diff --git a/compute/core/package.json b/compute/core/package.json
index fe9bb45..9141f07 100644
--- a/compute/core/package.json
+++ b/compute/core/package.json
@@ -12,6 +12,8 @@
     "pdfjs-dist": "4.8.69"
   },
   "exports": {
-    ".": "./src/index.ts"
+    ".": "./src/index.ts",
+    "./contracts": "./src/contracts.ts",
+    "./local-runtime": "./src/local-runtime.ts"
   }
 }
diff --git a/compute/core/src/contracts.ts b/compute/core/src/contracts.ts
new file mode 100644
index 0000000..04e1fb4
--- /dev/null
+++ b/compute/core/src/contracts.ts
@@ -0,0 +1,62 @@
+import type { TTSSentenceAlignment } from './types/tts';
+import type { ParsedPdfDocument } from './types/parsed-pdf';
+
+export type {
+  TTSAudioBuffer,
+  TTSAudioBytes,
+  TTSSentenceAlignment,
+  TTSSentenceWord,
+} from './types/tts';
+export type {
+  ParsedPdfBlockKind,
+  ParsedPdfBlockFragment,
+  ParsedPdfBlock,
+  ParsedPdfPage,
+  ParsedPdfDocument,
+} from './types/parsed-pdf';
+
+export const ALIGN_QUEUE_NAME = 'whisper-align';
+export const PDF_LAYOUT_QUEUE_NAME = 'pdf-layout';
+
+export interface WhisperAlignJobRequest {
+  text: string;
+  lang?: string;
+  cacheKey?: string;
+  audioObjectKey: string;
+}
+
+export interface WhisperAlignJobResult {
+  alignments: TTSSentenceAlignment[];
+  timing?: WorkerJobTiming;
+}
+
+export interface PdfLayoutJobRequest {
+  documentId: string;
+  namespace: string | null;
+  documentObjectKey: string;
+}
+
+export interface PdfLayoutJobResult {
+  parsed: ParsedPdfDocument;
+  timing?: WorkerJobTiming;
+}
+
+export type WorkerJobState = 'queued' | 'running' | 'succeeded' | 'failed';
+
+export interface WorkerJobErrorShape {
+  message: string;
+  code?: string;
+}
+
+export interface WorkerJobTiming {
+  queueWaitMs?: number;
+  s3FetchMs?: number;
+  computeMs?: number;
+}
+
+export interface WorkerJobStatusResponse<Result> {
+  status: WorkerJobState;
+  result?: Result;
+  error?: WorkerJobErrorShape;
+  timing?: WorkerJobTiming;
+}
diff --git a/compute/core/src/index.ts b/compute/core/src/index.ts
index 24afe87..54397e2 100644
--- a/compute/core/src/index.ts
+++ b/compute/core/src/index.ts
@@ -1,96 +1,6 @@
-import type { TTSSentenceAlignment } from './types/tts';
-import type { ParsedPdfDocument } from './types/parsed-pdf';
-import { ensureWhisperModel } from './whisper/ensureModel';
-import { alignAudioWithText } from './whisper/alignment';
-import { ensureModel as ensurePdfLayoutModel } from './pdf-layout/ensureModel';
-import { parsePdf } from './pdf-layout/parsePdf';
-
-export type {
-  TTSAudioBuffer,
-  TTSAudioBytes,
-  TTSSentenceAlignment,
-  TTSSentenceWord,
-} from './types/tts';
-export type {
-  ParsedPdfBlockKind,
-  ParsedPdfBlockFragment,
-  ParsedPdfBlock,
-  ParsedPdfPage,
-  ParsedPdfDocument,
-} from './types/parsed-pdf';
-
-export const ALIGN_QUEUE_NAME = 'whisper-align';
-export const PDF_LAYOUT_QUEUE_NAME = 'pdf-layout';
-
-export interface WhisperAlignJobRequest {
-  text: string;
-  lang?: string;
-  cacheKey?: string;
-  audioObjectKey: string;
-}
-
-export interface WhisperAlignJobResult {
