Creates devcontainers with Claude Code, language-specific tooling (Python/Node/Rust/Go), and persistent volumes. Use when adding devcontainer support to a project, setting up isolated development envi
The skill file stays in the publisher's repository.
Paste the copied command in a terminal. It installs this SKILL.md into that agent.
npx skills add trailofbits/skills --skill devcontainer-setup -a cursor -y
Creates devcontainers with Claude Code, language-specific tooling (Python/Node/Rust/Go), and persistent volumes. Use when adding devcontainer support to a project, setting up isolated development environments, or configuring sandboxed Claude Code workspaces.
Creates devcontainers with Claude Code, language-specific tooling (Python/Node/Rust/Go), and persistent volumes. Use when adding devcontainer support to a project, setting up isolated development environments, or configuring sandboxed Claude Code workspaces.
Creates a pre-configured devcontainer with Claude Code and language-specific tooling.
flowchart TB
start([User requests devcontainer])
recon[1. Project Reconnaissance]
detect[2. Detect Languages]
generate[3. Generate Configuration]
write[4. Write files to .devcontainer/]
done([Done])
start --> recon
recon --> detect
detect --> generate
generate --> write
write --> done
Check in order (use first match):
package.json → name fieldpyproject.toml → project.nameCargo.toml → package.namego.mod → module path (last segment after /)Convert to slug: lowercase, replace spaces/underscores with hyphens.
| Language | Detection Files |
|---|---|
| Python | pyproject.toml, *.py |
| Node/TypeScript | package.json, tsconfig.json |
| Rust | Cargo.toml |
| Go | go.mod, go.sum |
If multiple languages are detected, configure all of them in the following priority order:
For multi-language postCreateCommand, chain all setup commands:
uv run /opt/post_install.py && uv sync && npm ci
Extensions and settings from all detected languages should be merged into the configuration.
Start with base templates from resources/ directory. Substitute:
{{PROJECT_NAME}} → Human-readable name (e.g., "My Project"){{PROJECT_SLUG}} → Slug for volumes (e.g., "my-project")Then apply language-specific modifications below.
The base template includes:
.devcontainer/ mounted read-only to prevent container escapeCLAUDE_CODE_OAUTH_TOKEN and ANTHROPIC_API_KEY via remoteEnvDetection: pyproject.toml, requirements.txt, setup.py, or *.py files
Dockerfile additions:
The base Dockerfile already includes Python 3.13 via uv. If a different version is required (detected from pyproject.toml), modify the Python installation:
# Install Python via uv (fast binary download, not source compilation)
RUN uv python install <version> --default
devcontainer.json extensions:
Add to customizations.vscode.extensions:
"ms-python.python",
"ms-python.vscode-pylance",
"charliermarsh.ruff"
Add to customizations.vscode.settings:
"python.defaultInterpreterPath": ".venv/bin/python",
"[python]": {
"editor.defaultFormatter": "charliermarsh.ruff",
"editor.codeActionsOnSave": {
"source.organizeImports": "explicit"
}
}
postCreateCommand:
If pyproject.toml exists, chain commands:
rm -rf .venv && uv sync && uv run /opt/post_install.py
Detection: package.json or tsconfig.json
No Dockerfile additions needed: The base template includes Node 22 via fnm (Fast Node Manager).
devcontainer.json extensions:
Add to customizations.vscode.extensions:
"dbaeumer.vscode-eslint",
"esbenp.prettier-vscode"
Add to customizations.vscode.settings:
"editor.defaultFormatter": "esbenp.prettier-vscode",
"editor.codeActionsOnSave": {
"source.fixAll.eslint": "explicit"
}
postCreateCommand: Detect package manager from lockfile and chain with base command:
pnpm-lock.yaml → uv run /opt/post_install.py && pnpm install --frozen-lockfileyarn.lock → uv run /opt/post_install.py && yarn install --frozen-lockfilepackage-lock.json → uv run /opt/post_install.py && npm ciuv run /opt/post_install.py && npm installDetection: Cargo.toml
Features to add:
"ghcr.io/devcontainers/features/rust:1": {}
devcontainer.json extensions:
Add to customizations.vscode.extensions:
"rust-lang.rust-analyzer",
"tamasfe.even-better-toml"
Add to customizations.vscode.settings:
"[rust]": {
"editor.defaultFormatter": "rust-lang.rust-analyzer"
}
postCreateCommand:
If Cargo.lock exists, use locked builds:
uv run /opt/post_install.py && cargo build --locked
If no lockfile, use standard build:
uv run /opt/post_install.py && cargo build
Detection: go.mod
Features to add:
"ghcr.io/devcontainers/features/go:1": {
"version": "latest"
}
devcontainer.json extensions:
Add to customizations.vscode.extensions:
"golang.go"
Add to customizations.vscode.settings:
"[go]": {
"editor.defaultFormatter": "golang.go"
},
"go.useLanguageServer": true
postCreateCommand:
uv run /opt/post_install.py && go mod download
For additional guidance, see:
references/dockerfile-best-practices.md - Layer optimization, multi-stage builds, architecture supportreferences/features-vs-dockerfile.md - When to use devcontainer features vs custom DockerfilePattern for new mounts in devcontainer.json:
"mounts": [
"source={{PROJECT_SLUG}}-<purpose>-${devcontainerId},target=<container-path>,type=volume"
]
Common additions:
source={{PROJECT_SLUG}}-cargo-${devcontainerId},target=/home/vscode/.cargo,type=volume (Rust)source={{PROJECT_SLUG}}-go-${devcontainerId},target=/home/vscode/go,type=volume (Go)Generate these files in the project's .devcontainer/ directory:
Dockerfile - Container build instructionsdevcontainer.json - VS Code/devcontainer configurationpost_install.py - Post-creation setup script.zshrc - Shell configurationinstall.sh - CLI helper for managing the devcontainer (devc command)Before presenting files to the user, verify:
{{PROJECT_NAME}} placeholders are replaced with the human-readable name{{PROJECT_SLUG}} placeholders are replaced with the slugified namedevcontainer.json (no trailing commas, proper nesting)postCreateCommand includes all required setup commands (chained with &&)After generating, inform the user:
devcontainer up --workspace-folder ..devcontainer/install.sh self-install to add the devc command to PATH