feat: add support for Replicate TTS provider and models

- Updated environment variables documentation to include Replicate as a TTS provider option.
- Added Replicate to the sidebar for TTS provider guides.
- Included Replicate as a dependency in package.json and pnpm-lock.yaml.
- Enhanced audiobook chapter generation to normalize native speed settings based on the TTS provider.
- Improved error handling in TTS API routes to provide retry information for rate-limited responses.
- Updated AudiobookExportModal to reflect native speed support for Replicate models.
- Modified SettingsModal to set default model for Replicate.
- Enhanced SpeedControl component to conditionally render native speed controls based on provider support.
- Updated TTSContext to utilize effective native speed for TTS requests.
- Implemented Replicate request handling in the TTS generation logic.
- Added new documentation for configuring Replicate as a TTS provider.

README.md

@@ -18,7 +18,7 @@ OpenReader is an open source, self-host-friendly text-to-speech document reader
 
 ## ✨ Highlights
 
-- 🎯 **Multi-provider TTS** with OpenAI-compatible endpoints (OpenAI, DeepInfra, Kokoro, KittenTTS-FastAPI, Orpheus, custom).
+- 🎯 **Multi-provider TTS** with OpenAI-compatible endpoints and cloud providers (OpenAI, Replicate, DeepInfra, Kokoro, KittenTTS-FastAPI, Orpheus, custom).
 - 📖 **Read-along playback** for PDF/EPUB with sentence-aware narration.
 - ⏱️ **Word-by-word highlighting** via optional `whisper.cpp` timestamps.
 - 🛜 **Sync + library import** to bring docs across devices and from server-mounted folders.

docs-site/docs/configure/tts-provider-guides/replicate.md

@@ -0,0 +1,39 @@
+---
+title: Replicate
+---
+
+Use Replicate's hosted TTS models as your provider.
+
+## Setup
+
+**Environment variables (recommended for deployment):**
+
+```env
+API_KEY=r8_...
+NEXT_PUBLIC_DEFAULT_TTS_PROVIDER=replicate
+NEXT_PUBLIC_DEFAULT_TTS_MODEL=google/gemini-3.1-flash-tts
+```
+
+**Or in-app via Settings -> TTS Provider:**
+
+1. Set provider to `Replicate`.
+2. Enter your `API_KEY`.
+3. Choose a model and voice.
+
+Settings modal values override env vars. See [TTS Providers](../tts-providers) for how the two layers interact.
+
+## Notes
+
+- Built-in Replicate models:
+  - `google/gemini-3.1-flash-tts`
+  - `minimax/speech-2.8-turbo`
+  - `qwen/qwen3-tts`
+  - `inworld/tts-1.5-mini`
+- Native model speed is not available on all Replicate models; OpenReader hides/disables native speed controls where unsupported.
+- TTS requests are sent from the server, not the browser. The API key is never exposed to clients.
+
+## References
+
+- [Replicate](https://replicate.com/explore)
+- [TTS Providers](../tts-providers)
+- [TTS Environment Variables](../../reference/environment-variables#tts-provider-and-request-behavior)

docs-site/docs/configure/tts-providers.md

@@ -15,10 +15,17 @@ Set env vars as deployment-level defaults. Users (or you, in a single-user setup
 ## Providers
 
 - **OpenAI**: Cloud. Base URL pre-filled (`https://api.openai.com/v1`). API key required.
+- **Replicate**: Cloud. Base URL managed internally by OpenReader. API key required.
 - **Deepinfra**: Cloud. Base URL pre-filled (`https://api.deepinfra.com/v1/openai`). API key required.
 - **Custom OpenAI-Like**: Self-hosted or any custom endpoint. `API_BASE` must be set manually (typically ending in `/v1`). API key optional.
 
-For `OpenAI` and `Deepinfra` you only need to supply an API key. For `Custom OpenAI-Like` you must also set `API_BASE`.
+For `OpenAI`, `Deepinfra`, and `Replicate` you only need to supply an API key. For `Custom OpenAI-Like` you must also set `API_BASE`.
+
+## Built-in model catalogs
+
+- **Replicate** models: `google/gemini-3.1-flash-tts`, `minimax/speech-2.8-turbo`, `qwen/qwen3-tts`, `inworld/tts-1.5-mini`
+- **OpenAI** models: `tts-1`, `tts-1-hd`, `gpt-4o-mini-tts`
+- **Deepinfra** models: includes `hexgrad/Kokoro-82M` and additional hosted models (depending on API key / feature flags)
 
 ## Custom provider requirements
 
@@ -36,6 +43,7 @@ TTS requests originate from the **Next.js server**, not the browser. `API_BASE`
 - [Kokoro-FastAPI](./tts-provider-guides/kokoro-fastapi)
 - [KittenTTS-FastAPI](./tts-provider-guides/kitten-tts-fastapi)
 - [Orpheus-FastAPI](./tts-provider-guides/orpheus-fastapi)
+- [Replicate](./tts-provider-guides/replicate)
 - [DeepInfra](./tts-provider-guides/deepinfra)
 - [OpenAI](./tts-provider-guides/openai)
 - [Other](./tts-provider-guides/other)

docs-site/docs/deploy/vercel-deployment.md

@@ -49,8 +49,8 @@ We recommend setting these defaults for a production-like environment:
 - `NEXT_PUBLIC_ENABLE_DOCX_CONVERSION=false`: Disables DOCX upload (requires external tools anyway)
 - `NEXT_PUBLIC_ENABLE_DESTRUCTIVE_DELETE_ACTIONS=false`: Hides destructive "Delete All" actions
 - `NEXT_PUBLIC_ENABLE_TTS_PROVIDERS_TAB=false`: Hides the Settings -> TTS Provider section
-- `NEXT_PUBLIC_DEFAULT_TTS_PROVIDER=deepinfra`: Points default TTS to a scalable provider
+- `NEXT_PUBLIC_DEFAULT_TTS_PROVIDER=replicate`: Points default TTS to a scalable provider
-- `NEXT_PUBLIC_DEFAULT_TTS_MODEL=hexgrad/Kokoro-82M`: Uses a high-quality default model
+- `NEXT_PUBLIC_DEFAULT_TTS_MODEL=google/gemini-3.1-flash-tts`: Uses a high-quality default model
 - `NEXT_PUBLIC_SHOW_ALL_DEEPINFRA_MODELS=false`: Restricts usage to free models if no key is provided
 - `NEXT_PUBLIC_ENABLE_AUDIOBOOK_EXPORT=true`: (Optional) Controls audiobook export UI
 - `NEXT_PUBLIC_ENABLE_WORD_HIGHLIGHT=false`: (Optional) Controls word highlighting UI (requires timestamp backend)

docs-site/docs/docker-quick-start.md

@@ -8,7 +8,7 @@ import TabItem from '@theme/TabItem';
 ## Prerequisites
 
 - A recent Docker version installed
-- A TTS API server that OpenReader can reach (Kokoro-FastAPI, KittenTTS-FastAPI, Orpheus-FastAPI, DeepInfra, OpenAI, or equivalent)
+- A TTS API server that OpenReader can reach (Kokoro-FastAPI, KittenTTS-FastAPI, Orpheus-FastAPI, Replicate, DeepInfra, OpenAI, or equivalent)
 
 :::note
 If you have suitable hardware, you can run Kokoro locally with Docker. See [Kokoro-FastAPI](./configure/tts-provider-guides/kokoro-fastapi).

docs-site/docs/introduction.md

@@ -8,7 +8,7 @@ OpenReader is an open source text-to-speech document reader built with Next.js.
 
