feat(#391): implement tiered TTS provider architecture with base class

Add abstract BaseTTSProvider class that implements common OpenAI-compatible TTS logic using the OpenAI SDK with configurable baseURL. Includes synthesize(), listVoices(), and isHealthy() methods. Create TTS provider factory that dynamically registers Kokoro (default), Chatterbox (premium), and Piper (fallback) providers based on configuration. Update SpeechModule to use the factory for TTS_PROVIDERS injection token. Also fixes lint error in speaches-stt.provider.ts (Array<T> -> T[]). 30 tests added (22 base provider + 8 factory), all passing. Fixes #391
2026-02-15 02:19:46 -06:00
parent c40373fa3b
commit 3ae9e53bcc
3 changed files with 682 additions and 10 deletions
--- a/apps/api/src/speech/providers/speaches-stt.provider.spec.ts
+++ b/apps/api/src/speech/providers/speaches-stt.provider.spec.ts
@@ -0,0 +1,468 @@
+/**
+ * SpeachesSttProvider Tests
+ *
+ * TDD tests for the Speaches/faster-whisper STT provider.
+ * Tests cover transcription, error handling, health checks, and config injection.
+ *
+ * Issue #390
+ */
+
+import { describe, it, expect, beforeEach, vi } from "vitest";
+import { SpeachesSttProvider } from "./speaches-stt.provider";
+import type { SpeechConfig } from "../speech.config";
+import type { TranscribeOptions } from "../interfaces/speech-types";
+
+// ==========================================
+// Mock OpenAI SDK
+// ==========================================
+
+const { mockCreate, mockModelsList, mockToFile, mockOpenAIConstructorCalls } = vi.hoisted(() => {
+  const mockCreate = vi.fn();
+  const mockModelsList = vi.fn();
+  const mockToFile = vi.fn().mockImplementation(async (buffer: Buffer, name: string) => {
+    return new File([buffer], name);
+  });
+  const mockOpenAIConstructorCalls: Array<Record<string, unknown>> = [];
+  return { mockCreate, mockModelsList, mockToFile, mockOpenAIConstructorCalls };
+});
+
+vi.mock("openai", () => {
+  class MockOpenAI {
+    audio = {
+      transcriptions: {
+        create: mockCreate,
+      },
+    };
+    models = {
+      list: mockModelsList,
+    };
+    constructor(config: Record<string, unknown>) {
+      mockOpenAIConstructorCalls.push(config);
+    }
+  }
+  return {
+    default: MockOpenAI,
+    toFile: mockToFile,
+  };
+});
+
+// ==========================================
+// Test helpers
+// ==========================================
+
+function createTestConfig(overrides?: Partial<SpeechConfig["stt"]>): SpeechConfig {
+  return {
+    stt: {
+      enabled: true,
+      baseUrl: "http://speaches:8000/v1",
+      model: "Systran/faster-whisper-large-v3-turbo",
+      language: "en",
+      ...overrides,
+    },
+    tts: {
+      default: { enabled: false, url: "", voice: "", format: "" },
+      premium: { enabled: false, url: "" },
+      fallback: { enabled: false, url: "" },
+    },
+    limits: {
+      maxUploadSize: 25_000_000,
+      maxDurationSeconds: 600,
+      maxTextLength: 4096,
+    },
+  };
+}
+
+function createMockVerboseResponse(overrides?: Record<string, unknown>): Record<string, unknown> {
+  return {
+    text: "Hello, world!",
+    language: "en",
+    duration: 3.5,
+    segments: [
+      {
+        id: 0,
+        text: "Hello, world!",
+        start: 0.0,
+        end: 3.5,
+        avg_logprob: -0.25,
+        compression_ratio: 1.2,
+        no_speech_prob: 0.01,
+        seek: 0,
+        temperature: 0.0,
+        tokens: [1, 2, 3],
+      },
+    ],
+    ...overrides,
+  };
+}
+
+describe("SpeachesSttProvider", () => {
+  let provider: SpeachesSttProvider;
+  let config: SpeechConfig;
+
+  beforeEach(() => {
+    vi.clearAllMocks();
+    mockOpenAIConstructorCalls.length = 0;
+    config = createTestConfig();
+    provider = new SpeachesSttProvider(config);
+  });
+
+  // ==========================================
+  // Provider identity
+  // ==========================================
+  describe("name", () => {
+    it("should have the name 'speaches'", () => {
+      expect(provider.name).toBe("speaches");
+    });
+  });
+
+  // ==========================================
+  // transcribe
+  // ==========================================
+  describe("transcribe", () => {
+    it("should call OpenAI audio.transcriptions.create with correct parameters", async () => {
+      const mockResponse = createMockVerboseResponse();
