		})
+
+		It("returns false for non-existent plugin", func() {
+			_, ok := lyricsManager.LoadLyricsProvider("non-existent")
+			Expect(ok).To(BeFalse())
+		})
+	})
+
+	Describe("GetLyrics", func() {
+		It("successfully returns lyrics from the plugin", func() {
+			track := &model.MediaFile{
+				ID:     "track-1",
+				Title:  "Test Song",
+				Artist: "Test Artist",
+			}
+
+			result, err := provider.GetLyrics(GinkgoT().Context(), track)
+			Expect(err).ToNot(HaveOccurred())
+			Expect(result).To(HaveLen(1))
+			Expect(result[0].Line).ToNot(BeEmpty())
+			Expect(result[0].Line[0].Value).To(ContainSubstring("Test Song"))
+		})
+
+		It("returns error when plugin returns error", func() {
+			manager, _ := createTestManagerWithPlugins(map[string]map[string]string{
+				"test-lyrics": {"error": "service unavailable"},
+			}, "test-lyrics"+PackageExtension)
+
+			p, ok := manager.LoadLyricsProvider("test-lyrics")
+			Expect(ok).To(BeTrue())
+
+			track := &model.MediaFile{ID: "track-1", Title: "Test Song"}
+			_, err := p.GetLyrics(GinkgoT().Context(), track)
+			Expect(err).To(HaveOccurred())
+		})
+	})
+
+	Describe("PluginNames", func() {
+		It("returns plugin names with Lyrics capability", func() {
+			names := lyricsManager.PluginNames("Lyrics")
+			Expect(names).To(ContainElement("test-lyrics"))
+		})
+
+		It("does not return metadata agent plugins for Lyrics capability", func() {
+			names := lyricsManager.PluginNames("Lyrics")
+			Expect(names).ToNot(ContainElement("test-metadata-agent"))
+		})
+	})
+})

plugins/manager.go

@@ -16,6 +16,7 @@ import (
 	extism "github.com/extism/go-sdk"
 	"github.com/navidrome/navidrome/conf"
 	"github.com/navidrome/navidrome/core/agents"
+	"github.com/navidrome/navidrome/core/lyrics"
 	"github.com/navidrome/navidrome/core/scrobbler"
 	"github.com/navidrome/navidrome/log"
 	"github.com/navidrome/navidrome/model"
@@ -276,6 +277,22 @@ func (m *Manager) LoadScrobbler(name string) (scrobbler.Scrobbler, bool) {
 	}, true
 }
 
+// LoadLyricsProvider loads and returns a lyrics provider plugin by name.
+func (m *Manager) LoadLyricsProvider(name string) (lyrics.Lyrics, bool) {
+	m.mu.RLock()
+	plugin, ok := m.plugins[name]
+	m.mu.RUnlock()
+
+	if !ok || !hasCapability(plugin.capabilities, CapabilityLyrics) {
+		return nil, false
+	}
+
+	return &LyricsPlugin{
+		name:   plugin.name,
+		plugin: plugin,
+	}, true
+}
+
 // PluginInfo contains basic information about a plugin for metrics/insights.
 type PluginInfo struct {
 	Name    string

plugins/manager_loader.go

@@ -103,7 +103,7 @@ var hostServices = []hostServiceEntry{
 		hasPermission: func(p *Permissions) bool { return p != nil && p.Kvstore != nil },
 		create: func(ctx *serviceContext) ([]extism.HostFunction, io.Closer) {
 			perm := ctx.permissions.Kvstore
-			service, err := newKVStoreService(ctx.manager.ctx, ctx.pluginName, perm)
+			service, err := newKVStoreService(ctx.pluginName, perm)
 			if err != nil {
 				log.Error("Failed to create KVStore service", "plugin", ctx.pluginName, err)
 				return nil, nil

plugins/migrate.go

@@ -1,47 +0,0 @@
-package plugins
-
-import (
-	"database/sql"
-	"fmt"
-)
-
-// migrateDB applies schema migrations to a SQLite database.
-//
-// Each entry in migrations is a single SQL statement. The current schema version
-// is tracked using SQLite's built-in PRAGMA user_version. Only statements after
-// the current version are executed, within a single transaction.
-func migrateDB(db *sql.DB, migrations []string) error {
-	var version int
-	if err := db.QueryRow(`PRAGMA user_version`).Scan(&version); err != nil {
-		return fmt.Errorf("reading schema version: %w", err)
-	}
-
-	if version >= len(migrations) {
-		return nil
-	}
-
-	tx, err := db.Begin()
-	if err != nil {
-		return fmt.Errorf("starting migration transaction: %w", err)
-	}
-	defer func() { _ = tx.Rollback() }()
-
-	for i := version; i < len(migrations); i++ {
-		if _, err := tx.Exec(migrations[i]); err != nil {
-			return fmt.Errorf("migration %d failed: %w", i+1, err)
-		}
-	}
-
-	// PRAGMA statements cannot be executed inside a transaction in some SQLite
-	// drivers, but with mattn/go-sqlite3 this works. We set it inside the tx
-	// so that a failed commit leaves the version unchanged.
-	if _, err := tx.Exec(fmt.Sprintf(`PRAGMA user_version = %d`, len(migrations))); err != nil {
-		return fmt.Errorf("updating schema version: %w", err)
-	}
-
-	if err := tx.Commit(); err != nil {
-		return fmt.Errorf("committing migrations: %w", err)
-	}
-
-	return nil
-}

plugins/migrate_test.go

@@ -1,99 +0,0 @@
-//go:build !windows
-
-package plugins
-
-import (
-	"database/sql"
-
-	_ "github.com/mattn/go-sqlite3"
-	. "github.com/onsi/ginkgo/v2"
-	. "github.com/onsi/gomega"
-)
-
-var _ = Describe("migrateDB", func() {
-	var db *sql.DB
-
-	BeforeEach(func() {
-		var err error
-		db, err = sql.Open("sqlite3", ":memory:")
-		Expect(err).ToNot(HaveOccurred())
-	})
-
-	AfterEach(func() {
-		if db != nil {
-			db.Close()
-		}
-	})
-
-	getUserVersion := func() int {
-		var version int
-		Expect(db.QueryRow(`PRAGMA user_version`).Scan(&version)).To(Succeed())
-		return version
-	}
-
-	It("applies all migrations on a fresh database", func() {
-		migrations := []string{
-			`CREATE TABLE test (id INTEGER PRIMARY KEY, name TEXT)`,
-			`ALTER TABLE test ADD COLUMN email TEXT`,
-		}
-
-		Expect(migrateDB(db, migrations)).To(Succeed())
-		Expect(getUserVersion()).To(Equal(2))
-
-		// Verify schema
-		_, err := db.Exec(`INSERT INTO test (id, name, email) VALUES (1, 'Alice', 'alice@test.com')`)
-		Expect(err).ToNot(HaveOccurred())
-	})
-
-	It("skips already applied migrations", func() {
-		migrations1 := []string{
-			`CREATE TABLE test (id INTEGER PRIMARY KEY, name TEXT)`,
-		}
-		Expect(migrateDB(db, migrations1)).To(Succeed())
-		Expect(getUserVersion()).To(Equal(1))
-
-		// Add a new migration
-		migrations2 := []string{
-			`CREATE TABLE test (id INTEGER PRIMARY KEY, name TEXT)`,
-			`ALTER TABLE test ADD COLUMN email TEXT`,
-		}
-		Expect(migrateDB(db, migrations2)).To(Succeed())
-		Expect(getUserVersion()).To(Equal(2))
-
-		// Verify the new column exists
-		_, err := db.Exec(`INSERT INTO test (id, name, email) VALUES (1, 'Alice', 'alice@test.com')`)
-		Expect(err).ToNot(HaveOccurred())
-	})
-
-	It("is a no-op when all migrations are applied", func() {
-		migrations := []string{
-			`CREATE TABLE test (id INTEGER PRIMARY KEY)`,
-		}
-		Expect(migrateDB(db, migrations)).To(Succeed())
-		Expect(migrateDB(db, migrations)).To(Succeed())
-		Expect(getUserVersion()).To(Equal(1))
-	})
-
-	It("is a no-op with empty migrations slice", func() {
-		Expect(migrateDB(db, nil)).To(Succeed())
-		Expect(getUserVersion()).To(Equal(0))
-	})
-
-	It("rolls back on failure", func() {
-		migrations := []string{
-			`CREATE TABLE test (id INTEGER PRIMARY KEY)`,
-			`INVALID SQL STATEMENT`,
-		}
-
-		err := migrateDB(db, migrations)
-		Expect(err).To(HaveOccurred())
-		Expect(err.Error()).To(ContainSubstring("migration 2 failed"))
-
-		// Version should remain 0 (rolled back)
-		Expect(getUserVersion()).To(Equal(0))
-
-		// Table should not exist (rolled back)
-		_, err = db.Exec(`INSERT INTO test (id) VALUES (1)`)
-		Expect(err).To(HaveOccurred())
-	})
-})

plugins/pdk/go/host/nd_host_kvstore.go

@@ -19,20 +19,15 @@ import (
 //go:wasmimport extism:host/user kvstore_set
 func kvstore_set(uint64) uint64
 
