EAS Android builds suddenly failing with Sentry source map upload throwing HTTP 503 only during chunk upload (assemble succeeds)

[kashyapjagwani1]

Hello everyone,

Since yesterday (Dec 8-9 2025), all of our EAS Android production builds have been failing consistently during the Sentry source map upload step with a 503, even though everything worked perfectly for months before.

• Expo SDK: 53.0.24
• @sentry/react-native: 6.14.0

What happens

1. Bundle + source map are generated correctly
2. Debug ID is injected
3. GET /organizations/{org}/chunk-upload/ → 200 OK
4. POST /organizations/{org}/artifactbundle/assemble/ → 200 OK, returns missingChunks list
5. ~2 minutes later → final failure with
   error: API request failed ... unknown error (http status: 503)

Rate limits are fine (remaining 39/40, concurrent 24/25).
iOS builds succeed.
Setting SENTRY_ALLOW_FAILURE=true makes the build pass (so the rest of the build is healthy).
Retrying the exact same commit multiple times and Android builds fail.

This feels like a transient backend issue on the US upload endpoint specifically for artifact bundle chunk uploads.
Has anyone else seen this spike in the last 24-48 hours?
Is there a known incident on the ingest/upload cluster for us.sentry.io?

Any help will be appreciated?🙏🏻