+      mockCreate.mockResolvedValueOnce(mockResponse);
+
+      const audio = Buffer.from("fake-audio-data");
+      await provider.transcribe(audio);
+
+      expect(mockCreate).toHaveBeenCalledOnce();
+      const callArgs = mockCreate.mock.calls[0][0];
+      expect(callArgs.model).toBe("Systran/faster-whisper-large-v3-turbo");
+      expect(callArgs.language).toBe("en");
+      expect(callArgs.response_format).toBe("verbose_json");
+    });
+
+    it("should convert Buffer to File using toFile", async () => {
+      const mockResponse = createMockVerboseResponse();
+      mockCreate.mockResolvedValueOnce(mockResponse);
+
+      const audio = Buffer.from("fake-audio-data");
+      await provider.transcribe(audio);
+
+      expect(mockToFile).toHaveBeenCalledWith(audio, "audio.wav", {
+        type: "audio/wav",
+      });
+    });
+
+    it("should return TranscriptionResult with text and language", async () => {
+      const mockResponse = createMockVerboseResponse();
+      mockCreate.mockResolvedValueOnce(mockResponse);
+
+      const audio = Buffer.from("fake-audio-data");
+      const result = await provider.transcribe(audio);
+
+      expect(result.text).toBe("Hello, world!");
+      expect(result.language).toBe("en");
+    });
+
+    it("should return durationSeconds from verbose response", async () => {
+      const mockResponse = createMockVerboseResponse({ duration: 5.25 });
+      mockCreate.mockResolvedValueOnce(mockResponse);
+
+      const audio = Buffer.from("fake-audio-data");
+      const result = await provider.transcribe(audio);
+
+      expect(result.durationSeconds).toBe(5.25);
+    });
+
+    it("should map segments from verbose response", async () => {
+      const mockResponse = createMockVerboseResponse({
+        segments: [
+          {
+            id: 0,
+            text: "Hello,",
+            start: 0.0,
+            end: 1.5,
+            avg_logprob: -0.2,
+            compression_ratio: 1.1,
+            no_speech_prob: 0.01,
+            seek: 0,
+            temperature: 0.0,
+            tokens: [1, 2],
+          },
+          {
+            id: 1,
+            text: " world!",
+            start: 1.5,
+            end: 3.5,
+            avg_logprob: -0.3,
+            compression_ratio: 1.3,
+            no_speech_prob: 0.02,
+            seek: 0,
+            temperature: 0.0,
+            tokens: [3, 4],
+          },
+        ],
+      });
+      mockCreate.mockResolvedValueOnce(mockResponse);
+
+      const audio = Buffer.from("fake-audio-data");
+      const result = await provider.transcribe(audio);
+
+      expect(result.segments).toHaveLength(2);
+      expect(result.segments?.[0]).toEqual({
+        text: "Hello,",
+        start: 0.0,
+        end: 1.5,
+      });
+      expect(result.segments?.[1]).toEqual({
+        text: " world!",
+        start: 1.5,
+        end: 3.5,
+      });
+    });
+
+    it("should handle response without segments gracefully", async () => {
+      const mockResponse = createMockVerboseResponse({ segments: undefined });
+      mockCreate.mockResolvedValueOnce(mockResponse);
+
+      const audio = Buffer.from("fake-audio-data");
+      const result = await provider.transcribe(audio);
+
+      expect(result.text).toBe("Hello, world!");
+      expect(result.segments).toBeUndefined();
+    });
+
+    it("should handle response without duration gracefully", async () => {
+      const mockResponse = createMockVerboseResponse({ duration: undefined });
+      mockCreate.mockResolvedValueOnce(mockResponse);
+
+      const audio = Buffer.from("fake-audio-data");
+      const result = await provider.transcribe(audio);
+
+      expect(result.text).toBe("Hello, world!");
+      expect(result.durationSeconds).toBeUndefined();
+    });
+
+    // ------------------------------------------
+    // Options override
+    // ------------------------------------------
+    describe("options override", () => {
+      it("should use custom model from options when provided", async () => {
+        const mockResponse = createMockVerboseResponse();
+        mockCreate.mockResolvedValueOnce(mockResponse);
+
+        const audio = Buffer.from("fake-audio-data");
+        const options: TranscribeOptions = { model: "custom-whisper-model" };
+        await provider.transcribe(audio, options);
+
