cnb-pipeline

Define the structure as branch, event, pipeline, stage, then job. Specify a Docker image or Dockerfile build, list stages with scripts or built-in task types, and optionally add failStages and endStages. Always validate the file with the schema validator before committing.

Run cnb pulls get-ci-logs to automatically locate the failed build and retrieve its logs. Classify the failure as a code error, configuration issue, or external service problem based on log keywords, then fix the root cause and push without polling for CI status.

CNB provides 82 built-in variables prefixed with CNB_, including CNB_BRANCH, CNB_COMMIT, CNB_BUILD_ID, CNB_TOKEN, and CNB_PIPELINE_KEY. Custom variables must not use the CNB_ prefix, as it is reserved for system read-only variables.

Common causes include YAML indentation with tabs, misspelled field names, non-built-in CNB_ prefixed variables, built-in tasks used under unsupported events, and repository-level events like tag_push placed outside the $ fallback branch.

Yes. Use YAML anchors within the same file for template inheritance with merge support, and use !reference to import values from other files included via the include directive. Keys starting with a dot serve as reference sources and are not treated as branch names.

Analyze stage durations from build logs, then add Docker volume caches for dependencies, preinstall system packages via a custom Dockerfile instead of apt install, parallelize independent jobs, and use ifModify to skip unchanged modules in monorepos.