Show HN: A tool to safely migrate GitHub Actions workflows to Ubuntu-slim runner

Summary

Warning ubuntu-slim is currently in public preview and may change before general availability. Please review GitHub's official documentation for the latest updates and breaking changes. Tip 💡 Wait, couldn't you just copy-paste the following prompt into AI agent and skip using this tool altogether? 🤔😏 Spoiler alert: You'll be back. Goal: For every workflow file under ` .github/workflows ` , migrate jobs that currently run on ` ubuntu-latest ` to the container-based runner ` ubuntu-slim ` . Use the following decision rules in order when judging whether to migrate a job: 1 . Only consider jobs (including matrix entries) whose ` runs-on ` is ` ubuntu-latest ` or ` ubuntu-24.04 ` . 2 . Skip any job that uses service containers ( ` jobs.<job_id>.services ` ). 3 . Skip any job already running inside a container ( ` jobs.<job_id>.container ` ). 4 . Skip any job whose setup steps provision an environment that assumes a non-container host. 5 . Skip any job whose run scripts rely on host-only commands or elevated system privileges that containers cannot provide (e.g., ` systemctl ` , ` systemd ` , etc.). 6 . Skip any job whose execution time exceeds 15 minutes. Use the GitHub CLI to check the duration of the most recent successful run. Example commands: ``` bash # Get the database ID of the latest successful run id= $( gh run list \ --repo ${owner} / ${repo} \ --workflow ${workflow_file_name} \ --status success \ --limit 1 \ --json databaseId | jq . ' [0].databaseId ' ) # List jobs from that run to inspect start/completion times gh api \ repos/{owner}/{repo}/actions/runs/ ${id} /jobs | jq ' .jobs[] | {name: .name, started_at: .started_at, completed_at: .completed_at} ' Based on these rules, review each workflow and migrate every eligible job to ubuntu-slim. Afterward, report both the jobs that were successfully migrated and, for those that were not, the specific reasons they were ineligible. 🎯 Motivation GitHub Actions recently introduced the lightweight ubuntu-slim runner (1 ...