-// kvstore_setwithttl is the host function provided by Navidrome.
-//
-//go:wasmimport extism:host/user kvstore_setwithttl
-func kvstore_setwithttl(uint64) uint64
-
 // kvstore_get is the host function provided by Navidrome.
 //
 //go:wasmimport extism:host/user kvstore_get
 func kvstore_get(uint64) uint64
 
-// kvstore_getmany is the host function provided by Navidrome.
+// kvstore_delete is the host function provided by Navidrome.
 //
-//go:wasmimport extism:host/user kvstore_getmany
-func kvstore_getmany(uint64) uint64
+//go:wasmimport extism:host/user kvstore_delete
+func kvstore_delete(uint64) uint64
 
 // kvstore_has is the host function provided by Navidrome.
 //
@@ -44,16 +39,6 @@ func kvstore_has(uint64) uint64
 //go:wasmimport extism:host/user kvstore_list
 func kvstore_list(uint64) uint64
 
-// kvstore_delete is the host function provided by Navidrome.
-//
-//go:wasmimport extism:host/user kvstore_delete
-func kvstore_delete(uint64) uint64
-
-// kvstore_deletebyprefix is the host function provided by Navidrome.
-//
-//go:wasmimport extism:host/user kvstore_deletebyprefix
-func kvstore_deletebyprefix(uint64) uint64
-
 // kvstore_getstorageused is the host function provided by Navidrome.
 //
 //go:wasmimport extism:host/user kvstore_getstorageused
@@ -64,12 +49,6 @@ type kVStoreSetRequest struct {
 	Value []byte `json:"value"`
 }
 
-type kVStoreSetWithTTLRequest struct {
-	Key        string `json:"key"`
-	Value      []byte `json:"value"`
-	TtlSeconds int64  `json:"ttlSeconds"`
-}
-
 type kVStoreGetRequest struct {
 	Key string `json:"key"`
 }
@@ -80,13 +59,8 @@ type kVStoreGetResponse struct {
 	Error  string `json:"error,omitempty"`
 }
 
-type kVStoreGetManyRequest struct {
-	Keys []string `json:"keys"`
-}
-
-type kVStoreGetManyResponse struct {
-	Values map[string][]byte `json:"values,omitempty"`
-	Error  string            `json:"error,omitempty"`
+type kVStoreDeleteRequest struct {
+	Key string `json:"key"`
 }
 
 type kVStoreHasRequest struct {
@@ -107,19 +81,6 @@ type kVStoreListResponse struct {
 	Error string   `json:"error,omitempty"`
 }
 
-type kVStoreDeleteRequest struct {
-	Key string `json:"key"`
-}
-
-type kVStoreDeleteByPrefixRequest struct {
-	Prefix string `json:"prefix"`
-}
-
-type kVStoreDeleteByPrefixResponse struct {
-	DeletedCount int64  `json:"deletedCount,omitempty"`
-	Error        string `json:"error,omitempty"`
-}
-
 type kVStoreGetStorageUsedResponse struct {
 	Bytes int64  `json:"bytes,omitempty"`
 	Error string `json:"error,omitempty"`
@@ -166,52 +127,6 @@ func KVStoreSet(key string, value []byte) error {
 	return nil
 }
 
-// KVStoreSetWithTTL calls the kvstore_setwithttl host function.
-// SetWithTTL stores a byte value with the given key and a time-to-live.
-//
-// After ttlSeconds, the key is treated as non-existent and will be
-// cleaned up lazily. ttlSeconds must be greater than 0.
-//
-// Parameters:
-//   - key: The storage key (max 256 bytes, UTF-8)
-//   - value: The byte slice to store
-//   - ttlSeconds: Time-to-live in seconds (must be > 0)
-//
-// Returns an error if the storage limit would be exceeded or the operation fails.
-func KVStoreSetWithTTL(key string, value []byte, ttlSeconds int64) error {
-	// Marshal request to JSON
-	req := kVStoreSetWithTTLRequest{
-		Key:        key,
-		Value:      value,
-		TtlSeconds: ttlSeconds,
-	}
-	reqBytes, err := json.Marshal(req)
-	if err != nil {
-		return err
-	}
-	reqMem := pdk.AllocateBytes(reqBytes)
-	defer reqMem.Free()
-
-	// Call the host function
-	responsePtr := kvstore_setwithttl(reqMem.Offset())
-
-	// Read the response from memory
-	responseMem := pdk.FindMemory(responsePtr)
-	responseBytes := responseMem.ReadBytes()
-
-	// Parse error-only response
-	var response struct {
-		Error string `json:"error,omitempty"`
-	}
-	if err := json.Unmarshal(responseBytes, &response); err != nil {
-		return err
-	}
-	if response.Error != "" {
-		return errors.New(response.Error)
-	}
-	return nil
-}
-
 // KVStoreGet calls the kvstore_get host function.
 // Get retrieves a byte value from storage.
 //
@@ -252,45 +167,43 @@ func KVStoreGet(key string) ([]byte, bool, error) {
 	return response.Value, response.Exists, nil
 }
 
-// KVStoreGetMany calls the kvstore_getmany host function.
-// GetMany retrieves multiple values in a single call.
+// KVStoreDelete calls the kvstore_delete host function.
+// Delete removes a value from storage.
 //
 // Parameters:
-//   - keys: The storage keys to retrieve
+//   - key: The storage key
 //
-// Returns a map of key to value for keys that exist and have not expired.
-// Missing or expired keys are omitted from the result.
-func KVStoreGetMany(keys []string) (map[string][]byte, error) {
+// Returns an error if the operation fails. Does not return an error if the key doesn't exist.
+func KVStoreDelete(key string) error {
 	// Marshal request to JSON
-	req := kVStoreGetManyRequest{
-		Keys: keys,
+	req := kVStoreDeleteRequest{
+		Key: key,
 	}
 	reqBytes, err := json.Marshal(req)
 	if err != nil {
-		return nil, err
+		return err
 	}
 	reqMem := pdk.AllocateBytes(reqBytes)
 	defer reqMem.Free()
 
 	// Call the host function
-	responsePtr := kvstore_getmany(reqMem.Offset())
+	responsePtr := kvstore_delete(reqMem.Offset())
 
 	// Read the response from memory
 	responseMem := pdk.FindMemory(responsePtr)
 	responseBytes := responseMem.ReadBytes()
 
-	// Parse the response
-	var response kVStoreGetManyResponse
+	// Parse error-only response
+	var response struct {
+		Error string `json:"error,omitempty"`
+	}
 	if err := json.Unmarshal(responseBytes, &response); err != nil {
-		return nil, err
+		return err
 	}
-
-	// Convert Error field to Go error
 	if response.Error != "" {
-		return nil, errors.New(response.Error)
+		return errors.New(response.Error)
 	}
-
-	return response.Values, nil
+	return nil
 }
 
 // KVStoreHas calls the kvstore_has host function.
@@ -373,85 +286,6 @@ func KVStoreList(prefix string) ([]string, error) {
 	return response.Keys, nil
 }
 