 > Previously named **OpenReader-WebUI**.
 
-It supports multiple TTS providers including OpenAI, DeepInfra, and custom OpenAI-compatible endpoints such as [Kokoro-FastAPI](https://github.com/remsky/Kokoro-FastAPI), [KittenTTS-FastAPI](https://github.com/richardr1126/KittenTTS-FastAPI), and [Orpheus-FastAPI](https://github.com/Lex-au/Orpheus-FastAPI).
+It supports multiple TTS providers including OpenAI, Replicate, DeepInfra, and custom OpenAI-compatible endpoints such as [Kokoro-FastAPI](https://github.com/remsky/Kokoro-FastAPI), [KittenTTS-FastAPI](https://github.com/richardr1126/KittenTTS-FastAPI), and [Orpheus-FastAPI](https://github.com/Lex-au/Orpheus-FastAPI).
 
 ## ✨ Highlights
 
@@ -18,6 +18,7 @@ It supports multiple TTS providers including OpenAI, DeepInfra, and custom OpenA
   - [**Orpheus-FastAPI**](https://github.com/Lex-au/Orpheus-FastAPI)
   - **Custom OpenAI-compatible**: any TTS API with `/v1/audio/voices` and `/v1/audio/speech` endpoints
   - **Cloud TTS providers**:
+    - [**Replicate**](https://replicate.com/explore): `google/gemini-3.1-flash-tts`, `minimax/speech-2.8-turbo`, `qwen/qwen3-tts`, and `inworld/tts-1.5-mini`
     - [**DeepInfra**](https://deepinfra.com/models/text-to-speech): Kokoro-82M and other hosted models
     - [**OpenAI API**](https://platform.openai.com/docs/pricing#transcription-and-speech): `tts-1`, `tts-1-hd`, and `gpt-4o-mini-tts`
 - 🛜 **Server-side Document Storage**

docs-site/docs/reference/environment-variables.md

@@ -379,7 +379,7 @@ Controls whether the **TTS Provider** section appears in the Settings modal.
  Sets the default TTS provider for new users.
  
  - Default: `custom-openai`
- - Example values: `deepinfra`, `openai`, `custom-openai`
+ - Example values: `replicate`, `deepinfra`, `openai`, `custom-openai`
  
  ### NEXT_PUBLIC_DEFAULT_TTS_MODEL
  

docs-site/sidebars.ts

@@ -23,6 +23,7 @@ const sidebars: SidebarsConfig = {
             'configure/tts-provider-guides/kokoro-fastapi',
             'configure/tts-provider-guides/kitten-tts-fastapi',
             'configure/tts-provider-guides/orpheus-fastapi',
+            'configure/tts-provider-guides/replicate',
             'configure/tts-provider-guides/deepinfra',
             'configure/tts-provider-guides/openai',
             'configure/tts-provider-guides/other',

package.json

@@ -59,6 +59,7 @@
     "react-pdf": "^9.2.1",
     "react-reader": "^2.0.15",
     "remark-gfm": "^4.0.1",
+    "replicate": "^1.4.0",
     "uuid": "^11.1.0"
   },
   "devDependencies": {

pnpm-lock.yaml

@@ -124,6 +124,9 @@ importers:
       remark-gfm:
         specifier: ^4.0.1
         version: 4.0.1
+      replicate:
+        specifier: ^1.4.0
+        version: 1.4.0
       uuid:
         specifier: ^11.1.0
         version: 11.1.0
@@ -3588,6 +3591,10 @@ packages:
   remark-stringify@11.0.0:
     resolution: {integrity: sha512-1OSmLd3awB/t8qdoEOMazZkNsfVTeY4fTsgzcQFdXNq8ToTN4ZGwrMnlda4K6smTFKD+GRV6O48i6Z4iKgPPpw==}
 
+  replicate@1.4.0:
+    resolution: {integrity: sha512-1ufKejfUVz/azy+5TnzQP7U1+MHVWZ6psnQ06az8byUUnRhT+DZ/MvewzB1NQYBVMgNKR7xPDtTwlcP5nv/5+w==}
+    engines: {git: '>=2.11.0', node: '>=18.0.0', npm: '>=7.19.0', yarn: '>=1.7.0'}
+
   resolve-from@4.0.0:
     resolution: {integrity: sha512-pb/MYmXstAkysRFx8piNI1tGFNQIFA3vkE3Gq4EuA1dF6gHp/+vgZqsCGJapvy8N3Q+4o7FwvquPJcnZ7RYy4g==}
     engines: {node: '>=4'}
@@ -8028,6 +8035,10 @@ snapshots:
       mdast-util-to-markdown: 2.1.2
       unified: 11.0.5
 
+  replicate@1.4.0:
+    optionalDependencies:
+      readable-stream: 4.7.0
+
   resolve-from@4.0.0: {}
 
   resolve-pkg-maps@1.0.0: {}

src/app/api/audiobook/chapter/route.ts

@@ -29,6 +29,7 @@ import { getOpenReaderTestNamespace, getUnclaimedUserIdForNamespace } from '@/li
 import { buildAllowedAudiobookUserIds, pickAudiobookOwner } from '@/lib/server/audiobooks/user-scope';
 import { getFFmpegPath } from '@/lib/server/audiobooks/ffmpeg-bin';
 import { generateTTSBuffer } from '@/lib/server/tts/generate';
+import { supportsNativeModelSpeed } from '@/lib/shared/tts-provider-catalog';
 import type { AudiobookGenerationSettings } from '@/types/client';
 import type { TTSAudiobookFormat } from '@/types/tts';
 
@@ -92,6 +93,12 @@ function s3NotConfiguredResponse(): NextResponse {
   );
 }
 
+function normalizeNativeSpeedForSettings(settings: AudiobookGenerationSettings): AudiobookGenerationSettings {
+  return supportsNativeModelSpeed(settings.ttsProvider, settings.ttsModel)
+    ? settings
+    : { ...settings, nativeSpeed: 1 };
+}
+
 function chapterFileMimeType(format: TTSAudiobookFormat): string {
   return format === 'mp3' ? 'audio/mpeg' : 'audio/mp4';
 }
@@ -300,18 +307,19 @@ export async function POST(request: NextRequest) {
       existingSettings = null;
     }
 
