CDN cache invalidation strategy documented; deployment process includes CDN purge or auto-purge configured

Deploying new code without purging the CDN cache means users may receive stale assets — old JavaScript bundles, outdated HTML, broken references to renamed files — for hours or days after a deployment. ISO 25010 reliability.maturity requires that deployments deliver what was deployed. Without a documented invalidation strategy or automated purge step in the CI/CD pipeline, cache staleness is the default outcome, not the exception, and debugging it requires correlating CDN access logs rather than a simple cache clear.

Add a CDN cache purge step to your deployment workflow. For Cloudflare in GitHub Actions:

# .github/workflows/deploy.yml
- name: Deploy to production
  run: npm run deploy:prod

- name: Purge Cloudflare cache
  run: |
    curl -s -X POST \
      "https://api.cloudflare.com/client/v4/zones/${{ secrets.CF_ZONE_ID }}/purge_cache" \
      -H "Authorization: Bearer ${{ secrets.CF_API_TOKEN }}" \
      -H "Content-Type: application/json" \
      -d '{"purge_everything": true}'

For content-hashed assets (Next.js default), purge is less critical because filenames change with each build — but HTML and API responses still need invalidation. Document the purge command and the required secrets in DEPLOYMENT.md.