-// KVStoreDelete calls the kvstore_delete host function.
-// Delete removes a value from storage.
-//
-// Parameters:
-//   - key: The storage key
-//
-// Returns an error if the operation fails. Does not return an error if the key doesn't exist.
-func KVStoreDelete(key string) error {
-	// Marshal request to JSON
-	req := kVStoreDeleteRequest{
-		Key: key,
-	}
-	reqBytes, err := json.Marshal(req)
-	if err != nil {
-		return err
-	}
-	reqMem := pdk.AllocateBytes(reqBytes)
-	defer reqMem.Free()
-
-	// Call the host function
-	responsePtr := kvstore_delete(reqMem.Offset())
-
-	// Read the response from memory
-	responseMem := pdk.FindMemory(responsePtr)
-	responseBytes := responseMem.ReadBytes()
-
-	// Parse error-only response
-	var response struct {
-		Error string `json:"error,omitempty"`
-	}
-	if err := json.Unmarshal(responseBytes, &response); err != nil {
-		return err
-	}
-	if response.Error != "" {
-		return errors.New(response.Error)
-	}
-	return nil
-}
-
-// KVStoreDeleteByPrefix calls the kvstore_deletebyprefix host function.
-// DeleteByPrefix removes all keys matching the given prefix.
-//
-// Parameters:
-//   - prefix: Key prefix to match (must not be empty)
-//
-// Returns the number of keys deleted. Includes expired keys.
-func KVStoreDeleteByPrefix(prefix string) (int64, error) {
-	// Marshal request to JSON
-	req := kVStoreDeleteByPrefixRequest{
-		Prefix: prefix,
-	}
-	reqBytes, err := json.Marshal(req)
-	if err != nil {
-		return 0, err
-	}
-	reqMem := pdk.AllocateBytes(reqBytes)
-	defer reqMem.Free()
-
-	// Call the host function
-	responsePtr := kvstore_deletebyprefix(reqMem.Offset())
-
-	// Read the response from memory
-	responseMem := pdk.FindMemory(responsePtr)
-	responseBytes := responseMem.ReadBytes()
-
-	// Parse the response
-	var response kVStoreDeleteByPrefixResponse
-	if err := json.Unmarshal(responseBytes, &response); err != nil {
-		return 0, err
-	}
-
-	// Convert Error field to Go error
-	if response.Error != "" {
-		return 0, errors.New(response.Error)
-	}
-
-	return response.DeletedCount, nil
-}
-
 // KVStoreGetStorageUsed calls the kvstore_getstorageused host function.
 // GetStorageUsed returns the total storage used by this plugin in bytes.
 func KVStoreGetStorageUsed() (int64, error) {

plugins/pdk/go/host/nd_host_kvstore_stub.go

@@ -37,28 +37,6 @@ func KVStoreSet(key string, value []byte) error {
 	return KVStoreMock.Set(key, value)
 }
 
-// SetWithTTL is the mock method for KVStoreSetWithTTL.
-func (m *mockKVStoreService) SetWithTTL(key string, value []byte, ttlSeconds int64) error {
-	args := m.Called(key, value, ttlSeconds)
-	return args.Error(0)
-}
-
-// KVStoreSetWithTTL delegates to the mock instance.
-// SetWithTTL stores a byte value with the given key and a time-to-live.
-//
-// After ttlSeconds, the key is treated as non-existent and will be
-// cleaned up lazily. ttlSeconds must be greater than 0.
-//
-// Parameters:
-//   - key: The storage key (max 256 bytes, UTF-8)
-//   - value: The byte slice to store
-//   - ttlSeconds: Time-to-live in seconds (must be > 0)
-//
-// Returns an error if the storage limit would be exceeded or the operation fails.
-func KVStoreSetWithTTL(key string, value []byte, ttlSeconds int64) error {
-	return KVStoreMock.SetWithTTL(key, value, ttlSeconds)
-}
-
 // Get is the mock method for KVStoreGet.
 func (m *mockKVStoreService) Get(key string) ([]byte, bool, error) {
 	args := m.Called(key)
@@ -76,22 +54,21 @@ func KVStoreGet(key string) ([]byte, bool, error) {
 	return KVStoreMock.Get(key)
 }
 
-// GetMany is the mock method for KVStoreGetMany.
-func (m *mockKVStoreService) GetMany(keys []string) (map[string][]byte, error) {
-	args := m.Called(keys)
-	return args.Get(0).(map[string][]byte), args.Error(1)
+// Delete is the mock method for KVStoreDelete.
+func (m *mockKVStoreService) Delete(key string) error {
+	args := m.Called(key)
+	return args.Error(0)
 }
 
-// KVStoreGetMany delegates to the mock instance.
-// GetMany retrieves multiple values in a single call.
+// KVStoreDelete delegates to the mock instance.
+// Delete removes a value from storage.
 //
 // Parameters:
-//   - keys: The storage keys to retrieve
+//   - key: The storage key
 //
-// Returns a map of key to value for keys that exist and have not expired.
-// Missing or expired keys are omitted from the result.
-func KVStoreGetMany(keys []string) (map[string][]byte, error) {
-	return KVStoreMock.GetMany(keys)
+// Returns an error if the operation fails. Does not return an error if the key doesn't exist.
+func KVStoreDelete(key string) error {
+	return KVStoreMock.Delete(key)
 }
 
 // Has is the mock method for KVStoreHas.
@@ -128,40 +105,6 @@ func KVStoreList(prefix string) ([]string, error) {
 	return KVStoreMock.List(prefix)
 }
 
-// Delete is the mock method for KVStoreDelete.
-func (m *mockKVStoreService) Delete(key string) error {
-	args := m.Called(key)
-	return args.Error(0)
-}
-
-// KVStoreDelete delegates to the mock instance.
-// Delete removes a value from storage.
-//
-// Parameters:
-//   - key: The storage key
-//
-// Returns an error if the operation fails. Does not return an error if the key doesn't exist.
-func KVStoreDelete(key string) error {
-	return KVStoreMock.Delete(key)
-}
-
-// DeleteByPrefix is the mock method for KVStoreDeleteByPrefix.
-func (m *mockKVStoreService) DeleteByPrefix(prefix string) (int64, error) {
-	args := m.Called(prefix)
-	return args.Get(0).(int64), args.Error(1)
-}
-
-// KVStoreDeleteByPrefix delegates to the mock instance.
-// DeleteByPrefix removes all keys matching the given prefix.
-//
-// Parameters:
-//   - prefix: Key prefix to match (must not be empty)
-//
-// Returns the number of keys deleted. Includes expired keys.
-func KVStoreDeleteByPrefix(prefix string) (int64, error) {
-	return KVStoreMock.DeleteByPrefix(prefix)
-}
-
 // GetStorageUsed is the mock method for KVStoreGetStorageUsed.
 func (m *mockKVStoreService) GetStorageUsed() (int64, error) {
 	args := m.Called()