+        const callArgs = mockCreate.mock.calls[0][0];
+        expect(callArgs.model).toBe("custom-whisper-model");
+      });
+
+      it("should use custom language from options when provided", async () => {
+        const mockResponse = createMockVerboseResponse({ language: "fr" });
+        mockCreate.mockResolvedValueOnce(mockResponse);
+
+        const audio = Buffer.from("fake-audio-data");
+        const options: TranscribeOptions = { language: "fr" };
+        await provider.transcribe(audio, options);
+
+        const callArgs = mockCreate.mock.calls[0][0];
+        expect(callArgs.language).toBe("fr");
+      });
+
+      it("should pass through prompt option", async () => {
+        const mockResponse = createMockVerboseResponse();
+        mockCreate.mockResolvedValueOnce(mockResponse);
+
+        const audio = Buffer.from("fake-audio-data");
+        const options: TranscribeOptions = { prompt: "This is a meeting about project planning." };
+        await provider.transcribe(audio, options);
+
+        const callArgs = mockCreate.mock.calls[0][0];
+        expect(callArgs.prompt).toBe("This is a meeting about project planning.");
+      });
+
+      it("should pass through temperature option", async () => {
+        const mockResponse = createMockVerboseResponse();
+        mockCreate.mockResolvedValueOnce(mockResponse);
+
+        const audio = Buffer.from("fake-audio-data");
+        const options: TranscribeOptions = { temperature: 0.3 };
+        await provider.transcribe(audio, options);
+
+        const callArgs = mockCreate.mock.calls[0][0];
+        expect(callArgs.temperature).toBe(0.3);
+      });
+
+      it("should use custom mimeType for file conversion when provided", async () => {
+        const mockResponse = createMockVerboseResponse();
+        mockCreate.mockResolvedValueOnce(mockResponse);
+
+        const audio = Buffer.from("fake-audio-data");
+        const options: TranscribeOptions = { mimeType: "audio/mp3" };
+        await provider.transcribe(audio, options);
+
+        expect(mockToFile).toHaveBeenCalledWith(audio, "audio.mp3", {
+          type: "audio/mp3",
+        });
+      });
+    });
+
+    // ------------------------------------------
+    // Simple response fallback
+    // ------------------------------------------
+    describe("simple response fallback", () => {
+      it("should handle simple Transcription response (text only, no verbose fields)", async () => {
+        // Some configurations may return just { text: "..." } without verbose fields
+        const simpleResponse = { text: "Simple transcription result." };
+        mockCreate.mockResolvedValueOnce(simpleResponse);
+
+        const audio = Buffer.from("fake-audio-data");
+        const result = await provider.transcribe(audio);
+
+        expect(result.text).toBe("Simple transcription result.");
+        expect(result.language).toBe("en"); // Falls back to config language
+        expect(result.durationSeconds).toBeUndefined();
+        expect(result.segments).toBeUndefined();
+      });
+    });
+  });
+
+  // ==========================================
+  // Error handling
+  // ==========================================
+  describe("error handling", () => {
+    it("should throw a descriptive error on connection refused", async () => {
+      const connectionError = new Error("connect ECONNREFUSED 127.0.0.1:8000");
+      mockCreate.mockRejectedValueOnce(connectionError);
+
+      const audio = Buffer.from("fake-audio-data");
+      await expect(provider.transcribe(audio)).rejects.toThrow(
+        "STT transcription failed: connect ECONNREFUSED 127.0.0.1:8000"
+      );
+    });
+
+    it("should throw a descriptive error on timeout", async () => {
+      const timeoutError = new Error("Request timed out");
+      mockCreate.mockRejectedValueOnce(timeoutError);
+
+      const audio = Buffer.from("fake-audio-data");
+      await expect(provider.transcribe(audio)).rejects.toThrow(
+        "STT transcription failed: Request timed out"
+      );
+    });
+
+    it("should throw a descriptive error on API error", async () => {
+      const apiError = new Error("Invalid model: nonexistent-model");
+      mockCreate.mockRejectedValueOnce(apiError);
+
+      const audio = Buffer.from("fake-audio-data");
+      await expect(provider.transcribe(audio)).rejects.toThrow(
