Issue Summary
Experiencing consistent deployment failures on Vercel where builds complete successfully but deployments hang indefinitely at the "Deploying outputs..." phase, eventually timing out after 20+ minutes with "An unexpected error happened when running this build."
Project Details
- Framework: Nuxt 3.17.4 with Nitro 2.11.12
- Project Type: SSR application with multilingual support
- Build Output: ~40MB (12.7MB gzipped)
- Regions Tested: sfo1, iad1, cdg1 - all exhibit same behavior
Evidence This Is a Platform Issue
- Successful Build Phase
[23:30:00.287] Build Completed in /vercel/output [2m] ✅ Client built in 11.459ms ✅ Server built in 8000ms ✅ Nitro server built successfully ✅ Total build time: ~2 minutes
- Deployment Phase Failure
[23:30:00.559] Deploying outputs... [Hangs for 6+ minutes] ❌ Build Failed: "An unexpected error happened when running this build"
- Regression Test Proves Platform Issue
- Tested with commit 9249a5b that was previously deploying successfully
- Same hanging behavior occurs, confirming this is NOT a code issue
- No code changes between working and non-working states
Deployment Attempts Timeline
| Attempt | Region | Build Result | Deployment Result | Duration | |---------|--------|----------------|-------------------------------|--- -----------| | 1 | cdg1 | ✅ Success (2m) | ❌ Hang at "Deploying outputs" | 20m+ timeout | | 2 | sfo1 | ✅ Success (2m) | ❌ Hang at "Deploying outputs" | 20m+ timeout | | 3 | iad1 | ✅ Success (2m) | ❌ Hang at "Deploying outputs" | 20m+ timeout |
Configuration Details
export default defineNuxtConfig({ ssr: true, nitro: { preset: "vercel", experimental: { wasm: true }, esbuild: { options: { target: "node18" } }, compressPublicAssets: true, prerender: { crawlLinks: false, routes: [], ignore: ["/dashboard/", "/api/dashboard/", "/auth/**"], }, }, modules: [ "/i18n", "/sitemap", "/image", "nuxt-gtag", // ... other modules ], // Build-time database query with proper timeout handling // (works fine locally and in Vercel build phase) }) Troubleshooting Attempted
✅ Tried different CLI versions: 42.3.0, 44.2.7✅ Tested multiple regions: sfo1, iad1, cdg1✅ Used deployment flags: --force, --no-cache, --debug✅ Verified with working commit: Same issue persists✅ Checked bundle size: Within reasonable limits (40MB total)✅ Tested build locally: Completes successfully in ~10 seconds
Error Pattern
- Upload Phase: ✅ Completes successfully
- Build Phase: ✅ Completes successfully (2 minutes)
- Deploy Phase: ❌ Hangs at "Deploying outputs..." indefinitely
- Final Result: "An unexpected error happened when running this build"
Request for Investigation
This appears to be a Vercel platform infrastructure issue affecting the deployment phase specifically. The fact that:
- Builds complete successfully
- Previously working commits now fail identically
- Multiple regions exhibit the same behavior
- Status page shows "operational" but deployments are failing
Suggests an issue with Vercel's deployment infrastructure rather than user code.
Has Anyone Else Experienced This?
Looking for others who may have encountered similar issues with deployments hanging at the "Deploying outputs..." phase, and any potential workarounds while waiting for a platform fix.
Project affected: Nuxt 3 SSR applicationsTimeframe: Started [when you first noticed]Impact: Production deployments completely blocked