plugins/pdk/go/lyrics/lyrics.go

@@ -0,0 +1,118 @@
+// Code generated by ndpgen. DO NOT EDIT.
+//
+// This file contains export wrappers for the Lyrics capability.
+// It is intended for use in Navidrome plugins built with TinyGo.
+//
+//go:build wasip1
+
+package lyrics
+
+import (
+	"github.com/navidrome/navidrome/plugins/pdk/go/pdk"
+)
+
+// ArtistRef is a reference to an artist with name and optional MBID.
+type ArtistRef struct {
+	// ID is the internal Navidrome artist ID (if known).
+	ID string `json:"id,omitempty"`
+	// Name is the artist name.
+	Name string `json:"name"`
+	// MBID is the MusicBrainz ID for the artist.
+	MBID string `json:"mbid,omitempty"`
+}
+
+// GetLyricsRequest contains the track information for lyrics lookup.
+type GetLyricsRequest struct {
+	Track TrackInfo `json:"track"`
+}
+
+// GetLyricsResponse contains the lyrics returned by the plugin.
+type GetLyricsResponse struct {
+	Lyrics []LyricsText `json:"lyrics"`
+}
+
+// LyricsText represents a single set of lyrics in raw text format.
+// Text can be plain text or LRC format — Navidrome will parse it.
+type LyricsText struct {
+	Lang string `json:"lang,omitempty"`
+	Text string `json:"text"`
+}
+
+// TrackInfo contains track metadata for scrobbling.
+type TrackInfo struct {
+	// ID is the internal Navidrome track ID.
+	ID string `json:"id"`
+	// Title is the track title.
+	Title string `json:"title"`
+	// Album is the album name.
+	Album string `json:"album"`
+	// Artist is the formatted artist name for display (e.g., "Artist1 • Artist2").
+	Artist string `json:"artist"`
+	// AlbumArtist is the formatted album artist name for display.
+	AlbumArtist string `json:"albumArtist"`
+	// Artists is the list of track artists.
+	Artists []ArtistRef `json:"artists"`
+	// AlbumArtists is the list of album artists.
+	AlbumArtists []ArtistRef `json:"albumArtists"`
+	// Duration is the track duration in seconds.
+	Duration float32 `json:"duration"`
+	// TrackNumber is the track number on the album.
+	TrackNumber int32 `json:"trackNumber"`
+	// DiscNumber is the disc number.
+	DiscNumber int32 `json:"discNumber"`
+	// MBZRecordingID is the MusicBrainz recording ID.
+	MBZRecordingID string `json:"mbzRecordingId,omitempty"`
+	// MBZAlbumID is the MusicBrainz album/release ID.
+	MBZAlbumID string `json:"mbzAlbumId,omitempty"`
+	// MBZReleaseGroupID is the MusicBrainz release group ID.
+	MBZReleaseGroupID string `json:"mbzReleaseGroupId,omitempty"`
+	// MBZReleaseTrackID is the MusicBrainz release track ID.
+	MBZReleaseTrackID string `json:"mbzReleaseTrackId,omitempty"`
+}
+
+// Lyrics requires all methods to be implemented.
+// Lyrics provides lyrics for a given track from external sources.
+type Lyrics interface {
+	// GetLyrics
+	GetLyrics(GetLyricsRequest) (GetLyricsResponse, error)
+} // Internal implementation holders
+var (
+	lyricsImpl func(GetLyricsRequest) (GetLyricsResponse, error)
+)
+
+// Register registers a lyrics implementation.
+// All methods are required.
+func Register(impl Lyrics) {
+	lyricsImpl = impl.GetLyrics
+}
+
+// NotImplementedCode is the standard return code for unimplemented functions.
+// The host recognizes this and skips the plugin gracefully.
+const NotImplementedCode int32 = -2
+
+//go:wasmexport nd_lyrics_get_lyrics
+func _NdLyricsGetLyrics() int32 {
+	if lyricsImpl == nil {
+		// Return standard code - host will skip this plugin gracefully
+		return NotImplementedCode
+	}
+
+	var input GetLyricsRequest
+	if err := pdk.InputJSON(&input); err != nil {
+		pdk.SetError(err)
+		return -1
+	}
+
+	output, err := lyricsImpl(input)
+	if err != nil {
+		pdk.SetError(err)
+		return -1
+	}
+
+	if err := pdk.OutputJSON(output); err != nil {
+		pdk.SetError(err)
+		return -1
+	}
+
+	return 0
+}

plugins/pdk/go/lyrics/lyrics_stub.go

@@ -0,0 +1,82 @@
+// Code generated by ndpgen. DO NOT EDIT.
+//
+// This file provides stub implementations for non-WASM platforms.
+// It allows Go plugins to compile and run tests outside of WASM,
+// but the actual functionality is only available in WASM builds.
+//
+//go:build !wasip1
+
+package lyrics
+
+// ArtistRef is a reference to an artist with name and optional MBID.
+type ArtistRef struct {
+	// ID is the internal Navidrome artist ID (if known).
+	ID string `json:"id,omitempty"`
+	// Name is the artist name.
+	Name string `json:"name"`
+	// MBID is the MusicBrainz ID for the artist.
+	MBID string `json:"mbid,omitempty"`
+}
+
+// GetLyricsRequest contains the track information for lyrics lookup.
+type GetLyricsRequest struct {
+	Track TrackInfo `json:"track"`
+}
+
+// GetLyricsResponse contains the lyrics returned by the plugin.
+type GetLyricsResponse struct {
+	Lyrics []LyricsText `json:"lyrics"`
+}
+
+// LyricsText represents a single set of lyrics in raw text format.
+// Text can be plain text or LRC format — Navidrome will parse it.
+type LyricsText struct {
+	Lang string `json:"lang,omitempty"`
+	Text string `json:"text"`
+}
+
+// TrackInfo contains track metadata for scrobbling.
+type TrackInfo struct {
+	// ID is the internal Navidrome track ID.
+	ID string `json:"id"`
+	// Title is the track title.
+	Title string `json:"title"`
+	// Album is the album name.
+	Album string `json:"album"`
+	// Artist is the formatted artist name for display (e.g., "Artist1 • Artist2").
+	Artist string `json:"artist"`
+	// AlbumArtist is the formatted album artist name for display.
+	AlbumArtist string `json:"albumArtist"`
+	// Artists is the list of track artists.
+	Artists []ArtistRef `json:"artists"`
+	// AlbumArtists is the list of album artists.
+	AlbumArtists []ArtistRef `json:"albumArtists"`
+	// Duration is the track duration in seconds.
+	Duration float32 `json:"duration"`
+	// TrackNumber is the track number on the album.
+	TrackNumber int32 `json:"trackNumber"`
+	// DiscNumber is the disc number.
+	DiscNumber int32 `json:"discNumber"`
+	// MBZRecordingID is the MusicBrainz recording ID.
+	MBZRecordingID string `json:"mbzRecordingId,omitempty"`
+	// MBZAlbumID is the MusicBrainz album/release ID.
+	MBZAlbumID string `json:"mbzAlbumId,omitempty"`
+	// MBZReleaseGroupID is the MusicBrainz release group ID.
+	MBZReleaseGroupID string `json:"mbzReleaseGroupId,omitempty"`
+	// MBZReleaseTrackID is the MusicBrainz release track ID.
+	MBZReleaseTrackID string `json:"mbzReleaseTrackId,omitempty"`
+}
+
+// Lyrics requires all methods to be implemented.
+// Lyrics provides lyrics for a given track from external sources.
+type Lyrics interface {
+	// GetLyrics
+	GetLyrics(GetLyricsRequest) (GetLyricsResponse, error)
+}
+
+// NotImplementedCode is the standard return code for unimplemented functions.
+const NotImplementedCode int32 = -2
+
+// Register is a no-op on non-WASM platforms.
+// This stub allows code to compile outside of WASM.
+func Register(_ Lyrics) {}

plugins/pdk/python/host/nd_host_kvstore.py

@@ -26,20 +26,14 @@ def _kvstore_set(offset: int) -> int:
     ...
 
 
-@extism.import_fn("extism:host/user", "kvstore_setwithttl")
-def _kvstore_setwithttl(offset: int) -> int:
-    """Raw host function - do not call directly."""
-    ...
-
-
 @extism.import_fn("extism:host/user", "kvstore_get")
 def _kvstore_get(offset: int) -> int:
     """Raw host function - do not call directly."""
     ...
 
 
-@extism.import_fn("extism:host/user", "kvstore_getmany")
-def _kvstore_getmany(offset: int) -> int:
+@extism.import_fn("extism:host/user", "kvstore_delete")
+def _kvstore_delete(offset: int) -> int:
     """Raw host function - do not call directly."""
     ...
 
@@ -56,18 +50,6 @@ def _kvstore_list(offset: int) -> int:
     ...
 
 
-@extism.import_fn("extism:host/user", "kvstore_delete")
-def _kvstore_delete(offset: int) -> int:
-    """Raw host function - do not call directly."""
-    ...
-
-
-@extism.import_fn("extism:host/user", "kvstore_deletebyprefix")
-def _kvstore_deletebyprefix(offset: int) -> int:
-    """Raw host function - do not call directly."""
-    ...
-
-
 @extism.import_fn("extism:host/user", "kvstore_getstorageused")
 def _kvstore_getstorageused(offset: int) -> int:
     """Raw host function - do not call directly."""
@@ -112,43 +94,6 @@ Returns an error if the storage limit would be exceeded or the operation fails.
 
 
 
-def kvstore_set_with_ttl(key: str, value: bytes, ttl_seconds: int) -> None:
-    """SetWithTTL stores a byte value with the given key and a time-to-live.
-
-After ttlSeconds, the key is treated as non-existent and will be
-cleaned up lazily. ttlSeconds must be greater than 0.
-
-Parameters:
-  - key: The storage key (max 256 bytes, UTF-8)
-  - value: The byte slice to store
-  - ttlSeconds: Time-to-live in seconds (must be > 0)
-
-Returns an error if the storage limit would be exceeded or the operation fails.
-
-    Args:
-        key: str parameter.
-        value: bytes parameter.
-        ttl_seconds: int parameter.
-
-    Raises:
-        HostFunctionError: If the host function returns an error.
-    """
-    request = {
-        "key": key,
-        "value": base64.b64encode(value).decode("ascii"),
-        "ttlSeconds": ttl_seconds,
-    }
-    request_bytes = json.dumps(request).encode("utf-8")
-    request_mem = extism.memory.alloc(request_bytes)
-    response_offset = _kvstore_setwithttl(request_mem.offset)
-    response_mem = extism.memory.find(response_offset)
-    response = json.loads(extism.memory.string(response_mem))
-
-    if response.get("error"):
-        raise HostFunctionError(response["error"])
-
-
-
 def kvstore_get(key: str) -> KVStoreGetResult:
     """Get retrieves a byte value from storage.
 