-  alignments: TTSSentenceAlignment[];
-  timing?: WorkerJobTiming;
-}
-
-export interface PdfLayoutJobRequest {
-  documentId: string;
-  namespace: string | null;
-  documentObjectKey: string;
-}
-
-export interface PdfLayoutJobResult {
-  parsed: ParsedPdfDocument;
-  timing?: WorkerJobTiming;
-}
-
-export type WorkerJobState = 'queued' | 'running' | 'succeeded' | 'failed';
-
-export interface WorkerJobErrorShape {
-  message: string;
-  code?: string;
-}
-
-export interface WorkerJobTiming {
-  queueWaitMs?: number;
-  s3FetchMs?: number;
-  computeMs?: number;
-}
-
-export interface WorkerJobStatusResponse<Result> {
-  status: WorkerJobState;
-  result?: Result;
-  error?: WorkerJobErrorShape;
-  timing?: WorkerJobTiming;
-}
-
-export async function ensureComputeModels(): Promise<void> {
-  await Promise.all([ensureWhisperModel(), ensurePdfLayoutModel()]);
-}
-
-export async function runWhisperAlignmentFromAudioBuffer(input: {
-  audioBuffer: ArrayBuffer;
-  text: string;
-  cacheKey?: string;
-  lang?: string;
-}): Promise<WhisperAlignJobResult> {
-  const alignments = await alignAudioWithText(
-    input.audioBuffer,
-    input.text,
-    input.cacheKey,
-    { lang: input.lang },
-  );
-  return { alignments };
-}
-
-export async function runPdfLayoutFromPdfBuffer(input: {
-  documentId: string;
-  pdfBytes: ArrayBuffer;
-}): Promise<PdfLayoutJobResult> {
-  const parsed = await parsePdf({
-    documentId: input.documentId,
-    pdfBytes: input.pdfBytes,
-  });
-  return { parsed };
-}
+export * from './contracts';
+export {
+  ensureComputeModels,
+  runPdfLayoutFromPdfBuffer,
+  runWhisperAlignmentFromAudioBuffer,
+} from './local-runtime';
diff --git a/compute/core/src/local-runtime.ts b/compute/core/src/local-runtime.ts
new file mode 100644
index 0000000..5a794b8
--- /dev/null
+++ b/compute/core/src/local-runtime.ts
@@ -0,0 +1,34 @@
+import { ensureWhisperModel } from './whisper/ensureModel';
+import { alignAudioWithText } from './whisper/alignment';
+import { ensureModel as ensurePdfLayoutModel } from './pdf-layout/ensureModel';
+import { parsePdf } from './pdf-layout/parsePdf';
+
+export async function ensureComputeModels(): Promise<void> {
+  await Promise.all([ensureWhisperModel(), ensurePdfLayoutModel()]);
+}
+
+export async function runWhisperAlignmentFromAudioBuffer(input: {
+  audioBuffer: ArrayBuffer;
+  text: string;
+  cacheKey?: string;
+  lang?: string;
+}) {
+  const alignments = await alignAudioWithText(
+    input.audioBuffer,
+    input.text,
+    input.cacheKey,
+    { lang: input.lang },
+  );
+  return { alignments };
+}
+
+export async function runPdfLayoutFromPdfBuffer(input: {
+  documentId: string;
+  pdfBytes: ArrayBuffer;
+}) {
+  const parsed = await parsePdf({
+    documentId: input.documentId,
+    pdfBytes: input.pdfBytes,
+  });
+  return { parsed };
+}
diff --git a/compute/worker/Dockerfile b/compute/worker/Dockerfile
index 2e6d613..9872e70 100644
--- a/compute/worker/Dockerfile
+++ b/compute/worker/Dockerfile
@@ -26,4 +26,4 @@ ENV COMPUTE_WORKER_PORT=8081
 
