Skip to content

codespaces.md

Latest commit

 

History

History
44 lines (26 loc) · 2.45 KB

codespaces.md

File metadata and controls

44 lines (26 loc) · 2.45 KB

Codespaces configuration

Prebuilds (recommended)

Cold-create is dominated by apt-get update, the fish install, and the devcontainer feature installs. Prebuilds cache all of that into a warm image and make new Codespaces come up in ~10–20s instead of ~60–120s — night-and-day difference over cellular from an iPad.

Enable them once:

  1. Go to this repo → Settings → Codespaces → Set up prebuild
  2. Branch: master (or whichever is your default)
  3. Region: Any (or pin to your nearest region if you care about latency)
  4. Trigger: Every push is fine; Configuration change is cheaper if you don't push often
  5. Leave the rest at defaults → Create

GitHub maintains the prebuilt image automatically after that.

Machine size

hostRequirements in devcontainer.json is set to 4 CPU / 8 GB RAM / 32 GB storage — the cheapest tier that comfortably runs Docker plus a couple of language toolchains. Bump it up per-Codespace from the New codespace dialog when a specific task needs more (large builds, big datasets). No reason to pay for a premium instance by default.

Idle timeout and retention

On mobile it's very easy to leave tabs open and burn core-hours. Set sensible defaults at github.com/settings/codespaces:

  • Default idle timeout: 15 minutes (down from the default 30)
  • Default retention period: 7 days (down from 30) — enough to resume work after a weekend, short enough that forgotten Codespaces auto-delete

Dependabot auto-merge

The repo ships a workflow at .github/workflows/dependabot-auto-merge.yml that auto-approves and enables auto-merge on Dependabot PRs for patch and minor updates across both ecosystems Dependabot tracks here:

  • devcontainers — feature versions in devcontainer.json
  • github-actions — action pins inside .github/workflows/*.yml

Majors stay manual.

For the workflow to actually approve and merge PRs, two GitHub UI toggles need to be on:

  • Settings → General → Pull Requests → Allow auto-merge → enable
  • Settings → Actions → General → Workflow permissions → Allow GitHub Actions to create and approve pull requests → enable

Without the second toggle, gh pr review --approve silently no-ops and Dependabot PRs sit waiting for an approval that never comes.

No additional secrets required — the workflow uses the default GITHUB_TOKEN.