@@ -184,37 +129,32 @@ Returns the value and whether the key exists.
     )
 
 
-def kvstore_get_many(keys: Any) -> Any:
-    """GetMany retrieves multiple values in a single call.
+def kvstore_delete(key: str) -> None:
+    """Delete removes a value from storage.
 
 Parameters:
-  - keys: The storage keys to retrieve
+  - key: The storage key
 
-Returns a map of key to value for keys that exist and have not expired.
-Missing or expired keys are omitted from the result.
+Returns an error if the operation fails. Does not return an error if the key doesn't exist.
 
     Args:
-        keys: Any parameter.
-
-    Returns:
-        Any: The result value.
+        key: str parameter.
 
     Raises:
         HostFunctionError: If the host function returns an error.
     """
     request = {
-        "keys": keys,
+        "key": key,
     }
     request_bytes = json.dumps(request).encode("utf-8")
     request_mem = extism.memory.alloc(request_bytes)
-    response_offset = _kvstore_getmany(request_mem.offset)
+    response_offset = _kvstore_delete(request_mem.offset)
     response_mem = extism.memory.find(response_offset)
     response = json.loads(extism.memory.string(response_mem))
 
     if response.get("error"):
         raise HostFunctionError(response["error"])
 
-    return response.get("values", None)
 
 
 def kvstore_has(key: str) -> bool:
@@ -281,66 +221,6 @@ Returns a slice of matching keys.
     return response.get("keys", None)
 
 
-def kvstore_delete(key: str) -> None:
-    """Delete removes a value from storage.
-
-Parameters:
-  - key: The storage key
-
-Returns an error if the operation fails. Does not return an error if the key doesn't exist.
-
-    Args:
-        key: str parameter.
-
-    Raises:
-        HostFunctionError: If the host function returns an error.
-    """
-    request = {
-        "key": key,
-    }
-    request_bytes = json.dumps(request).encode("utf-8")
-    request_mem = extism.memory.alloc(request_bytes)
-    response_offset = _kvstore_delete(request_mem.offset)
-    response_mem = extism.memory.find(response_offset)
-    response = json.loads(extism.memory.string(response_mem))
-
-    if response.get("error"):
-        raise HostFunctionError(response["error"])
-
-
-
-def kvstore_delete_by_prefix(prefix: str) -> int:
-    """DeleteByPrefix removes all keys matching the given prefix.
-
-Parameters:
-  - prefix: Key prefix to match (must not be empty)
-
-Returns the number of keys deleted. Includes expired keys.
-
-    Args:
-        prefix: str parameter.
-
-    Returns:
-        int: The result value.
-
-    Raises:
-        HostFunctionError: If the host function returns an error.
-    """
-    request = {
-        "prefix": prefix,
-    }
-    request_bytes = json.dumps(request).encode("utf-8")
-    request_mem = extism.memory.alloc(request_bytes)
-    response_offset = _kvstore_deletebyprefix(request_mem.offset)
-    response_mem = extism.memory.find(response_offset)
-    response = json.loads(extism.memory.string(response_mem))
-
-    if response.get("error"):
-        raise HostFunctionError(response["error"])
-
-    return response.get("deletedCount", 0)
-
-
 def kvstore_get_storage_used() -> int:
     """GetStorageUsed returns the total storage used by this plugin in bytes.
 

plugins/pdk/rust/nd-pdk-capabilities/src/lib.rs

@@ -6,6 +6,7 @@
 //! for implementing Navidrome plugin capabilities in Rust.
 
 pub mod lifecycle;
+pub mod lyrics;
 pub mod metadata;
 pub mod scheduler;
 pub mod scrobbler;

plugins/pdk/rust/nd-pdk-capabilities/src/lyrics.rs

@@ -0,0 +1,148 @@
+// Code generated by ndpgen. DO NOT EDIT.
+//
+// This file contains export wrappers for the Lyrics capability.
+// It is intended for use in Navidrome plugins built with extism-pdk.
+
+use serde::{Deserialize, Serialize};
+
+// Helper functions for skip_serializing_if with numeric types
+#[allow(dead_code)]
+fn is_zero_i32(value: &i32) -> bool { *value == 0 }
+#[allow(dead_code)]
+fn is_zero_u32(value: &u32) -> bool { *value == 0 }
+#[allow(dead_code)]
+fn is_zero_i64(value: &i64) -> bool { *value == 0 }
+#[allow(dead_code)]
+fn is_zero_u64(value: &u64) -> bool { *value == 0 }
+#[allow(dead_code)]
+fn is_zero_f32(value: &f32) -> bool { *value == 0.0 }
+#[allow(dead_code)]
+fn is_zero_f64(value: &f64) -> bool { *value == 0.0 }
+/// ArtistRef is a reference to an artist with name and optional MBID.
+#[derive(Debug, Clone, Default, Serialize, Deserialize)]
+#[serde(rename_all = "camelCase")]
+pub struct ArtistRef {
+    /// ID is the internal Navidrome artist ID (if known).
+    #[serde(default, skip_serializing_if = "String::is_empty")]
+    pub id: String,
+    /// Name is the artist name.
+    #[serde(default)]
+    pub name: String,
+    /// MBID is the MusicBrainz ID for the artist.
+    #[serde(default, skip_serializing_if = "String::is_empty")]
+    pub mbid: String,
+}
+/// GetLyricsRequest contains the track information for lyrics lookup.
+#[derive(Debug, Clone, Default, Serialize, Deserialize)]
+#[serde(rename_all = "camelCase")]
+pub struct GetLyricsRequest {
+    #[serde(default)]
+    pub track: TrackInfo,
+}
+/// GetLyricsResponse contains the lyrics returned by the plugin.
+#[derive(Debug, Clone, Default, Serialize, Deserialize)]
+#[serde(rename_all = "camelCase")]
+pub struct GetLyricsResponse {
+    #[serde(default)]
+    pub lyrics: Vec<LyricsText>,
+}
+/// LyricsText represents a single set of lyrics in raw text format.
+/// Text can be plain text or LRC format — Navidrome will parse it.
+#[derive(Debug, Clone, Default, Serialize, Deserialize)]
+#[serde(rename_all = "camelCase")]
+pub struct LyricsText {
+    #[serde(default, skip_serializing_if = "String::is_empty")]
+    pub lang: String,
+    #[serde(default)]
+    pub text: String,
+}
+/// TrackInfo contains track metadata for scrobbling.
+#[derive(Debug, Clone, Default, Serialize, Deserialize)]
+#[serde(rename_all = "camelCase")]
+pub struct TrackInfo {
+    /// ID is the internal Navidrome track ID.
+    #[serde(default)]
+    pub id: String,
+    /// Title is the track title.
+    #[serde(default)]
+    pub title: String,
+    /// Album is the album name.
+    #[serde(default)]
+    pub album: String,
+    /// Artist is the formatted artist name for display (e.g., "Artist1 • Artist2").
+    #[serde(default)]
+    pub artist: String,
+    /// AlbumArtist is the formatted album artist name for display.
+    #[serde(default)]
+    pub album_artist: String,
+    /// Artists is the list of track artists.
+    #[serde(default)]
+    pub artists: Vec<ArtistRef>,
+    /// AlbumArtists is the list of album artists.
+    #[serde(default)]
+    pub album_artists: Vec<ArtistRef>,
+    /// Duration is the track duration in seconds.
+    #[serde(default)]
+    pub duration: f32,
+    /// TrackNumber is the track number on the album.
+    #[serde(default)]
+    pub track_number: i32,
+    /// DiscNumber is the disc number.
+    #[serde(default)]
+    pub disc_number: i32,
+    /// MBZRecordingID is the MusicBrainz recording ID.
+    #[serde(default, skip_serializing_if = "String::is_empty")]
+    pub mbz_recording_id: String,
+    /// MBZAlbumID is the MusicBrainz album/release ID.
+    #[serde(default, skip_serializing_if = "String::is_empty")]
+    pub mbz_album_id: String,
+    /// MBZReleaseGroupID is the MusicBrainz release group ID.
+    #[serde(default, skip_serializing_if = "String::is_empty")]
+    pub mbz_release_group_id: String,
+    /// MBZReleaseTrackID is the MusicBrainz release track ID.
+    #[serde(default, skip_serializing_if = "String::is_empty")]
+    pub mbz_release_track_id: String,
+}
+
+/// Error represents an error from a capability method.
+#[derive(Debug)]
+pub struct Error {
+    pub message: String,
+}
+
+impl std::fmt::Display for Error {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        write!(f, "{}", self.message)
+    }
+}
+
+impl std::error::Error for Error {}
+
+impl Error {
+    pub fn new(message: impl Into<String>) -> Self {
+        Self { message: message.into() }
+    }
+}
+
+/// Lyrics requires all methods to be implemented.
+/// Lyrics provides lyrics for a given track from external sources.
+pub trait Lyrics {
+    /// GetLyrics
+    fn get_lyrics(&self, req: GetLyricsRequest) -> Result<GetLyricsResponse, Error>;
+}
+
+/// Register all exports for the Lyrics capability.
+/// This macro generates the WASM export functions for all trait methods.
+#[macro_export]
+macro_rules! register_lyrics {
+    ($plugin_type:ty) => {
+        #[extism_pdk::plugin_fn]
+        pub fn nd_lyrics_get_lyrics(
+            req: extism_pdk::Json<$crate::lyrics::GetLyricsRequest>
+        ) -> extism_pdk::FnResult<extism_pdk::Json<$crate::lyrics::GetLyricsResponse>> {
+            let plugin = <$plugin_type>::default();
+            let result = $crate::lyrics::Lyrics::get_lyrics(&plugin, req.into_inner())?;
+            Ok(extism_pdk::Json(result))
+        }
+    };
+}

