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: [
“@nuxtjs/i18n”,
“@nuxtjs/sitemap”,
“@nuxt/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:white_check_mark: 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