 EXPOSE 8081
 
-CMD ["pnpm", "dev"]
+CMD ["node", "--import", "tsx", "src/server.ts"]
diff --git a/compute/worker/package.json b/compute/worker/package.json
index bd85999..4b3b1c7 100644
--- a/compute/worker/package.json
+++ b/compute/worker/package.json
@@ -16,9 +16,7 @@
     "fastify": "^5.6.2",
     "pino": "^10.3.1",
     "pino-pretty": "^13.1.2",
+    "tsx": "^4.22.3",
     "zod": "^4.1.12"
-  },
-  "devDependencies": {
-    "tsx": "^4.22.3"
   }
 }
diff --git a/compute/worker/src/server.ts b/compute/worker/src/server.ts
index 66551aa..4e62162 100644
--- a/compute/worker/src/server.ts
+++ b/compute/worker/src/server.ts
@@ -24,13 +24,15 @@ import {
   ensureComputeModels,
   runPdfLayoutFromPdfBuffer,
   runWhisperAlignmentFromAudioBuffer,
+} from '@openreader/compute-core/local-runtime';
+import {
   type PdfLayoutJobRequest,
   type PdfLayoutJobResult,
   type WhisperAlignJobRequest,
   type WhisperAlignJobResult,
   type WorkerJobStatusResponse,
   type WorkerJobTiming,
-} from '@openreader/compute-core';
+} from '@openreader/compute-core/contracts';
 import { GetObjectCommand, S3Client } from '@aws-sdk/client-s3';
 
 const JOBS_STREAM_NAME = 'compute_jobs';
diff --git a/next.config.ts b/next.config.ts
index 3340a9e..73e514e 100644
--- a/next.config.ts
+++ b/next.config.ts
@@ -1,4 +1,5 @@
 import type { NextConfig } from "next";
+import path from "node:path";
 
 const securityHeaders = [
   { key: 'X-Content-Type-Options', value: 'nosniff' },
@@ -43,7 +44,7 @@ const nextConfig: NextConfig = {
       canvas: '@napi-rs/canvas',
     },
   },
-  transpilePackages: ['@openreader/compute-core'],
+  transpilePackages: computeLocal ? ['@openreader/compute-core'] : [],
   serverExternalPackages,
   outputFileTracingIncludes: {
     '/api/audiobook': [
@@ -75,6 +76,36 @@ const nextConfig: NextConfig = {
         },
       }
     : {}),
+  webpack: (config, { isServer }) => {
+    if (isServer) {
+      // Use runtime require to avoid adding an explicit webpack TS dependency.
+      const { DefinePlugin } = require('webpack') as { DefinePlugin: new (defs: Record<string, string>) => unknown };
+      config.plugins = config.plugins || [];
+      config.plugins.push(
+        new DefinePlugin({
+          __OPENREADER_COMPUTE_MODE__: JSON.stringify(computeMode),
+        }),
+      );
+    }
+    if (isServer && !computeLocal) {
+      const workerComputeEntry = path.resolve(__dirname, 'src/lib/server/compute/index.worker.ts');
+      const computeIndexTs = path.resolve(__dirname, 'src/lib/server/compute/index.ts');
+      const computeIndexNoExt = path.resolve(__dirname, 'src/lib/server/compute/index');
+      const computeDir = path.resolve(__dirname, 'src/lib/server/compute');
+      config.resolve.alias = {
+        ...(config.resolve.alias || {}),
+        '@/lib/server/compute$': workerComputeEntry,
+        '@/lib/server/compute/index$': workerComputeEntry,
+        [`${computeIndexTs}$`]: workerComputeEntry,
+        [`${computeIndexNoExt}$`]: workerComputeEntry,
+        [`${computeDir}$`]: workerComputeEntry,
+        '@openreader/compute-core/local-runtime$': false,
+        'onnxruntime-node$': false,
+        '@huggingface/tokenizers$': false,
+      };
+    }
+    return config;
+  },
 };
 
 export default nextConfig;
diff --git a/pnpm-lock.yaml b/pnpm-lock.yaml
index 7303f48..fdbeb0b 100644
--- a/pnpm-lock.yaml
+++ b/pnpm-lock.yaml
@@ -233,13 +233,12 @@ importers:
       pino-pretty:
         specifier: ^13.1.2
         version: 13.1.3
-      zod:
-        specifier: ^4.1.12
-        version: 4.4.3
-    devDependencies:
       tsx:
         specifier: ^4.22.3
         version: 4.22.3
+      zod:
+        specifier: ^4.1.12
+        version: 4.4.3
 
 packages:
 
diff --git a/src/lib/server/compute/index.ts b/src/lib/server/compute/index.ts
index 5442429..c83d790 100644
--- a/src/lib/server/compute/index.ts
+++ b/src/lib/server/compute/index.ts
@@ -2,9 +2,16 @@ import type { ComputeBackend, ComputeMode } from '@/lib/server/compute/types';
 import { isComputeModeAvailable, readComputeMode } from '@/lib/server/compute/mode';
 import { WorkerComputeBackend } from '@/lib/server/compute/worker';
 