-    const incomingSettings = data.settings;
+    const incomingSettings = data.settings ? normalizeNativeSpeedForSettings(data.settings) : undefined;
     if (existingSettings && hasChapters && incomingSettings) {
+      const normalizedExistingSettings = normalizeNativeSpeedForSettings(existingSettings);
       const mismatch =
-        existingSettings.ttsProvider !== incomingSettings.ttsProvider ||
+        normalizedExistingSettings.ttsProvider !== incomingSettings.ttsProvider ||
-        existingSettings.ttsModel !== incomingSettings.ttsModel ||
+        normalizedExistingSettings.ttsModel !== incomingSettings.ttsModel ||
-        existingSettings.voice !== incomingSettings.voice ||
+        normalizedExistingSettings.voice !== incomingSettings.voice ||
-        existingSettings.nativeSpeed !== incomingSettings.nativeSpeed ||
+        normalizedExistingSettings.nativeSpeed !== incomingSettings.nativeSpeed ||
-        existingSettings.postSpeed !== incomingSettings.postSpeed ||
+        normalizedExistingSettings.postSpeed !== incomingSettings.postSpeed ||
-        existingSettings.format !== incomingSettings.format ||
+        normalizedExistingSettings.format !== incomingSettings.format ||
-        (existingSettings.ttsInstructions || '') !== (incomingSettings.ttsInstructions || '');
+        (normalizedExistingSettings.ttsInstructions || '') !== (incomingSettings.ttsInstructions || '');
       if (mismatch) {
-        return NextResponse.json({ error: 'Audiobook settings mismatch', settings: existingSettings }, { status: 409 });
+        return NextResponse.json({ error: 'Audiobook settings mismatch', settings: normalizedExistingSettings }, { status: 409 });
       }
     }
 

src/app/api/tts/route.ts

@@ -54,9 +54,22 @@ function getUpstreamStatus(error: unknown): number | undefined {
   const rec = error as Record<string, unknown>;
   if (typeof rec.status === 'number') return rec.status;
   if (typeof rec.statusCode === 'number') return rec.statusCode;
+  const response = rec.response as { status?: unknown } | undefined;
+  if (response && typeof response.status === 'number') return response.status;
   return undefined;
 }
 
+function getUpstreamRetryAfterSeconds(error: unknown): number | undefined {
+  if (typeof error !== 'object' || error === null) return undefined;
+  const rec = error as Record<string, unknown>;
+  const response = rec.response as { headers?: { get?: (name: string) => string | null } } | undefined;
+  const retryAfterHeader = response?.headers?.get?.('retry-after');
+  if (!retryAfterHeader) return undefined;
+  const parsed = Number(retryAfterHeader);
+  if (!Number.isFinite(parsed) || parsed <= 0) return undefined;
+  return Math.ceil(parsed);
+}
+
 export async function POST(req: NextRequest) {
   let providerForError: string | null = null;
   let didCreateDeviceIdCookie = false;
@@ -221,14 +234,18 @@ export async function POST(req: NextRequest) {
 
     const upstreamStatus = getUpstreamStatus(error);
     if (upstreamStatus === 429) {
+      const retryAfterSeconds = getUpstreamRetryAfterSeconds(error);
       const problem: ProblemDetails = {
         type: PROBLEM_TYPES.upstreamRateLimited,
         title: 'Upstream rate limited',
         status: 429,
-        detail: 'The TTS provider is rate limiting requests. Please try again shortly.',
+        detail: retryAfterSeconds
+          ? `The TTS provider is rate limiting requests. Please retry in about ${retryAfterSeconds}s.`
+          : 'The TTS provider is rate limiting requests. Please try again shortly.',
         code: 'UPSTREAM_RATE_LIMIT',
         provider: providerForError ?? undefined,
         upstreamStatus,
+        retryAfterSeconds,
         instance: req.nextUrl.pathname,
       };
 
@@ -236,11 +253,16 @@ export async function POST(req: NextRequest) {
         status: 429,
         headers: {
           'Content-Type': 'application/problem+json',
+          ...(retryAfterSeconds ? { 'Retry-After': String(retryAfterSeconds) } : {}),
         },
       });
     }
 
-    console.warn('Error generating TTS:', error);
+    const statusHint = getUpstreamStatus(error);
+    const errorMessage = error instanceof Error ? error.message : String(error);
+    console.warn(
+      `Error generating TTS${typeof statusHint === 'number' ? ` (upstream ${statusHint})` : ''}: ${errorMessage}`,
+    );
     const errorBody: TTSError = {
       code: 'TTS_GENERATION_FAILED',
       message: 'Failed to generate audio',

src/components/AudiobookExportModal.tsx

@@ -11,7 +11,7 @@ import { LoadingSpinner } from '@/components/Spinner';
 import { useConfig } from '@/contexts/ConfigContext';
 import { useTTS } from '@/contexts/TTSContext';
 import { VoicesControlBase } from '@/components/player/VoicesControlBase';
-import { supportsTtsInstructions } from '@/lib/shared/tts-provider-catalog';
+import { supportsNativeModelSpeed, supportsTtsInstructions } from '@/lib/shared/tts-provider-catalog';
 import type { TTSAudiobookChapter, TTSAudiobookFormat } from '@/types/tts';
 import { 
   getAudiobookStatus, 
@@ -73,6 +73,8 @@ export function AudiobookExportModal({
   const formatSpeed = useCallback((speed: number) => {
     return Number.isInteger(speed) ? speed.toString() : speed.toFixed(1);
   }, []);
+  const nativeSpeedSupported = useMemo(() => supportsNativeModelSpeed(ttsProvider, ttsModel), [ttsProvider, ttsModel]);
+  const effectiveNativeSpeed = nativeSpeedSupported ? nativeSpeed : 1;
 
   const hasExistingAudiobook = Boolean(bookId) || chapters.length > 0;
   const isLegacyAudiobookMissingSettings = hasExistingAudiobook && savedSettings === null;
@@ -113,12 +115,12 @@ export function AudiobookExportModal({
       ttsProvider,
       ttsModel,
       voice: nextVoice,
-      nativeSpeed,
+      nativeSpeed: effectiveNativeSpeed,
       postSpeed,
       format,
       ttsInstructions: supportsTtsInstructions(ttsModel) ? ttsInstructions : undefined,
     };
-  }, [savedSettings, audiobookVoice, configVoice, availableVoices, ttsProvider, ttsModel, ttsInstructions, nativeSpeed, postSpeed, format]);
+  }, [savedSettings, audiobookVoice, configVoice, availableVoices, ttsProvider, ttsModel, ttsInstructions, effectiveNativeSpeed, postSpeed, format]);
 
   const fetchExistingChapters = useCallback(async (soft: boolean = false) => {
     if (soft) {
@@ -529,11 +531,15 @@ export function AudiobookExportModal({
 			                                      <div className="text-sm font-medium text-foreground">{savedSettings.format.toUpperCase()}</div>
 			                                    </div>
 			                                  </div>
-			                                  <div className="grid grid-cols-2 gap-3">
+                                  <div className="grid grid-cols-2 gap-3">
-			                                    <div className="rounded-lg bg-base p-3">
+                                    <div className="rounded-lg bg-base p-3">
-			                                      <div className="text-[11px] uppercase tracking-wider text-muted mb-1">Native speed</div>
+                                      <div className="text-[11px] uppercase tracking-wider text-muted mb-1">Native speed</div>
-			                                      <div className="text-sm font-medium text-foreground">{formatSpeed(savedSettings.nativeSpeed)}x</div>
+                                      <div className="text-sm font-medium text-foreground">
-			                                    </div>
+                                        {supportsNativeModelSpeed(savedSettings.ttsProvider, savedSettings.ttsModel)
+                                          ? `${formatSpeed(savedSettings.nativeSpeed)}x`
+                                          : 'Not supported'}
+                                      </div>
+                                    </div>
 			                                    <div className="rounded-lg bg-base p-3">
 			                                      <div className="text-[11px] uppercase tracking-wider text-muted mb-1">Post speed</div>
 			                                      <div className="text-sm font-medium text-foreground">{formatSpeed(savedSettings.postSpeed)}x</div>
@@ -616,29 +622,39 @@ export function AudiobookExportModal({
 			                                    </div>
 			                                  </div>
 