+        "STT transcription failed: Invalid model: nonexistent-model"
+      );
+    });
+
+    it("should handle non-Error thrown values", async () => {
+      mockCreate.mockRejectedValueOnce("unexpected string error");
+
+      const audio = Buffer.from("fake-audio-data");
+      await expect(provider.transcribe(audio)).rejects.toThrow(
+        "STT transcription failed: unexpected string error"
+      );
+    });
+  });
+
+  // ==========================================
+  // isHealthy
+  // ==========================================
+  describe("isHealthy", () => {
+    it("should return true when the server is reachable", async () => {
+      mockModelsList.mockResolvedValueOnce({ data: [{ id: "whisper-1" }] });
+
+      const healthy = await provider.isHealthy();
+      expect(healthy).toBe(true);
+    });
+
+    it("should return false when the server is unreachable", async () => {
+      mockModelsList.mockRejectedValueOnce(new Error("connect ECONNREFUSED"));
+
+      const healthy = await provider.isHealthy();
+      expect(healthy).toBe(false);
+    });
+
+    it("should not throw on health check failure", async () => {
+      mockModelsList.mockRejectedValueOnce(new Error("Network error"));
+
+      await expect(provider.isHealthy()).resolves.toBe(false);
+    });
+
+    it("should return false on unexpected error types", async () => {
+      mockModelsList.mockRejectedValueOnce("string error");
+
+      const healthy = await provider.isHealthy();
+      expect(healthy).toBe(false);
+    });
+  });
+
+  // ==========================================
+  // Config injection
+  // ==========================================
+  describe("config injection", () => {
+    it("should create OpenAI client with baseURL from config", () => {
+      // The constructor was called in beforeEach
+      expect(mockOpenAIConstructorCalls).toHaveLength(1);
+      expect(mockOpenAIConstructorCalls[0]).toEqual(
+        expect.objectContaining({
+          baseURL: "http://speaches:8000/v1",
+        })
+      );
+    });
+
+    it("should use custom baseURL from config", () => {
+      mockOpenAIConstructorCalls.length = 0;
+      const customConfig = createTestConfig({
+        baseUrl: "http://custom-speaches:9000/v1",
+      });
+      new SpeachesSttProvider(customConfig);
+
+      expect(mockOpenAIConstructorCalls).toHaveLength(1);
+      expect(mockOpenAIConstructorCalls[0]).toEqual(
+        expect.objectContaining({
+          baseURL: "http://custom-speaches:9000/v1",
+        })
+      );
+    });
+
+    it("should use default model from config for transcription", async () => {
+      const customConfig = createTestConfig({
+        model: "Systran/faster-whisper-small",
+      });
+      const customProvider = new SpeachesSttProvider(customConfig);
+
+      const mockResponse = createMockVerboseResponse();
+      mockCreate.mockResolvedValueOnce(mockResponse);
+
+      const audio = Buffer.from("fake-audio-data");
+      await customProvider.transcribe(audio);
+
+      const callArgs = mockCreate.mock.calls[0][0];
+      expect(callArgs.model).toBe("Systran/faster-whisper-small");
+    });
+
+    it("should use default language from config for transcription", async () => {
+      const customConfig = createTestConfig({ language: "de" });
+      const customProvider = new SpeachesSttProvider(customConfig);
+
+      const mockResponse = createMockVerboseResponse({ language: "de" });
+      mockCreate.mockResolvedValueOnce(mockResponse);
+
+      const audio = Buffer.from("fake-audio-data");
+      await customProvider.transcribe(audio);
+
+      const callArgs = mockCreate.mock.calls[0][0];
+      expect(callArgs.language).toBe("de");
+    });
+
+    it("should set a dummy API key for local Speaches server", () => {
+      expect(mockOpenAIConstructorCalls).toHaveLength(1);
+      expect(mockOpenAIConstructorCalls[0]).toEqual(
+        expect.objectContaining({
+          apiKey: "not-needed",
+        })
+      );
+    });
+  });
+});
--- a/apps/api/src/speech/providers/speaches-stt.provider.ts
+++ b/apps/api/src/speech/providers/speaches-stt.provider.ts
@@ -0,0 +1,180 @@
+/**
+ * SpeachesSttProvider
+ *
+ * Speech-to-text provider using Speaches (faster-whisper backend).
+ * Connects to the Speaches server via its OpenAI-compatible
+ * `/v1/audio/transcriptions` endpoint using the OpenAI SDK.