+declare const __OPENREADER_COMPUTE_MODE__: 'local' | 'worker' | 'none';
+
 let backendPromise: Promise<ComputeBackend> | null = null;
 
 async function createBackend(): Promise<ComputeBackend> {
+  if (__OPENREADER_COMPUTE_MODE__ === 'worker') return new WorkerComputeBackend();
+  if (__OPENREADER_COMPUTE_MODE__ === 'local') {
+    const { LocalComputeBackend } = await import('@/lib/server/compute/local');
+    return new LocalComputeBackend();
+  }
   const mode: ComputeMode = readComputeMode();
   if (mode === 'worker') return new WorkerComputeBackend();
   const { LocalComputeBackend } = await import('@/lib/server/compute/local');
diff --git a/src/lib/server/compute/index.worker.ts b/src/lib/server/compute/index.worker.ts
new file mode 100644
index 0000000..fbbaf7b
--- /dev/null
+++ b/src/lib/server/compute/index.worker.ts
@@ -0,0 +1,20 @@
+import type { ComputeBackend } from '@/lib/server/compute/types';
+import { WorkerComputeBackend } from '@/lib/server/compute/worker';
+
+let backendPromise: Promise<ComputeBackend> | null = null;
+
+export async function getCompute(): Promise<ComputeBackend> {
+  if (!backendPromise) {
+    backendPromise = Promise.resolve()
+      .then(() => new WorkerComputeBackend())
+      .catch((error) => {
+        backendPromise = null;
+        throw error;
+      });
+  }
+  return backendPromise;
+}
+
+export function isComputeAvailable(): boolean {
+  return true;
+}
diff --git a/src/lib/server/compute/local.ts b/src/lib/server/compute/local.ts
index c1f1475..41cea36 100644
--- a/src/lib/server/compute/local.ts
+++ b/src/lib/server/compute/local.ts
@@ -4,7 +4,7 @@ import { getTtsSegmentAudioObject } from '@/lib/server/tts/segments-blobstore';
 import {
   runPdfLayoutFromPdfBuffer,
   runWhisperAlignmentFromAudioBuffer,
-} from '@openreader/compute-core';
+} from '@openreader/compute-core/local-runtime';
 
 export class LocalComputeBackend implements ComputeBackend {
   readonly mode = 'local' as const;
diff --git a/src/lib/server/compute/types.ts b/src/lib/server/compute/types.ts
index f316756..4a5ce41 100644
--- a/src/lib/server/compute/types.ts
+++ b/src/lib/server/compute/types.ts
@@ -1,4 +1,4 @@
-import type { TTSAudioBuffer, TTSSentenceAlignment, ParsedPdfDocument } from '@openreader/compute-core';
+import type { TTSAudioBuffer, TTSSentenceAlignment, ParsedPdfDocument } from '@openreader/compute-core/contracts';
 
 export type ComputeMode = 'local' | 'worker';
 
diff --git a/src/lib/server/compute/worker-contract.ts b/src/lib/server/compute/worker-contract.ts
index b43cae9..a93c984 100644
--- a/src/lib/server/compute/worker-contract.ts
+++ b/src/lib/server/compute/worker-contract.ts
@@ -9,4 +9,4 @@ export {
   type WorkerJobState,
   type WorkerJobTiming,
   type WorkerJobStatusResponse,
-} from '@openreader/compute-core';
+} from '@openreader/compute-core/contracts';
diff --git a/tsconfig.json b/tsconfig.json
index 19d4e79..a06fb0d 100644
--- a/tsconfig.json
+++ b/tsconfig.json
@@ -20,7 +20,9 @@
     ],
     "paths": {
       "@/*": ["./src/*"],
-      "@openreader/compute-core": ["./compute/core/src/index.ts"]
+      "@openreader/compute-core": ["./compute/core/src/index.ts"],
+      "@openreader/compute-core/contracts": ["./compute/core/src/contracts.ts"],
+      "@openreader/compute-core/local-runtime": ["./compute/core/src/local-runtime.ts"]
     }
   },
   "include": ["next-env.d.ts", "**/*.ts", "**/*.tsx", ".next/types/**/*.ts"],