plugins/pdk/rust/nd-pdk-host/src/nd_host_kvstore.rs

@@ -44,22 +44,6 @@ struct KVStoreSetResponse {
     error: Option<String>,
 }
 
-#[derive(Debug, Clone, Serialize)]
-#[serde(rename_all = "camelCase")]
-struct KVStoreSetWithTTLRequest {
-    key: String,
-    #[serde(with = "base64_bytes")]
-    value: Vec<u8>,
-    ttl_seconds: i64,
-}
-
-#[derive(Debug, Clone, Deserialize)]
-#[serde(rename_all = "camelCase")]
-struct KVStoreSetWithTTLResponse {
-    #[serde(default)]
-    error: Option<String>,
-}
-
 #[derive(Debug, Clone, Serialize)]
 #[serde(rename_all = "camelCase")]
 struct KVStoreGetRequest {
@@ -80,15 +64,13 @@ struct KVStoreGetResponse {
 
 #[derive(Debug, Clone, Serialize)]
 #[serde(rename_all = "camelCase")]
-struct KVStoreGetManyRequest {
-    keys: Vec<String>,
+struct KVStoreDeleteRequest {
+    key: String,
 }
 
 #[derive(Debug, Clone, Deserialize)]
 #[serde(rename_all = "camelCase")]
-struct KVStoreGetManyResponse {
-    #[serde(default)]
-    values: std::collections::HashMap<String, Vec<u8>>,
+struct KVStoreDeleteResponse {
     #[serde(default)]
     error: Option<String>,
 }
@@ -123,34 +105,6 @@ struct KVStoreListResponse {
     error: Option<String>,
 }
 
-#[derive(Debug, Clone, Serialize)]
-#[serde(rename_all = "camelCase")]
-struct KVStoreDeleteRequest {
-    key: String,
-}
-
-#[derive(Debug, Clone, Deserialize)]
-#[serde(rename_all = "camelCase")]
-struct KVStoreDeleteResponse {
-    #[serde(default)]
-    error: Option<String>,
-}
-
-#[derive(Debug, Clone, Serialize)]
-#[serde(rename_all = "camelCase")]
-struct KVStoreDeleteByPrefixRequest {
-    prefix: String,
-}
-
-#[derive(Debug, Clone, Deserialize)]
-#[serde(rename_all = "camelCase")]
-struct KVStoreDeleteByPrefixResponse {
-    #[serde(default)]
-    deleted_count: i64,
-    #[serde(default)]
-    error: Option<String>,
-}
-
 #[derive(Debug, Clone, Deserialize)]
 #[serde(rename_all = "camelCase")]
 struct KVStoreGetStorageUsedResponse {
@@ -163,13 +117,10 @@ struct KVStoreGetStorageUsedResponse {
 #[host_fn]
 extern "ExtismHost" {
     fn kvstore_set(input: Json<KVStoreSetRequest>) -> Json<KVStoreSetResponse>;
-    fn kvstore_setwithttl(input: Json<KVStoreSetWithTTLRequest>) -> Json<KVStoreSetWithTTLResponse>;
     fn kvstore_get(input: Json<KVStoreGetRequest>) -> Json<KVStoreGetResponse>;
-    fn kvstore_getmany(input: Json<KVStoreGetManyRequest>) -> Json<KVStoreGetManyResponse>;
+    fn kvstore_delete(input: Json<KVStoreDeleteRequest>) -> Json<KVStoreDeleteResponse>;
     fn kvstore_has(input: Json<KVStoreHasRequest>) -> Json<KVStoreHasResponse>;
     fn kvstore_list(input: Json<KVStoreListRequest>) -> Json<KVStoreListResponse>;
-    fn kvstore_delete(input: Json<KVStoreDeleteRequest>) -> Json<KVStoreDeleteResponse>;
-    fn kvstore_deletebyprefix(input: Json<KVStoreDeleteByPrefixRequest>) -> Json<KVStoreDeleteByPrefixResponse>;
     fn kvstore_getstorageused(input: Json<serde_json::Value>) -> Json<KVStoreGetStorageUsedResponse>;
 }
 
@@ -202,41 +153,6 @@ pub fn set(key: &str, value: Vec<u8>) -> Result<(), Error> {
     Ok(())
 }
 
-/// SetWithTTL stores a byte value with the given key and a time-to-live.
-/// 
-/// After ttlSeconds, the key is treated as non-existent and will be
-/// cleaned up lazily. ttlSeconds must be greater than 0.
-/// 
-/// Parameters:
-///   - key: The storage key (max 256 bytes, UTF-8)
-///   - value: The byte slice to store
-///   - ttlSeconds: Time-to-live in seconds (must be > 0)
-/// 
-/// Returns an error if the storage limit would be exceeded or the operation fails.
-///
-/// # Arguments
-/// * `key` - String parameter.
-/// * `value` - Vec<u8> parameter.
-/// * `ttl_seconds` - i64 parameter.
-///
-/// # Errors
-/// Returns an error if the host function call fails.
-pub fn set_with_ttl(key: &str, value: Vec<u8>, ttl_seconds: i64) -> Result<(), Error> {
-    let response = unsafe {
-        kvstore_setwithttl(Json(KVStoreSetWithTTLRequest {
-            key: key.to_owned(),
-            value: value,
-            ttl_seconds: ttl_seconds,
-        }))?
-    };
-
-    if let Some(err) = response.0.error {
-        return Err(Error::msg(err));
-    }
-
-    Ok(())
-}
-
 /// Get retrieves a byte value from storage.
 /// 
 /// Parameters:
@@ -270,26 +186,22 @@ pub fn get(key: &str) -> Result<Option<Vec<u8>>, Error> {
     }
 }
 
-/// GetMany retrieves multiple values in a single call.
+/// Delete removes a value from storage.
 /// 
 /// Parameters:
-///   - keys: The storage keys to retrieve
+///   - key: The storage key
 /// 
-/// Returns a map of key to value for keys that exist and have not expired.
-/// Missing or expired keys are omitted from the result.
+/// Returns an error if the operation fails. Does not return an error if the key doesn't exist.
 ///
 /// # Arguments
-/// * `keys` - Vec<String> parameter.
-///
-/// # Returns
-/// The values value.
+/// * `key` - String parameter.
 ///
 /// # Errors
 /// Returns an error if the host function call fails.
-pub fn get_many(keys: Vec<String>) -> Result<std::collections::HashMap<String, Vec<u8>>, Error> {
+pub fn delete(key: &str) -> Result<(), Error> {
     let response = unsafe {
-        kvstore_getmany(Json(KVStoreGetManyRequest {
-            keys: keys,
+        kvstore_delete(Json(KVStoreDeleteRequest {
+            key: key.to_owned(),
         }))?
     };
 