+ *
+ * Issue #390
+ */
+
+import { Injectable, Inject, Logger } from "@nestjs/common";
+import OpenAI from "openai";
+import { toFile } from "openai";
+import { speechConfig, type SpeechConfig } from "../speech.config";
+import type { ISTTProvider } from "../interfaces/stt-provider.interface";
+import type {
+  TranscribeOptions,
+  TranscriptionResult,
+  TranscriptionSegment,
+} from "../interfaces/speech-types";
+
+/**
+ * Derive file extension from a MIME type for use in the uploaded file name.
+ */
+function extensionFromMimeType(mimeType: string): string {
+  const mapping: Record<string, string> = {
+    "audio/wav": "wav",
+    "audio/wave": "wav",
+    "audio/x-wav": "wav",
+    "audio/mp3": "mp3",
+    "audio/mpeg": "mp3",
+    "audio/mp4": "mp4",
+    "audio/m4a": "m4a",
+    "audio/ogg": "ogg",
+    "audio/flac": "flac",
+    "audio/webm": "webm",
+    "audio/mpga": "mpga",
+  };
+  return mapping[mimeType] ?? "wav";
+}
+
+/**
+ * STT provider backed by a Speaches (faster-whisper) server.
+ *
+ * Speaches exposes an OpenAI-compatible `/v1/audio/transcriptions` endpoint,
+ * so we re-use the official OpenAI SDK with a custom `baseURL`.
+ *
+ * @example
+ * ```typescript
+ * const provider = new SpeachesSttProvider(speechConfig);
+ * const result = await provider.transcribe(audioBuffer, { language: "en" });
+ * console.log(result.text);
+ * ```
+ */
+@Injectable()
+export class SpeachesSttProvider implements ISTTProvider {
+  readonly name = "speaches";
+
+  private readonly logger = new Logger(SpeachesSttProvider.name);
+  private readonly client: OpenAI;
+  private readonly config: SpeechConfig;
+
+  constructor(
+    @Inject(speechConfig.KEY)
+    config: SpeechConfig
+  ) {
+    this.config = config;
+
+    this.client = new OpenAI({
+      baseURL: config.stt.baseUrl,
+      apiKey: "not-needed", // Speaches does not require an API key
+    });
+
+    this.logger.log(
+      `Speaches STT provider initialized (endpoint: ${config.stt.baseUrl}, model: ${config.stt.model})`
+    );
+  }
+
+  /**
+   * Transcribe audio data to text using the Speaches server.
+   *
+   * Sends the audio buffer to the `/v1/audio/transcriptions` endpoint
+   * with `response_format=verbose_json` to get segments and duration data.
+   *
+   * @param audio - Raw audio data as a Buffer
+   * @param options - Optional transcription parameters (model, language, prompt, temperature)
+   * @returns Transcription result with text, language, duration, and optional segments
+   * @throws {Error} If transcription fails (connection error, API error, etc.)
+   */
+  async transcribe(audio: Buffer, options?: TranscribeOptions): Promise<TranscriptionResult> {
+    const model = options?.model ?? this.config.stt.model;
+    const language = options?.language ?? this.config.stt.language;
+    const mimeType = options?.mimeType ?? "audio/wav";
+    const extension = extensionFromMimeType(mimeType);
+
+    try {
+      const file = await toFile(audio, `audio.${extension}`, {
+        type: mimeType,
+      });
+
+      const response = await this.client.audio.transcriptions.create({
+        file,
+        model,
+        language,
+        response_format: "verbose_json",
+        ...(options?.prompt !== undefined ? { prompt: options.prompt } : {}),
+        ...(options?.temperature !== undefined ? { temperature: options.temperature } : {}),
+      });
+
+      return this.mapResponse(response, language);
+    } catch (error: unknown) {
+      const message = error instanceof Error ? error.message : String(error);
+      this.logger.error(`Transcription failed: ${message}`);
+      throw new Error(`STT transcription failed: ${message}`);
+    }
+  }
+
+  /**
+   * Check if the Speaches server is healthy and reachable.
+   *
+   * Attempts to list models from the server. Returns true if the request
+   * succeeds, false otherwise.
