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gating-production-deploys

DevOps & Security
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Use when adding or editing a GitHub Actions workflow that pushes a container image to a registry (ECR/ghcr/Docker Hub via build-push-action) or dispatches a production deploy (a `commit_state_update` repository_dispatch to PostHog/charts). Those run from a single canonical deploy repo, gated by the CD_DEPLOY_ENABLED variable. Does NOT apply to workflows that publish GitHub releases, npm, crates, or Homebrew — those stay on the public repo.

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Source SKILL.md: https://github.com/PostHog/posthog/blob/HEAD/.agents/skills/gating-production-deploys/SKILL.md

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Gating production builds and deploys

Container-image pushes and Charts deploy dispatches run from one canonical deploy repo, selected by the CD_DEPLOY_ENABLED variable. Gate every such step or it publishes/deploys from the wrong place.

Gate these when they run on push-to-master / schedule / workflow_dispatch:

  • a prod-tag container image push, and
  • a commit_state_update dispatch to PostHog/charts (plus its deployer-token step).

Don't gate:

  • Release/distribution workflows — GitHub release, npm, crate, Homebrew (e.g. build-phrocs.yml, release-cli.yml). They publish from public; leave them.
  • pull_request / merge_group validation builds (gating them breaks contributor CI).
  • change-detection / setup jobs (use the org check only, not the variable).

The test is "pushes a prod image or triggers a deploy" — not "builds on master".

The gate

if: github.repository_owner == 'PostHog' && vars.CD_DEPLOY_ENABLED == 'true'

Use this instead of hardcoding github.repository == 'PostHog/posthog'.

Patterns

# whole job is the deploy/push (no PR builds) — gate the job:
if: github.repository_owner == 'PostHog' && vars.CD_DEPLOY_ENABLED == 'true'

# deploy job/step already keyed to master — add the gate:
if: github.repository_owner == 'PostHog' && vars.CD_DEPLOY_ENABLED == 'true' && github.ref == 'refs/heads/master'

# build job that also serves PRs — gate only the master arm of its `if`:
(github.event_name == 'push' && github.ref == 'refs/heads/master' && needs.changes.outputs.files == 'true'
  && github.repository_owner == 'PostHog' && vars.CD_DEPLOY_ENABLED == 'true')

# push step, master-only:
push: ${{ github.ref == 'refs/heads/master' && vars.CD_DEPLOY_ENABLED == 'true' }}
# push step, `push: true` (also pushes on PR for validation):
push: ${{ github.event_name == 'pull_request' || github.event_name == 'merge_group' || vars.CD_DEPLOY_ENABLED == 'true' }}

# reusable that pushes — add a `push` boolean input (default true), pass from caller:
#   with: { push: ${{ github.event_name == 'pull_request' || vars.CD_DEPLOY_ENABLED == 'true' }} }

Set CD_DEPLOY_ENABLED on the repo that should ship before merging, or master pushes skip the build/deploy. Lint with actionlint.

Examples: container-images-cd.yml (whole-job); cd-mcp-image.yml, livestream-docker-image.yml, cd-sandbox-base-image.yml (mixed PR+master); rust-docker-build.yml + _rust-build-images.yml (reusable push input). Counter-example, not gated: build-phrocs.yml.