TeamCity snapshot dependency failed / build chain not started in CI
In a build chain, a snapshot dependency links builds to the same sources. When a dependency build fails, TeamCity by default does not start the dependent build, so the whole chain stops with a dependency error.
What this error means
The dependent build shows "Dependency failed" or "Snapshot dependency ... failed to start" and does not run, because an upstream build in the chain failed or was canceled.
Build failed to start: snapshot dependency "App / Build" failed.
Dependency build "Build #542" finished with status FAILURE.Common causes
An upstream build in the chain failed
A snapshot dependency requires its source build to succeed; when it fails, the default option prevents the dependent build from starting.
The dependency could not start at all
The upstream build never ran (no compatible agent, canceled, or VCS error), leaving the dependent build blocked.
How to fix it
Fix and re-run the failed upstream build
- Open the build chain and find the failed dependency build.
- Diagnose and fix that build (its own step, test, or infra failure).
- Re-run the chain; the dependent build starts once the dependency succeeds.
Adjust the dependency start option deliberately
In the snapshot dependency options, choose whether to run the dependent build even if the dependency fails, only when it succeeds, or to fail the whole chain, per your intent.
How to prevent it
- Keep upstream builds in a chain reliable, since they gate everything downstream.
- Set snapshot dependency options to match how you want failures to propagate.
- Monitor the build chain, not just individual configurations.