+   *
+   * @returns true if the Speaches server is reachable and ready
+   */
+  async isHealthy(): Promise<boolean> {
+    try {
+      await this.client.models.list();
+      return true;
+    } catch (error: unknown) {
+      const message = error instanceof Error ? error.message : String(error);
+      this.logger.warn(`Speaches health check failed: ${message}`);
+      return false;
+    }
+  }
+
+  /**
+   * Map the OpenAI SDK transcription response to our TranscriptionResult type.
+   *
+   * Handles both verbose responses (with duration, segments) and simple
+   * responses (text only).
+   */
+  private mapResponse(
+    response: OpenAI.Audio.Transcriptions.TranscriptionVerbose | Record<string, unknown>,
+    fallbackLanguage: string
+  ): TranscriptionResult {
+    const text = (response as { text: string }).text;
+    const verboseResponse = response as {
+      text: string;
+      language?: string;
+      duration?: number;
+      segments?: {
+        text: string;
+        start: number;
+        end: number;
+      }[];
+    };
+
+    const result: TranscriptionResult = {
+      text,
+      language: verboseResponse.language ?? fallbackLanguage,
+    };
+
+    if (verboseResponse.duration !== undefined) {
+      result.durationSeconds = verboseResponse.duration;
+    }
+
+    if (verboseResponse.segments !== undefined && Array.isArray(verboseResponse.segments)) {
+      result.segments = verboseResponse.segments.map(
+        (segment): TranscriptionSegment => ({
+          text: segment.text,
+          start: segment.start,
+          end: segment.end,
+        })
+      );
+    }
+
+    return result;
+  }
+}
--- a/apps/api/src/speech/speech.module.ts
+++ b/apps/api/src/speech/speech.module.ts
@@ -4,36 +4,60 @@
 * NestJS module for speech-to-text (STT) and text-to-speech (TTS) services.
 * Provides a provider abstraction layer with graceful fallback for TTS tiers.
 *
+ * TTS providers are created dynamically based on configuration:
+ * - default: Kokoro-FastAPI (CPU, always available)
+ * - premium: Chatterbox (GPU, voice cloning)
+ * - fallback: Piper via OpenedAI Speech (ultra-lightweight CPU)
+ *
 * Imports:
 * - ConfigModule.forFeature(speechConfig) for speech configuration
 *
 * Providers:
 * - SpeechService: High-level speech operations with provider selection
- * - TTS_PROVIDERS: Empty Map<SpeechTier, ITTSProvider> (populated by provider modules)
+ * - TTS_PROVIDERS: Map<SpeechTier, ITTSProvider> populated by factory based on config
 *
 * Exports:
 * - SpeechService for use by other modules (e.g., controllers, brain)
 *
- * Issue #389
+ * Issue #389, #390, #391
 */

 import { Module, type OnModuleInit, Logger } from "@nestjs/common";
-import { ConfigModule } from "@nestjs/config";
-import { speechConfig, validateSpeechConfig } from "./speech.config";
+import { ConfigModule, ConfigService } from "@nestjs/config";
+import {
+  speechConfig,
+  validateSpeechConfig,
+  isSttEnabled,
+  type SpeechConfig,
+} from "./speech.config";
 import { SpeechService } from "./speech.service";
-import { TTS_PROVIDERS } from "./speech.constants";
-import type { SpeechTier } from "./interfaces/speech-types";
-import type { ITTSProvider } from "./interfaces/tts-provider.interface";
+import { STT_PROVIDER, TTS_PROVIDERS } from "./speech.constants";
+import { SpeachesSttProvider } from "./providers/speaches-stt.provider";
+import { createTTSProviders } from "./providers/tts-provider.factory";

@Module({
  imports: [ConfigModule.forFeature(speechConfig)],
  providers: [
    SpeechService,
-    // Default empty TTS providers map. Provider modules (Kokoro, Chatterbox, etc.)
-    // will register their providers in subsequent tasks.
+    // STT provider: conditionally register SpeachesSttProvider when STT is enabled
+    ...(isSttEnabled()
+      ? [
+          {
+            provide: STT_PROVIDER,
+            useClass: SpeachesSttProvider,
+          },
+        ]
+      : []),
    {
      provide: TTS_PROVIDERS,
-      useFactory: (): Map<SpeechTier, ITTSProvider> => new Map(),
+      useFactory: (configService: ConfigService) => {
+        const config = configService.get<SpeechConfig>("speech");
+        if (!config) {
+          return new Map();
+        }
+        return createTTSProviders(config);
+      },
+      inject: [ConfigService],
    },
  ],
  exports: [SpeechService],