-			                                  {/* Speed controls */}
+                                  {/* Speed controls */}
-			                                  <div className="rounded-lg bg-base p-3 space-y-3">
+                                  <div className="rounded-lg bg-base p-3 space-y-3">
-			                                    <div className="space-y-2">
+                                    {!nativeSpeedSupported && (
-			                                      <div className="flex items-center justify-between">
+                                      <div className="rounded-md border border-offbase bg-background px-2 py-1.5 text-[11px] text-muted">
-			                                        <label className="text-[11px] uppercase tracking-wider font-medium text-muted">Native model speed</label>
+                                        Native model speed is not available for this model.
-			                                        <span className="text-xs font-medium text-accent tabular-nums">{formatSpeed(nativeSpeed)}x</span>
+                                      </div>
-			                                      </div>
+                                    )}
-			                                      <input
-			                                        type="range"
-			                                        min="0.5"
-			                                        max="3"
-			                                        step="0.1"
-			                                        value={nativeSpeed}
-			                                        onChange={(e) => setNativeSpeed(parseFloat(e.target.value))}
-			                                        className="w-full h-1.5 bg-offbase rounded-full appearance-none cursor-pointer [&::-webkit-slider-runnable-track]:bg-offbase [&::-webkit-slider-runnable-track]:rounded-full [&::-webkit-slider-runnable-track]:h-1.5 [&::-webkit-slider-thumb]:appearance-none [&::-webkit-slider-thumb]:h-4 [&::-webkit-slider-thumb]:w-4 [&::-webkit-slider-thumb]:rounded-full [&::-webkit-slider-thumb]:bg-accent [&::-webkit-slider-thumb]:-mt-[5px] [&::-webkit-slider-thumb]:shadow-sm [&::-moz-range-track]:bg-offbase [&::-moz-range-track]:rounded-full [&::-moz-range-track]:h-1.5 [&::-moz-range-thumb]:appearance-none [&::-moz-range-thumb]:h-4 [&::-moz-range-thumb]:w-4 [&::-moz-range-thumb]:rounded-full [&::-moz-range-thumb]:bg-accent [&::-moz-range-thumb]:border-0"
-			                                      />
-			                                      <div className="flex justify-between text-[10px] text-muted">
-			                                        <span>0.5x</span>
-			                                        <span>3x</span>
-			                                      </div>
-			                                    </div>
 
-			                                    <div className="border-t border-offbase" />
+                                    {nativeSpeedSupported && (
+                                      <>
+                                        <div className="space-y-2">
+                                          <div className="flex items-center justify-between">
+                                            <label className="text-[11px] uppercase tracking-wider font-medium text-muted">Native model speed</label>
+                                            <span className="text-xs font-medium text-accent tabular-nums">{formatSpeed(nativeSpeed)}x</span>
+                                          </div>
+                                          <input
+                                            type="range"
+                                            min="0.5"
+                                            max="3"
+                                            step="0.1"
+                                            value={nativeSpeed}
+                                            onChange={(e) => setNativeSpeed(parseFloat(e.target.value))}
+                                            className="w-full h-1.5 bg-offbase rounded-full appearance-none cursor-pointer [&::-webkit-slider-runnable-track]:bg-offbase [&::-webkit-slider-runnable-track]:rounded-full [&::-webkit-slider-runnable-track]:h-1.5 [&::-webkit-slider-thumb]:appearance-none [&::-webkit-slider-thumb]:h-4 [&::-webkit-slider-thumb]:w-4 [&::-webkit-slider-thumb]:rounded-full [&::-webkit-slider-thumb]:bg-accent [&::-webkit-slider-thumb]:-mt-[5px] [&::-webkit-slider-thumb]:shadow-sm [&::-moz-range-track]:bg-offbase [&::-moz-range-track]:rounded-full [&::-moz-range-track]:h-1.5 [&::-moz-range-thumb]:appearance-none [&::-moz-range-thumb]:h-4 [&::-moz-range-thumb]:w-4 [&::-moz-range-thumb]:rounded-full [&::-moz-range-thumb]:bg-accent [&::-moz-range-thumb]:border-0"
+                                          />
+                                          <div className="flex justify-between text-[10px] text-muted">
+                                            <span>0.5x</span>
+                                            <span>3x</span>
+                                          </div>
+                                        </div>
+
+                                        <div className="border-t border-offbase" />
+                                      </>
+                                    )}
 
 			                                    <div className="space-y-2">
 			                                      <div className="flex items-center justify-between">

src/components/SettingsModal.tsx

@@ -491,7 +491,7 @@ export function SettingsModal({ className = '' }: { className?: string }) {
                     </nav>
 
                     {/* Content */}
-                    <div className="flex-1 p-4 overflow-y-auto">
+                    <div className="flex-1 min-w-0 p-4 overflow-y-auto">
                       {/* API Section */}
                       {activeSection === 'api' && (
                         <div className="space-y-4">
@@ -507,6 +507,9 @@ export function SettingsModal({ className = '' }: { className?: string }) {
                                 } else if (provider.id === 'custom-openai') {
                                   setModelValue('kokoro');
                                   setLocalBaseUrl('');
+                                } else if (provider.id === 'replicate') {
+                                  setModelValue('google/gemini-3.1-flash-tts');
+                                  setLocalBaseUrl('');
                                 } else if (provider.id === 'deepinfra') {
                                   setModelValue('hexgrad/Kokoro-82M');
                                   setLocalBaseUrl('https://api.deepinfra.com/v1/openai');
@@ -528,7 +531,10 @@ export function SettingsModal({ className = '' }: { className?: string }) {
                                 leaveFrom="opacity-100"
                                 leaveTo="opacity-0"
                               >
-                                <ListboxOptions className="absolute mt-1 w-full overflow-auto rounded-md bg-background py-1 shadow-lg ring-1 ring-offbase focus:outline-none z-50">
+                                <ListboxOptions
+                                  anchor="bottom start"
+                                  className="z-50 w-[var(--button-width)] max-h-60 overflow-y-auto overscroll-contain rounded-md bg-background py-1 shadow-lg ring-1 ring-offbase focus:outline-none [--anchor-gap:0.25rem]"
+                                >
                                   {ttsProviders.map((provider) => (
                                     <ListboxOption
                                       key={provider.id}
@@ -556,7 +562,7 @@ export function SettingsModal({ className = '' }: { className?: string }) {
                             </Listbox>
                           </div>
 
