Link-edit resolves wrong module

Link-edit resolves wrong module is the pipeline telling you its own machinery is broken. Fix the factory before blaming the product.

What it means

• CI agents are the workers that run pipeline steps - an unavailable or misconfigured agent fails every job assigned to it.
• Dependency versions are a contract - one floating version can break a build that worked the day before.
• A pipeline without post-deployment verification only proves the files moved, not that the system works.

Common causes

• Build agent offline, out of disk, or missing a required tool such as the compiler or Zowe CLI.
• Dependency or plugin version drift: a new version pulled automatically that is incompatible.
• Emergency fix stuck behind a release approval gate designed for planned releases.
• No smoke test after deploy, so a bad deploy is discovered by users instead of the pipeline.
• Automated restart logic re-running a failed batch job that should have stayed failed for investigation.
• Alerts firing without the job name, return code, or log location needed to act on them.

How to diagnose

• Check agent status and capacity in the CI tool before re-running anything.
• Pin the dependency versions from the last good build and diff them against the failing one.
• Read the pipeline log at the first failed step - later steps fail as a consequence.
• Verify what the deploy step actually copied: file names, timestamps, and target libraries.
• Confirm whether the change record maps the real dependencies or just the headline change.

How to fix it

• Bring the agent back - disk space, service restart - or route the job to a healthy agent.
• Pin dependency versions; upgrade them deliberately, not automatically.
• Create a documented emergency lane in the approval process with the same audit trail.
• Add a post-deploy smoke test, one transaction or one batch step, that gates the release as done.
• Disable blind auto-restart for failed production work and require human review first.

Example: Smoke-test a deploy before calling it done

Submit one known-good job and watch its return code - the cheapest post-deployment verification there is.

Interview tip

• Q: Every build worked until this morning, and nobody changed the source. Link-edit resolves wrong module - where do you look?
• A: I look at what the pipeline pulls in automatically: dependency and plugin versions. I diff the resolved versions against the last green build and pin the one that moved. Unpinned dependencies are the usual suspect when the source has not changed.

Prevention checklist

• Pin all dependency versions and upgrade them on a schedule, not by surprise.
• Monitor agent health and disk space with alerts, not user complaints.
• Every deploy ends with an automated smoke test; a deploy is not done until it passes.
• Alerts must include the job name, return code, and where the log lives.