diff --git a/src/app/api/tts/segments/ensure/route.ts b/src/app/api/tts/segments/ensure/route.ts
index aa80c1e..e16c084 100644
--- a/src/app/api/tts/segments/ensure/route.ts
+++ b/src/app/api/tts/segments/ensure/route.ts
@@ -150,6 +150,11 @@ async function deleteEntryIfUnused(userId: string, segmentEntryId: string): Prom
 export async function POST(request: NextRequest) {
   let didCreateDeviceIdCookie = false;
   let deviceIdToSet: string | null = null;
+  let computeBackendPromise: ReturnType<typeof getCompute> | null = null;
+  const getComputeBackend = async () => {
+    if (!computeBackendPromise) computeBackendPromise = getCompute();
+    return computeBackendPromise;
+  };
   try {
     if (!isS3Configured()) return s3NotConfiguredResponse();
 
@@ -372,7 +377,8 @@ export async function POST(request: NextRequest) {
         // previously unavailable, retry alignment using the current segment text.
         if (!alignment) {
           try {
-            const aligned = (await getCompute().alignWords({
+            const computeBackend = await getComputeBackend();
+            const aligned = (await computeBackend.alignWords({
               audioObjectKey: existing.audioKey,
               text: segment.text,
             })).alignments;
@@ -523,7 +529,8 @@ export async function POST(request: NextRequest) {
         let alignment: TTSSegmentManifestItem['alignment'] = null;
         try {
           const whisperBytes = Uint8Array.from(persistedBuffer);
-          const aligned = (await getCompute().alignWords({
+          const computeBackend = await getComputeBackend();
+          const aligned = (await computeBackend.alignWords({
             audioBuffer: whisperBytes.buffer,
             audioObjectKey: audioKey,
             text: segment.text,
diff --git a/src/lib/server/compute/index.ts b/src/lib/server/compute/index.ts
index 4424f1f..5442429 100644
--- a/src/lib/server/compute/index.ts
+++ b/src/lib/server/compute/index.ts
@@ -2,21 +2,23 @@ import type { ComputeBackend, ComputeMode } from '@/lib/server/compute/types';
 import { isComputeModeAvailable, readComputeMode } from '@/lib/server/compute/mode';
 import { WorkerComputeBackend } from '@/lib/server/compute/worker';
 
-let backend: ComputeBackend | null = null;
+let backendPromise: Promise<ComputeBackend> | null = null;
 
-function createBackend(): ComputeBackend {
+async function createBackend(): Promise<ComputeBackend> {
   const mode: ComputeMode = readComputeMode();
   if (mode === 'worker') return new WorkerComputeBackend();
-  // Intentionally lazy-load local compute to avoid tracing heavy ONNX
-  // dependencies unless the backend is actually local.
-  // eslint-disable-next-line @typescript-eslint/no-require-imports
-  const { LocalComputeBackend } = require('@/lib/server/compute/local') as typeof import('@/lib/server/compute/local');
+  const { LocalComputeBackend } = await import('@/lib/server/compute/local');
   return new LocalComputeBackend();
 }
 
-export function getCompute(): ComputeBackend {
-  if (!backend) backend = createBackend();
-  return backend;
+export async function getCompute(): Promise<ComputeBackend> {
+  if (!backendPromise) {
+    backendPromise = createBackend().catch((error) => {
+      backendPromise = null;
+      throw error;
+    });
+  }
+  return backendPromise;
 }
 
 export function isComputeAvailable(): boolean {
diff --git a/src/lib/server/jobs/parsePdfJob.ts b/src/lib/server/jobs/parsePdfJob.ts
index 1410949..c64cea9 100644
--- a/src/lib/server/jobs/parsePdfJob.ts
+++ b/src/lib/server/jobs/parsePdfJob.ts
@@ -28,7 +28,8 @@ export async function parsePdfJob(input: ParsePdfJobInput): Promise<void> {
       .set({ parseStatus: 'running' })
       .where(and(eq(documents.id, input.documentId), eq(documents.userId, input.userId)));
 
-    const parsed = await getCompute().parsePdfLayout({
+    const compute = await getCompute();
+    const parsed = await compute.parsePdfLayout({
       documentId: input.documentId,
       namespace: input.namespace,
       documentObjectKey: documentKey(input.documentId, input.namespace),