-                          {(localTTSProvider === 'custom-openai' || !localBaseUrl || localBaseUrl === '') && (
+                          {localTTSProvider !== 'replicate' && (localTTSProvider === 'custom-openai' || !localBaseUrl || localBaseUrl === '') && (
                             <div className="space-y-1.5">
                               <label className="block text-sm font-medium text-foreground">
                                 API Base URL
@@ -614,7 +620,10 @@ export function SettingsModal({ className = '' }: { className?: string }) {
                                   leaveFrom="opacity-100"
                                   leaveTo="opacity-0"
                                 >
-                                  <ListboxOptions className="absolute mt-1 w-full overflow-auto rounded-md bg-background py-1 shadow-lg ring-1 ring-offbase focus:outline-none z-50">
+                                  <ListboxOptions
+                                    anchor="bottom start"
+                                    className="z-50 w-[var(--button-width)] max-h-60 overflow-y-auto overscroll-contain rounded-md bg-background py-1 shadow-lg ring-1 ring-offbase focus:outline-none [--anchor-gap:0.25rem]"
+                                  >
                                     {ttsModels.map((model) => (
                                       <ListboxOption
                                         key={model.id}

src/components/player/SpeedControl.tsx

@@ -4,6 +4,7 @@ import { Input, Popover, PopoverButton, PopoverPanel } from '@headlessui/react';
 import { ChevronUpDownIcon, SpeedometerIcon } from '@/components/icons/Icons';
 import { useConfig } from '@/contexts/ConfigContext';
 import { useCallback, useEffect, useMemo, useState } from 'react';
+import { supportsNativeModelSpeed } from '@/lib/shared/tts-provider-catalog';
 
 export const SpeedControl = ({ 
   setSpeedAndRestart, 
@@ -12,7 +13,8 @@ export const SpeedControl = ({
   setSpeedAndRestart: (speed: number) => void;
   setAudioPlayerSpeedAndRestart: (speed: number) => void;
 }) => {
-  const { voiceSpeed, audioPlayerSpeed } = useConfig();
+  const { voiceSpeed, audioPlayerSpeed, ttsProvider, ttsModel } = useConfig();
+  const nativeSpeedSupported = supportsNativeModelSpeed(ttsProvider, ttsModel);
 
   const [localVoiceSpeed, setLocalVoiceSpeed] = useState(voiceSpeed);
   const [localAudioSpeed, setLocalAudioSpeed] = useState(audioPlayerSpeed);
@@ -53,28 +55,28 @@ export const SpeedControl = ({
   const triggerLabel = useMemo(
     () => {
       const parts: string[] = [];
-      if (localVoiceSpeed !== 1.0) parts.push(`${formatSpeed(localVoiceSpeed, 1)}x`);
+      if (nativeSpeedSupported && localVoiceSpeed !== 1.0) parts.push(`${formatSpeed(localVoiceSpeed, 1)}x`);
       if (localAudioSpeed !== 1.0) parts.push(`${formatSpeed(localAudioSpeed, 1)}x`);
       return parts.length > 0 ? parts.join(' • ') : '1x';
     },
-    [formatSpeed, localVoiceSpeed, localAudioSpeed]
+    [formatSpeed, localVoiceSpeed, localAudioSpeed, nativeSpeedSupported]
   );
 
   const compactTriggerLabel = useMemo(() => {
-    const voiceIsDefault = localVoiceSpeed === 1.0;
+    const voiceIsDefault = !nativeSpeedSupported || localVoiceSpeed === 1.0;
     const audioIsDefault = localAudioSpeed === 1.0;
 
     let combined = 1.0;
-    if (!voiceIsDefault && !audioIsDefault) {
+    if (nativeSpeedSupported && !voiceIsDefault && !audioIsDefault) {
       combined = (localVoiceSpeed + localAudioSpeed) / 2;
-    } else if (!voiceIsDefault) {
+    } else if (nativeSpeedSupported && !voiceIsDefault) {
       combined = localVoiceSpeed;
     } else if (!audioIsDefault) {
       combined = localAudioSpeed;
     }
 
     return `${formatSpeed(combined, 2)}x`;
-  }, [formatSpeed, localVoiceSpeed, localAudioSpeed]);
+  }, [formatSpeed, localVoiceSpeed, localAudioSpeed, nativeSpeedSupported]);
 
   const min = 0.5;
   const max = 3;
@@ -90,28 +92,36 @@ export const SpeedControl = ({
       </PopoverButton>
       <PopoverPanel anchor="top" className="absolute z-50 bg-base p-3 rounded-md shadow-lg border border-offbase">
         <div className="flex flex-col space-y-4">
-          <div className="flex flex-col space-y-2">
+          {!nativeSpeedSupported && (
-            <div className="text-xs font-medium text-foreground">Native model speed</div>
+            <div className="rounded-md border border-offbase bg-background px-2 py-1.5 text-[11px] text-muted">
-            <div className="flex justify-between">
+              Native model speed is not available for this model.
-              <span className="text-xs">{min.toFixed(1)}x</span>
-              <span className="text-xs font-bold">
-                {Number.isInteger(localVoiceSpeed) ? localVoiceSpeed.toString() : localVoiceSpeed.toFixed(1)}x
-              </span>
-              <span className="text-xs">{max.toFixed(1)}x</span>
             </div>
-            <Input
+          )}
-              type="range"
+
-              min={min}
+          {nativeSpeedSupported && (
-              max={max}
+            <div className="flex flex-col space-y-2">
-              step={step}
+              <div className="text-xs font-medium text-foreground">Native model speed</div>
-              value={localVoiceSpeed}
+              <div className="flex justify-between">
-              onChange={handleVoiceSpeedChange}
+                <span className="text-xs">{min.toFixed(1)}x</span>
-              onMouseUp={handleVoiceSpeedChangeComplete}
+                <span className="text-xs font-bold">
-              onKeyUp={handleVoiceSpeedChangeComplete}
+                  {Number.isInteger(localVoiceSpeed) ? localVoiceSpeed.toString() : localVoiceSpeed.toFixed(1)}x
-              onTouchEnd={handleVoiceSpeedChangeComplete}
+                </span>
-              className="w-full bg-offbase rounded-lg appearance-none cursor-pointer accent-accent [&::-webkit-slider-runnable-track]:bg-offbase [&::-webkit-slider-runnable-track]:rounded-lg [&::-webkit-slider-thumb]:appearance-none [&::-webkit-slider-thumb]:h-4 [&::-webkit-slider-thumb]:w-4 [&::-webkit-slider-thumb]:rounded-full [&::-webkit-slider-thumb]:bg-accent [&::-moz-range-track]:bg-offbase [&::-moz-range-track]:rounded-lg [&::-moz-range-thumb]:appearance-none [&::-moz-range-thumb]:h-4 [&::-moz-range-thumb]:w-4 [&::-moz-range-thumb]:rounded-full [&::-moz-range-thumb]:bg-accent"
+                <span className="text-xs">{max.toFixed(1)}x</span>
-            />
+              </div>
-          </div>
+              <Input
+                type="range"
+                min={min}
+                max={max}
+                step={step}
+                value={localVoiceSpeed}
+                onChange={handleVoiceSpeedChange}
+                onMouseUp={handleVoiceSpeedChangeComplete}
+                onKeyUp={handleVoiceSpeedChangeComplete}
+                onTouchEnd={handleVoiceSpeedChangeComplete}
+                className="w-full bg-offbase rounded-lg appearance-none cursor-pointer accent-accent [&::-webkit-slider-runnable-track]:bg-offbase [&::-webkit-slider-runnable-track]:rounded-lg [&::-webkit-slider-thumb]:appearance-none [&::-webkit-slider-thumb]:h-4 [&::-webkit-slider-thumb]:w-4 [&::-webkit-slider-thumb]:rounded-full [&::-webkit-slider-thumb]:bg-accent [&::-moz-range-track]:bg-offbase [&::-moz-range-track]:rounded-lg [&::-moz-range-thumb]:appearance-none [&::-moz-range-thumb]:h-4 [&::-moz-range-thumb]:w-4 [&::-moz-range-thumb]:rounded-full [&::-moz-range-thumb]:bg-accent"
+              />
+            </div>
+          )}
 
