codespaces

GitHub Codespaces

Manage Codespaces entirely through gh codespace commands. Every command uses -c NAME to avoid interactive selection prompts.

Quick Reference

Operation	Command
Create	gh cs create -r OWNER/REPO -b BRANCH -m MACHINE --devcontainer-path PATH
List	gh cs list --json name,state,repository,createdAt
View details	gh cs view -c NAME --json name,state,machineName,lastUsedAt
SSH	gh cs ssh -c NAME
Run command	gh cs ssh -c NAME -- COMMAND
Stop	gh cs stop -c NAME
Delete	gh cs delete -c NAME
Logs	gh cs logs -c NAME
Rebuild	gh cs rebuild -c NAME
List ports	gh cs ports -c NAME --json label,sourcePort,visibility
Forward port	gh cs ports forward -c NAME LOCAL:REMOTE
Set secret	gh secret set KEY --user --app codespaces
List secrets	gh secret list --user --app codespaces

Machine Types

Name	Spec
basicLinux32gb	2-core, 8 GB RAM, 32 GB disk
standardLinux32gb	4-core, 16 GB RAM, 32 GB disk
premiumLinux	8-core, 32 GB RAM, 64 GB disk
largePremiumLinux	16-core, 64 GB RAM, 128 GB disk

Check available machines: gh cs create -r OWNER/REPO --show-status or gh api /repos/OWNER/REPO/codespaces/machines --jq '.machines[].name'

Codespace States

State	Meaning
Queued	Creation requested, waiting for resources
Provisioning	Building container
Available	Running, ready for SSH
ShuttingDown	Stopping in progress
Shutdown	Stopped (not billing for compute)
Rebuilding	Container rebuild in progress

Common Workflows

Create and connect

# Create — capture the name from JSON output
NAME=$(gh cs create -r OWNER/REPO -b main -m standardLinux32gb \
  --devcontainer-path .devcontainer/devcontainer.json \
  --json name -q .name)

# Wait for it to become available
while [ "$(gh cs view -c "$NAME" --json state -q .state)" != "Available" ]; do
  sleep 5
done

# Connect
gh cs ssh -c "$NAME"

Create for dotclaude

This repo has a devcontainer with Claude Code, mise, zsh, git-delta, and a network firewall.

NAME=$(gh cs create -r fairchild/dotclaude -b main -m standardLinux32gb \
  --devcontainer-path .devcontainer/devcontainer.json \
  --json name -q .name)

The container runs setup.sh post-create which:

• Installs mise runtimes from .mise.toml
• Installs Claude Code globally via npm
• Symlinks the workspace as ~/.claude
• Syncs Python dependencies with uv

The firewall (init-firewall.sh) restricts outbound traffic to:

• GitHub (API, web, git — via /meta CIDR ranges)
• npm registry, PyPI, Bun, mise, astral.sh
• Anthropic API, OpenAI API
• Sentry, Statsig (telemetry)

Set up secrets (before first create)

Secrets are injected as environment variables during creation.

# Required — Claude Code authentication
gh secret set ANTHROPIC_API_KEY --user --app codespaces

# Optional — image generation and integrations
gh secret set OPENAI_API_KEY --user --app codespaces

Debug creation failures

# Stream creation logs
gh cs logs -c NAME

# Common issues:
# - Missing secrets: set ANTHROPIC_API_KEY before creating
# - Firewall failures: init-firewall.sh needs NET_ADMIN capability
# - mise install hangs: check network access to mise.jdx.dev

Cost management

Codespaces bill for compute (running) and storage (existing). Minimize both.

# Stop when not in use
gh cs stop -c NAME

# Set idle timeout on create (default 30min)
gh cs create ... --idle-timeout 15m

# Set retention period (auto-delete after inactivity)
gh cs create ... --retention-period 72h

# Clean up old codespaces
gh cs list --json name,state,lastUsedAt | jq '.[] | select(.state == "Shutdown")'
gh cs delete -c NAME

Tips

• Always use --json + -q (jq filter) for machine-parseable output
• Capture the codespace name from create output — all subsequent commands need it
• gh cs ssh -c NAME -- claude to launch Claude Code directly
• Stop codespaces when done — compute billing stops, storage continues
• Delete codespaces you won't reuse — eliminates storage billing too
• Use --force with delete to skip confirmation