@@ -297,7 +209,7 @@ pub fn get_many(keys: Vec<String>) -> Result<std::collections::HashMap<String, V
         return Err(Error::msg(err));
     }
 
-    Ok(response.0.values)
+    Ok(())
 }
 
 /// Has checks if a key exists in storage.
@@ -358,61 +270,6 @@ pub fn list(prefix: &str) -> Result<Vec<String>, Error> {
     Ok(response.0.keys)
 }
 
-/// Delete removes a value from storage.
-/// 
-/// Parameters:
-///   - key: The storage key
-/// 
-/// Returns an error if the operation fails. Does not return an error if the key doesn't exist.
-///
-/// # Arguments
-/// * `key` - String parameter.
-///
-/// # Errors
-/// Returns an error if the host function call fails.
-pub fn delete(key: &str) -> Result<(), Error> {
-    let response = unsafe {
-        kvstore_delete(Json(KVStoreDeleteRequest {
-            key: key.to_owned(),
-        }))?
-    };
-
-    if let Some(err) = response.0.error {
-        return Err(Error::msg(err));
-    }
-
-    Ok(())
-}
-
-/// DeleteByPrefix removes all keys matching the given prefix.
-/// 
-/// Parameters:
-///   - prefix: Key prefix to match (must not be empty)
-/// 
-/// Returns the number of keys deleted. Includes expired keys.
-///
-/// # Arguments
-/// * `prefix` - String parameter.
-///
-/// # Returns
-/// The deleted_count value.
-///
-/// # Errors
-/// Returns an error if the host function call fails.
-pub fn delete_by_prefix(prefix: &str) -> Result<i64, Error> {
-    let response = unsafe {
-        kvstore_deletebyprefix(Json(KVStoreDeleteByPrefixRequest {
-            prefix: prefix.to_owned(),
-        }))?
-    };
-
-    if let Some(err) = response.0.error {
-        return Err(Error::msg(err));
-    }
-
-    Ok(response.0.deleted_count)
-}
-
 /// GetStorageUsed returns the total storage used by this plugin in bytes.
 ///
 /// # Returns

plugins/testdata/test-kvstore/main.go

@@ -9,23 +9,19 @@ import (
 
 // TestKVStoreInput is the input for nd_test_kvstore callback.
 type TestKVStoreInput struct {
-	Operation  string   `json:"operation"`             // "set", "get", "delete", "has", "list", "get_storage_used", "set_with_ttl", "delete_by_prefix", "get_many"
-	Key        string   `json:"key"`                   // Storage key
-	Value      []byte   `json:"value"`                 // For set operations
-	Prefix     string   `json:"prefix"`                // For list/delete_by_prefix operations
-	TTLSeconds int64    `json:"ttl_seconds,omitempty"` // For set_with_ttl
-	Keys       []string `json:"keys,omitempty"`        // For get_many
+	Operation string `json:"operation"` // "set", "get", "delete", "has", "list", "get_storage_used"
+	Key       string `json:"key"`       // Storage key
+	Value     []byte `json:"value"`     // For set operations
+	Prefix    string `json:"prefix"`    // For list operation
 }
 
 // TestKVStoreOutput is the output from nd_test_kvstore callback.
 type TestKVStoreOutput struct {
-	Value        []byte            `json:"value,omitempty"`
-	Values       map[string][]byte `json:"values,omitempty"`
-	Exists       bool              `json:"exists,omitempty"`
-	Keys         []string          `json:"keys,omitempty"`
-	StorageUsed  int64             `json:"storage_used,omitempty"`
-	DeletedCount int64             `json:"deleted_count,omitempty"`
-	Error        *string           `json:"error,omitempty"`
+	Value       []byte   `json:"value,omitempty"`
+	Exists      bool     `json:"exists,omitempty"`
+	Keys        []string `json:"keys,omitempty"`
+	StorageUsed int64    `json:"storage_used,omitempty"`
+	Error       *string  `json:"error,omitempty"`
 }
 
 // nd_test_kvstore is the test callback that tests the kvstore host functions.
@@ -100,36 +96,6 @@ func ndTestKVStore() int32 {
 		pdk.OutputJSON(TestKVStoreOutput{StorageUsed: bytesUsed})
 		return 0
 
-	case "set_with_ttl":
-		err := host.KVStoreSetWithTTL(input.Key, input.Value, input.TTLSeconds)
-		if err != nil {
-			errStr := err.Error()
-			pdk.OutputJSON(TestKVStoreOutput{Error: &errStr})
-			return 0
-		}
-		pdk.OutputJSON(TestKVStoreOutput{})
-		return 0
-
-	case "delete_by_prefix":
-		deletedCount, err := host.KVStoreDeleteByPrefix(input.Prefix)
-		if err != nil {
-			errStr := err.Error()
-			pdk.OutputJSON(TestKVStoreOutput{Error: &errStr})
-			return 0
-		}
-		pdk.OutputJSON(TestKVStoreOutput{DeletedCount: deletedCount})
-		return 0
-
-	case "get_many":
-		values, err := host.KVStoreGetMany(input.Keys)
-		if err != nil {
-			errStr := err.Error()
-			pdk.OutputJSON(TestKVStoreOutput{Error: &errStr})
-			return 0
-		}
-		pdk.OutputJSON(TestKVStoreOutput{Values: values})
-		return 0
-
 	default:
 		errStr := "unknown operation: " + input.Operation
 		pdk.OutputJSON(TestKVStoreOutput{Error: &errStr})

plugins/testdata/test-lyrics/go.mod

@@ -0,0 +1,16 @@
+module test-lyrics
+
+go 1.25
+
+require github.com/navidrome/navidrome/plugins/pdk/go v0.0.0
+
+require (
+	github.com/davecgh/go-spew v1.1.1 // indirect
+	github.com/extism/go-pdk v1.1.3 // indirect
+	github.com/pmezard/go-difflib v1.0.0 // indirect
+	github.com/stretchr/objx v0.5.2 // indirect
+	github.com/stretchr/testify v1.11.1 // indirect
+	gopkg.in/yaml.v3 v3.0.1 // indirect
+)
+
+replace github.com/navidrome/navidrome/plugins/pdk/go => ../../pdk/go

plugins/testdata/test-lyrics/go.sum

@@ -0,0 +1,14 @@
+github.com/davecgh/go-spew v1.1.1 h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c=
+github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
+github.com/extism/go-pdk v1.1.3 h1:hfViMPWrqjN6u67cIYRALZTZLk/enSPpNKa+rZ9X2SQ=
+github.com/extism/go-pdk v1.1.3/go.mod h1:Gz+LIU/YCKnKXhgge8yo5Yu1F/lbv7KtKFkiCSzW/P4=
+github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=
+github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
+github.com/stretchr/objx v0.5.2 h1:xuMeJ0Sdp5ZMRXx/aWO6RZxdr3beISkG5/G/aIRr3pY=
+github.com/stretchr/objx v0.5.2/go.mod h1:FRsXN1f5AsAjCGJKqEizvkpNtU+EGNCLh3NxZ/8L+MA=
+github.com/stretchr/testify v1.11.1 h1:7s2iGBzp5EwR7/aIZr8ao5+dra3wiQyKjjFuvgVKu7U=
+github.com/stretchr/testify v1.11.1/go.mod h1:wZwfW3scLgRK+23gO65QZefKpKQRnfz6sD981Nm4B6U=
+gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405 h1:yhCVgyC4o1eVCa2tZl7eS0r+SDo693bJlVdllGtEeKM=
+gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
+gopkg.in/yaml.v3 v3.0.1 h1:fxVm/GzAzEWqLHuvctI91KS9hhNmmWOoWu0XTYJS7CA=
+gopkg.in/yaml.v3 v3.0.1/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=