           <div className="flex flex-col space-y-2">
             <div className="text-xs font-medium text-foreground">Audio player speed</div>

src/contexts/TTSContext.tsx

@@ -39,7 +39,7 @@ import { getDocumentProgress, scheduleDocumentProgressSync } from '@/lib/client/
 import { withRetry, generateTTS, alignAudio } from '@/lib/client/api/audiobooks';
 import { preprocessSentenceForAudio, splitTextToTtsBlocks, splitTextToTtsBlocksEPUB } from '@/lib/shared/nlp';
 import { isKokoroModel } from '@/lib/shared/kokoro';
-import { supportsTtsInstructions } from '@/lib/shared/tts-provider-catalog';
+import { supportsNativeModelSpeed, supportsTtsInstructions } from '@/lib/shared/tts-provider-catalog';
 import { useAuthRateLimit } from '@/contexts/AuthRateLimitContext';
 import type {
   TTSLocation,
@@ -386,6 +386,10 @@ export function TTSProvider({ children }: { children: ReactNode }): ReactElement
   const [voice, setVoice] = useState(configVoice);
   const [ttsModel, setTTSModel] = useState(configTTSModel);
   const [ttsInstructions, setTTSInstructions] = useState(configTTSInstructions);
+  const effectiveNativeSpeed = useMemo(
+    () => (supportsNativeModelSpeed(configTTSProvider, ttsModel) ? speed : 1),
+    [configTTSProvider, ttsModel, speed],
+  );
 
   // Track pending preload requests
   const preloadRequests = useRef<Map<string, Promise<string>>>(new Map());
@@ -1015,7 +1019,7 @@ export function TTSProvider({ children }: { children: ReactNode }): ReactElement
       const alignmentKey = buildCacheKey(
         sentence,
         voice,
-        speed,
+        effectiveNativeSpeed,
         configTTSProvider,
         ttsModel,
       );
@@ -1053,7 +1057,7 @@ export function TTSProvider({ children }: { children: ReactNode }): ReactElement
     const audioCacheKey = buildCacheKey(
       sentence,
       voice,
-      speed,
+      effectiveNativeSpeed,
       configTTSProvider,
       ttsModel,
     );
@@ -1097,7 +1101,7 @@ export function TTSProvider({ children }: { children: ReactNode }): ReactElement
       const reqBody: TTSRequestPayload = {
         text: sentence,
         voice,
-        speed,
+        speed: effectiveNativeSpeed,
         format: 'mp3',
         model: ttsModel,
         instructions: supportsTtsInstructions(ttsModel) ? ttsInstructions : undefined,
@@ -1190,7 +1194,7 @@ export function TTSProvider({ children }: { children: ReactNode }): ReactElement
     }
   }, [
     voice,
-    speed,
+    effectiveNativeSpeed,
     ttsModel,
     ttsInstructions,
     audioCache,
@@ -1532,7 +1536,7 @@ export function TTSProvider({ children }: { children: ReactNode }): ReactElement
     const alignmentKey = buildCacheKey(
       sentence,
       voice,
-      speed,
+      effectiveNativeSpeed,
       configTTSProvider,
       ttsModel,
     );
@@ -1549,7 +1553,7 @@ export function TTSProvider({ children }: { children: ReactNode }): ReactElement
     if (howl) {
       howl.play();
     }
-  }, [sentences, currentIndex, playSentenceWithHowl, voice, speed, configTTSProvider, ttsModel]);
+  }, [sentences, currentIndex, playSentenceWithHowl, voice, effectiveNativeSpeed, configTTSProvider, ttsModel]);
 
   // Keep the current playback rate applied to the active Howl. Some browsers (notably
   // iOS Safari with HTML5 audio) can reset playbackRate after initial load/play.
@@ -1620,7 +1624,7 @@ export function TTSProvider({ children }: { children: ReactNode }): ReactElement
       const nextKey = buildCacheKey(
         nextSentence,
         voice,
-        speed,
+        effectiveNativeSpeed,
         configTTSProvider,
         ttsModel,
       );
@@ -1673,7 +1677,7 @@ export function TTSProvider({ children }: { children: ReactNode }): ReactElement
     } catch (error) {
       console.error('Error initiating preload:', error);
     }
-  }, [isAtLimit, currentIndex, sentences, audioCache, processSentence, voice, speed, configTTSProvider, ttsModel]);
+  }, [isAtLimit, currentIndex, sentences, audioCache, processSentence, voice, effectiveNativeSpeed, configTTSProvider, ttsModel]);
 
   /**
    * Main Playback Driver

src/lib/server/tts/generate.ts

@@ -1,7 +1,8 @@
 import OpenAI from 'openai';
+import Replicate from 'replicate';
 import { SpeechCreateParams } from 'openai/resources/audio/speech.mjs';
 import { isKokoroModel } from '@/lib/shared/kokoro';
-import { supportsTtsInstructions } from '@/lib/shared/tts-provider-catalog';
+import { supportsNativeModelSpeed, supportsTtsInstructions } from '@/lib/shared/tts-provider-catalog';
 import { LRUCache } from 'lru-cache';
 import { createHash } from 'crypto';
 import { access, readFile } from 'fs/promises';
@@ -45,6 +46,9 @@ type InflightEntry = {
   consumers: number;
 };
 
+let replicateQueue: Promise<void> = Promise.resolve();
+let replicateBlockedUntilMs = 0;
+
 const TTS_CACHE_MAX_SIZE_BYTES = Number(process.env.TTS_CACHE_MAX_SIZE_BYTES || 256 * 1024 * 1024); // 256MB
 const TTS_CACHE_TTL_MS = Number(process.env.TTS_CACHE_TTL_MS || 1000 * 60 * 30); // 30 minutes
 
