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Keep version fields in YAML files in sync without losing comments

· 2 min read
Erik Osterman
Erik Osterman
Founder @ Cloud Posse

A Helm values file, a docker-compose override, or any other hand-maintained YAML config often carries one field that tracks an external dependency's version, alongside comments explaining what the surrounding settings do and anchors sharing config between sections. Keeping that one field in sync usually means either editing it by hand on every release, or running it through a full parse-and- regenerate step that throws the comments and anchors away.

The Problem​

The Version Tracker's template manager covers YAML by treating a *.tmpl source as the source of truth and rendering it to a sibling output file — a good fit when the whole file is generated, but overkill for a hand-maintained file that only has one or two managed fields. The marker manager can annotate a line with a comment, but its rewrite is a plain token substitution, not an assignment into structured YAML. Neither manager patches a single field in an existing, hand-authored YAML document while leaving everything else — comments, anchors, key order — untouched.

The Fix​

A new yaml file manager writes locked values directly into YAML files at configured field paths. It reuses Atmos's own format-preserving YAML editor — the same engine behind atmos config set and atmos stack set — so comments, anchors and aliases, and key order on untouched fields all survive the edit.

How to Use It​

version:
  dependencies:
    cli:
      ecosystem: github/releases
      datasource: github-releases
      provider: github
      package: cli/cli
      desired: "~2"

  files:
    - manager: yaml
      paths:
        - charts/*/values.yaml
      options:
        set:
          - path: version
            from: cli
            format: '{{ trimPrefix "v" .Version }}'

atmos version track apply rewrites the configured field from the lock, stripping the v prefix GitHub tags carry via the optional format template; --check fails and lists any file that's out of date, so CI can catch drift before it merges.

Get Involved​

See the Version Files docs for the full path syntax and the format field. Have feedback on this feature? Open an issue or join the conversation in the Cloud Posse community Slack.