plugins/testdata/test-lyrics/main.go

@@ -0,0 +1,35 @@
+// Test lyrics plugin for Navidrome plugin system integration tests.
+package main
+
+import (
+	"fmt"
+
+	"github.com/navidrome/navidrome/plugins/pdk/go/lyrics"
+	"github.com/navidrome/navidrome/plugins/pdk/go/pdk"
+)
+
+func init() {
+	lyrics.Register(&testLyrics{})
+}
+
+type testLyrics struct{}
+
+func (t *testLyrics) GetLyrics(input lyrics.GetLyricsRequest) (lyrics.GetLyricsResponse, error) {
+	// Check for configured error
+	errMsg, hasErr := pdk.GetConfig("error")
+	if hasErr && errMsg != "" {
+		return lyrics.GetLyricsResponse{}, fmt.Errorf("%s", errMsg)
+	}
+
+	// Return test lyrics based on track info
+	return lyrics.GetLyricsResponse{
+		Lyrics: []lyrics.LyricsText{
+			{
+				Lang: "eng",
+				Text: "Test lyrics for " + input.Track.Title + "\nBy " + input.Track.Artist,
+			},
+		},
+	}, nil
+}
+
+func main() {}

plugins/testdata/test-lyrics/manifest.json

@@ -0,0 +1,6 @@
+{
+  "name": "Test Lyrics",
+  "author": "Navidrome Test",
+  "version": "1.0.0",
+  "description": "A test lyrics plugin for integration testing"
+}

server/e2e/e2e_suite_test.go

@@ -19,6 +19,7 @@ import (
 	"github.com/navidrome/navidrome/core/artwork"
 	"github.com/navidrome/navidrome/core/auth"
 	"github.com/navidrome/navidrome/core/external"
+	"github.com/navidrome/navidrome/core/lyrics"
 	"github.com/navidrome/navidrome/core/metrics"
 	"github.com/navidrome/navidrome/core/playback"
 	"github.com/navidrome/navidrome/core/playlists"
@@ -396,6 +397,7 @@ func setupTestDB() {
 		core.NewShare(ds),
 		playback.PlaybackServer(nil),
 		metrics.NewNoopInstance(),
+		lyrics.NewLyrics(nil),
 	)
 }
 

server/subsonic/album_lists_test.go

@@ -27,7 +27,7 @@ var _ = Describe("Album Lists", func() {
 		ds = &tests.MockDataStore{}
 		auth.Init(ds)
 		mockRepo = ds.Album(ctx).(*tests.MockAlbumRepo)
-		router = New(ds, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil)
+		router = New(ds, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil)
 		w = httptest.NewRecorder()
 	})
 

server/subsonic/api.go

@@ -14,6 +14,7 @@ import (
 	"github.com/navidrome/navidrome/core"
 	"github.com/navidrome/navidrome/core/artwork"
 	"github.com/navidrome/navidrome/core/external"
+	"github.com/navidrome/navidrome/core/lyrics"
 	"github.com/navidrome/navidrome/core/metrics"
 	"github.com/navidrome/navidrome/core/playback"
 	playlistsvc "github.com/navidrome/navidrome/core/playlists"
@@ -48,12 +49,13 @@ type Router struct {
 	share     core.Share
 	playback  playback.PlaybackServer
 	metrics   metrics.Metrics
+	lyrics    lyrics.Lyrics
 }
 
 func New(ds model.DataStore, artwork artwork.Artwork, streamer core.MediaStreamer, archiver core.Archiver,
 	players core.Players, provider external.Provider, scanner model.Scanner, broker events.Broker,
 	playlists playlistsvc.Playlists, scrobbler scrobbler.PlayTracker, share core.Share, playback playback.PlaybackServer,
-	metrics metrics.Metrics,
+	metrics metrics.Metrics, lyrics lyrics.Lyrics,
 ) *Router {
 	r := &Router{
 		ds:        ds,
@@ -69,6 +71,7 @@ func New(ds model.DataStore, artwork artwork.Artwork, streamer core.MediaStreame
 		share:     share,
 		playback:  playback,
 		metrics:   metrics,
+		lyrics:    lyrics,
 	}
 	r.Handler = r.routes()
 	return r

server/subsonic/media_annotation_test.go

@@ -27,7 +27,7 @@ var _ = Describe("MediaAnnotationController", func() {
 		ds = &tests.MockDataStore{}
 		playTracker = &fakePlayTracker{}
 		eventBroker = &fakeEventBroker{}
-		router = New(ds, nil, nil, nil, nil, nil, nil, eventBroker, nil, playTracker, nil, nil, nil)
+		router = New(ds, nil, nil, nil, nil, nil, nil, eventBroker, nil, playTracker, nil, nil, nil, nil)
 	})
 
 	Describe("Scrobble", func() {

server/subsonic/media_retrieval.go

@@ -10,7 +10,6 @@ import (
 
 	"github.com/navidrome/navidrome/conf"
 	"github.com/navidrome/navidrome/consts"
-	"github.com/navidrome/navidrome/core/lyrics"
 	"github.com/navidrome/navidrome/log"
 	"github.com/navidrome/navidrome/model"
 	"github.com/navidrome/navidrome/resources"
@@ -109,7 +108,7 @@ func (api *Router) GetLyrics(r *http.Request) (*responses.Subsonic, error) {
 		return response, nil
 	}
 
-	structuredLyrics, err := lyrics.GetLyrics(r.Context(), &mediaFiles[0])
+	structuredLyrics, err := api.lyrics.GetLyrics(r.Context(), &mediaFiles[0])
 	if err != nil {
 		return nil, err
 	}
@@ -142,7 +141,7 @@ func (api *Router) GetLyricsBySongId(r *http.Request) (*responses.Subsonic, erro
 		return nil, err
 	}
 
-	structuredLyrics, err := lyrics.GetLyrics(r.Context(), mediaFile)
+	structuredLyrics, err := api.lyrics.GetLyrics(r.Context(), mediaFile)
 	if err != nil {
 		return nil, err
 	}

server/subsonic/media_retrieval_test.go

@@ -14,6 +14,7 @@ import (
 	"github.com/navidrome/navidrome/conf"
 	"github.com/navidrome/navidrome/conf/configtest"
 	"github.com/navidrome/navidrome/core/artwork"
+	"github.com/navidrome/navidrome/core/lyrics"
 	"github.com/navidrome/navidrome/model"
 	"github.com/navidrome/navidrome/server/subsonic/responses"
 	"github.com/navidrome/navidrome/tests"
@@ -33,7 +34,7 @@ var _ = Describe("MediaRetrievalController", func() {
 			MockedMediaFile: mockRepo,
 		}
 		artwork = &fakeArtwork{data: "image data"}
-		router = New(ds, artwork, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil)
+		router = New(ds, artwork, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, lyrics.NewLyrics(nil))
 		w = httptest.NewRecorder()
 		DeferCleanup(configtest.SetupConfig())
 		conf.Server.LyricsPriority = "embedded,.lrc"

server/subsonic/opensubsonic_test.go

@@ -19,7 +19,7 @@ var _ = Describe("GetOpenSubsonicExtensions", func() {
 	)
 
 	BeforeEach(func() {
-		router = subsonic.New(nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil)
+		router = subsonic.New(nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil)
 		w = httptest.NewRecorder()
 		r = httptest.NewRequest("GET", "/getOpenSubsonicExtensions?f=json", nil)
 	})

server/subsonic/playlists_test.go

@@ -24,7 +24,7 @@ var _ = Describe("buildPlaylist", func() {
 
 	BeforeEach(func() {
 		ds = &tests.MockDataStore{}
-		router = New(ds, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil)
+		router = New(ds, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil)
 		ctx = context.Background()
 	})
 
@@ -224,7 +224,7 @@ var _ = Describe("UpdatePlaylist", func() {
 	BeforeEach(func() {
 		ds = &tests.MockDataStore{}
 		playlists = &fakePlaylists{}
-		router = New(ds, nil, nil, nil, nil, nil, nil, nil, playlists, nil, nil, nil, nil)
+		router = New(ds, nil, nil, nil, nil, nil, nil, nil, playlists, nil, nil, nil, nil, nil)
 	})
 
 	It("clears the comment when parameter is empty", func() {

server/subsonic/searching_test.go

@@ -21,7 +21,7 @@ var _ = Describe("Search", func() {
 		ds = &tests.MockDataStore{}
 		auth.Init(ds)
 
-		router = New(ds, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil)
+		router = New(ds, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil)
 
 		// Get references to the mock repositories so we can inspect their Options
 		mockAlbumRepo = ds.Album(nil).(*tests.MockAlbumRepo)