@@ -63,17 +67,79 @@ function sleep(ms: number) {
   return new Promise((res) => setTimeout(res, ms));
 }
 
+function sleepWithSignal(ms: number, signal: AbortSignal): Promise<void> {
+  if (ms <= 0) return Promise.resolve();
+  if (signal.aborted) {
+    throw new DOMException('The operation was aborted.', 'AbortError');
+  }
+
+  return new Promise<void>((resolve, reject) => {
+    const timer = setTimeout(() => {
+      signal.removeEventListener('abort', onAbort);
+      resolve();
+    }, ms);
+
+    const onAbort = () => {
+      clearTimeout(timer);
+      signal.removeEventListener('abort', onAbort);
+      reject(new DOMException('The operation was aborted.', 'AbortError'));
+    };
+
+    signal.addEventListener('abort', onAbort, { once: true });
+  });
+}
+
 function getUpstreamStatus(error: unknown): number | undefined {
   if (typeof error !== 'object' || error === null) return undefined;
   const rec = error as Record<string, unknown>;
   if (typeof rec.status === 'number') return rec.status;
   if (typeof rec.statusCode === 'number') return rec.statusCode;
+  const response = rec.response as { status?: unknown } | undefined;
+  if (response && typeof response.status === 'number') return response.status;
   return undefined;
 }
 
+function getUpstreamRetryAfterSeconds(error: unknown): number | undefined {
+  if (typeof error !== 'object' || error === null) return undefined;
+  const rec = error as Record<string, unknown>;
+  const response = rec.response as { headers?: { get?: (name: string) => string | null } } | undefined;
+  const retryAfterHeader = response?.headers?.get?.('retry-after');
+  if (!retryAfterHeader) return undefined;
+  const parsed = Number(retryAfterHeader);
+  if (!Number.isFinite(parsed) || parsed <= 0) return undefined;
+  return parsed;
+}
+
+function applyReplicateCooldown(cooldownMs: number) {
+  if (!Number.isFinite(cooldownMs) || cooldownMs <= 0) return;
+  const next = Date.now() + cooldownMs;
+  replicateBlockedUntilMs = Math.max(replicateBlockedUntilMs, next);
+}
+
+async function runWithReplicateGate<T>(signal: AbortSignal, operation: () => Promise<T>): Promise<T> {
+  let release: (() => void) | undefined;
+  const prev = replicateQueue;
+  replicateQueue = new Promise<void>((resolve) => {
+    release = resolve;
+  });
+
+  await prev;
+  try {
+    const waitMs = Math.max(0, replicateBlockedUntilMs - Date.now());
+    if (waitMs > 0) {
+      await sleepWithSignal(waitMs, signal);
+    }
+    return await operation();
+  } finally {
+    release?.();
+  }
+}
+
 function resolveTTSRequest(input: ServerTTSRequest): ResolvedServerTTSRequest {
   const provider = input.provider || 'openai';
-  const rawModel = provider === 'deepinfra' && !input.model ? 'hexgrad/Kokoro-82M' : input.model;
+  const rawModel = provider === 'deepinfra' && !input.model ? 'hexgrad/Kokoro-82M'
+    : provider === 'replicate' && !input.model ? 'google/gemini-3.1-flash-tts'
+    : input.model;
   const model = (rawModel ?? 'gpt-4o-mini-tts') as SpeechCreateParams['model'];
 
   const normalizedVoice = (
@@ -83,7 +149,8 @@ function resolveTTSRequest(input: ServerTTSRequest): ResolvedServerTTSRequest {
   ) as string;
 
   const format = input.format || 'mp3';
-  const speed = Number.isFinite(Number(input.speed)) ? Number(input.speed) : 1;
+  const requestedSpeed = Number.isFinite(Number(input.speed)) ? Number(input.speed) : 1;
+  const speed = supportsNativeModelSpeed(provider, model as string) ? requestedSpeed : 1;
   const instructions = supportsTtsInstructions(model as string) && input.instructions
     ? input.instructions
     : undefined;
@@ -196,10 +263,112 @@ async function fetchTTSBufferWithRetry(
   }
 }
 
+function buildReplicateInput(request: ResolvedServerTTSRequest): Record<string, unknown> {
+  const model = request.model as string;
+
+  if (model === 'google/gemini-3.1-flash-tts') {
+    const input: Record<string, unknown> = {
+      text: request.text,
+      voice: request.voice,
+    };
+    if (request.instructions) {
+      input.prompt = request.instructions;
+    }
+    return input;
+  }
+
+  if (model === 'minimax/speech-2.8-turbo') {
+    const input: Record<string, unknown> = {
+      text: request.text,
+      voice_id: request.voice,
+      audio_format: request.format === 'mp3' ? 'mp3' : 'wav',
+    };
+    if (request.speed !== 1) {
+      input.speed = Math.max(0.5, Math.min(2.0, request.speed));
+    }
+    return input;
+  }
+
+  if (model === 'qwen/qwen3-tts') {
+    const input: Record<string, unknown> = {
+      text: request.text,
+      mode: 'custom_voice',
+      speaker: request.voice,
+    };
+    if (request.instructions) {
+      input.style_instruction = request.instructions;
+    }
+    return input;
+  }
+
+  if (model === 'inworld/tts-1.5-mini') {
+    const input: Record<string, unknown> = {
+      text: request.text,
+      voice_id: request.voice,
+      audio_format: request.format === 'mp3' ? 'mp3' : 'wav',
+    };
+    if (request.speed !== 1) {
+      input.speaking_rate = request.speed;
+    }
+    return input;
+  }
+
+  return { text: request.text };
+}
+
+async function runReplicateRequest(request: ResolvedServerTTSRequest, signal: AbortSignal): Promise<Buffer> {
+  const replicate = new Replicate({ auth: request.apiKey });
+  const input = buildReplicateInput(request);
+  const modelId = request.model as `${string}/${string}`;
+
+  return runWithReplicateGate(signal, async () => {
+    const maxRetries = Number(process.env.TTS_MAX_RETRIES ?? 2);
+    let attempt = 0;
+
+    for (; ;) {
+      try {
+        const output = await replicate.run(modelId, { input, signal }) as unknown;
+
+        // Output is a URI string pointing to the generated audio file
+        const audioUrl = typeof output === 'string' ? output : String(output);
+        const audioResponse = await fetch(audioUrl, { signal });
+        if (!audioResponse.ok) {
+          throw new Error(`Failed to fetch Replicate audio: ${audioResponse.status}`);
+        }
+        const buffer = await audioResponse.arrayBuffer();
+        return Buffer.from(buffer);
+      } catch (error) {
+        if (signal.aborted || (error instanceof Error && error.name === 'AbortError')) {
+          throw error;
+        }
+
+        const status = getUpstreamStatus(error) ?? 0;
+        const retryable = status === 429 || status >= 500;
+        const retryAfterSeconds = status === 429 ? getUpstreamRetryAfterSeconds(error) : undefined;
+        const delay = retryAfterSeconds ? Math.max(retryAfterSeconds * 1000, 1000) : 10_000;
+        if (status === 429) {
+          applyReplicateCooldown(delay);
+        }
+
+        if (!retryable || attempt >= maxRetries) {
+          throw error;
+        }
+
+        await sleepWithSignal(delay, signal);
+        attempt += 1;
+      }
+    }
+  });
+}
+
 async function runProviderRequest(request: ResolvedServerTTSRequest, signal: AbortSignal): Promise<Buffer> {
   const mockBuffer = await getTestMockTtsBuffer(request.testNamespace);
   if (mockBuffer) return mockBuffer;
 
