Intermittently Using Wrong Version

[charlieoleary]

Hi,

Since we changed our Docker repository tags to be immutable I've noticed that intermittently Concourse / the semver resource will use the incorrect version between jobs in the pipeline. This ultimately leads to the build failing due to the tag being immutable. Here are some examples --

bump-version job starts and finishes successfully --

When we look at the job that includes the get for the version and the Docker build, we see that it's reusing the previous version --

Finally, when we look at the output itself, we see that the previous version (-rc.13) belongs to TWO builds, while (-rc.14) has no builds.

#16239 is using the duplicate tag.

Any idea what the root cause could be here? Most builds finish without an issue, but we will have some that end up with this version collision and are (correctly) blocked from overwriting the tag.