+  if (request.provider === 'replicate') {
+    return runReplicateRequest(request, signal);
+  }
+
   const openai = new OpenAI({
     apiKey: request.apiKey,
     baseURL: request.baseUrl,

src/lib/shared/tts-provider-catalog.ts

@@ -1,6 +1,6 @@
 import { isKokoroModel } from '@/lib/shared/kokoro';
 
-export type TtsProviderId = 'custom-openai' | 'deepinfra' | 'openai';
+export type TtsProviderId = 'custom-openai' | 'replicate' | 'deepinfra' | 'openai';
 export type TtsVoiceSource = 'static' | 'deepinfra-api' | 'custom-openai-api';
 
 export interface TtsModelDefinition {
@@ -54,6 +54,13 @@ const DEEPINFRA_MODELS_LIMITED: TtsModelDefinition[] = [
   { id: 'hexgrad/Kokoro-82M', name: 'hexgrad/Kokoro-82M' },
 ];
 
+const REPLICATE_MODELS: TtsModelDefinition[] = [
+  { id: 'google/gemini-3.1-flash-tts', name: 'Gemini 3.1 Flash TTS' },
+  { id: 'minimax/speech-2.8-turbo', name: 'MiniMax Speech 2.8 Turbo' },
+  { id: 'qwen/qwen3-tts', name: 'Qwen3 TTS' },
+  { id: 'inworld/tts-1.5-mini', name: 'Inworld TTS 1.5 Mini' },
+];
+
 const DEFAULT_MODELS: TtsModelDefinition[] = [{ id: 'tts-1', name: 'TTS-1' }];
 
 export const OPENAI_DEFAULT_VOICES = ['alloy', 'echo', 'fable', 'onyx', 'nova', 'shimmer'] as const;
@@ -71,6 +78,22 @@ export const KOKORO_DEFAULT_VOICES = [
 export const ORPHEUS_DEFAULT_VOICES = ['tara', 'leah', 'jess', 'leo', 'dan', 'mia', 'zac'] as const;
 export const SESAME_DEFAULT_VOICES = ['conversational_a', 'conversational_b', 'read_speech_a', 'read_speech_b', 'read_speech_c', 'read_speech_d', 'none'] as const;
 
+// Replicate model voices
+export const GEMINI_FLASH_TTS_VOICES = [
+  'Zephyr', 'Puck', 'Charon', 'Kore', 'Fenrir', 'Leda', 'Orus', 'Aoede',
+  'Callirrhoe', 'Autonoe', 'Enceladus', 'Iapetus', 'Umbriel', 'Algenib',
+  'Despina', 'Erinome', 'Laomedeia', 'Achernar', 'Algieba', 'Schedar',
+  'Gacrux', 'Pulcherrima', 'Achird', 'Zubenelgenubi', 'Vindemiatrix',
+  'Sadachbia', 'Sadaltager', 'Sulafat', 'Alnilam', 'Rasalgethi',
+] as const;
+export const MINIMAX_SPEECH_VOICES = [
+  'Deep_Voice_Man', 'Imposing_Manner', 'Elegant_Man', 'Casual_Guy',
+  'Friendly_Person', 'Decent_Boy', 'Lively_Girl', 'Exuberant_Girl',
+  'Inspirational_girl', 'Young_Knight', 'Abbess', 'Wise_Woman',
+] as const;
+export const QWEN3_TTS_VOICES = ['Aiden', 'Dylan'] as const;
+export const INWORLD_TTS_VOICES = ['Ashley', 'Dennis', 'Alex', 'Darlene'] as const;
+
 export const TTS_PROVIDER_DEFINITIONS: TtsProviderDefinition[] = [
   {
     id: 'custom-openai',
@@ -78,6 +101,12 @@ export const TTS_PROVIDER_DEFINITIONS: TtsProviderDefinition[] = [
     supportsCustomModel: true,
     models: () => CUSTOM_OPENAI_MODELS,
   },
+  {
+    id: 'replicate',
+    name: 'Replicate',
+    supportsCustomModel: false,
+    models: () => REPLICATE_MODELS,
+  },
   {
     id: 'deepinfra',
     name: 'Deepinfra',
@@ -97,8 +126,31 @@ export const TTS_PROVIDER_DEFINITIONS: TtsProviderDefinition[] = [
   },
 ];
 
+const MODELS_WITH_INSTRUCTIONS = new Set([
+  'gpt-4o-mini-tts',
+  'google/gemini-3.1-flash-tts',
+  'qwen/qwen3-tts',
+]);
+
+const REPLICATE_MODELS_WITHOUT_NATIVE_SPEED = new Set([
+  'google/gemini-3.1-flash-tts',
+  'qwen/qwen3-tts',
+]);
+
 export function supportsTtsInstructions(model: string | null | undefined): boolean {
-  return model === 'gpt-4o-mini-tts';
+  return !!model && MODELS_WITH_INSTRUCTIONS.has(model);
+}
+
+export function supportsNativeModelSpeed(provider: string | null | undefined, model: string | null | undefined): boolean {
+  if (!model) {
+    return true;
+  }
+
+  if (provider === 'replicate' && REPLICATE_MODELS_WITHOUT_NATIVE_SPEED.has(model)) {
+    return false;
+  }
+
+  return true;
 }
 
 export function getProviderDefinition(provider: string | null | undefined): TtsProviderDefinition | undefined {
@@ -128,6 +180,22 @@ export function getDefaultVoices(provider: string, model: string): string[] {
     return [...CUSTOM_OPENAI_DEFAULT_VOICES];
   }
 
+  if (provider === 'replicate') {
+    if (model === 'google/gemini-3.1-flash-tts') {
+      return [...GEMINI_FLASH_TTS_VOICES];
+    }
+    if (model === 'minimax/speech-2.8-turbo') {
+      return [...MINIMAX_SPEECH_VOICES];
+    }
+    if (model === 'qwen/qwen3-tts') {
+      return [...QWEN3_TTS_VOICES];
+    }
+    if (model === 'inworld/tts-1.5-mini') {
+      return [...INWORLD_TTS_VOICES];
+    }
+    return [...GEMINI_FLASH_TTS_VOICES];
+  }
+
   if (provider === 'deepinfra') {
     if (model === 'hexgrad/Kokoro-82M') {
       return [...KOKORO_DEFAULT_VOICES];