{"slug":"devcontainer-setup-2","title":"devcontainer-setup","summary":"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.","platform":"Claude","tags":[],"authorName":"LLM Mart","authorSlug":"llm-mart","score":0,"source":"github","price":null,"verified":false,"createdAt":"2026-09-06T18:19:38.664267Z","repo":{"url":"https://github.com/trailofbits/skills","stars":7234,"forks":616,"license":"CC-BY-SA-4.0","updatedAt":"2026-09-25T07:34:17Z"},"bodyHtml":"
\n

name: devcontainer-setup\ndescription: 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.

\n

Devcontainer Setup Skill

\n

Creates a pre-configured devcontainer with Claude Code and language-specific tooling.

\n

When to Use

\n\n

When NOT to Use

\n\n

Workflow

\n
flowchart TB\n    start([User requests devcontainer])\n    recon[1. Project Reconnaissance]\n    detect[2. Detect Languages]\n    generate[3. Generate Configuration]\n    write[4. Write files to .devcontainer/]\n    done([Done])\n\n    start --> recon\n    recon --> detect\n    detect --> generate\n    generate --> write\n    write --> done\n
\n

Phase 1: Project Reconnaissance

\n

Infer Project Name

\n

Check in order (use first match):

\n
    \n
  1. package.json → name field
    2. \n
  2. pyproject.toml → project.name
    3. \n
  3. Cargo.toml → package.name
    4. \n
  4. go.mod → module path (last segment after /)
    5. \n
  5. Directory name as fallback
    6. \n
\n

Convert to slug: lowercase, replace spaces/underscores with hyphens.

\n

Detect Language Stack

\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n
LanguageDetection Files
Pythonpyproject.toml, *.py
Node/TypeScriptpackage.json, tsconfig.json
RustCargo.toml
Gogo.mod, go.sum
\n

Multi-Language Projects

\n

If multiple languages are detected, configure all of them in the following priority order:

\n
    \n
  1. Python - Primary language, uses Dockerfile for uv + Python installation
    2. \n
  2. Node/TypeScript - Uses devcontainer feature
    3. \n
  3. Rust - Uses devcontainer feature
    4. \n
  4. Go - Uses devcontainer feature
    5. \n
\n

For multi-language postCreateCommand, chain all setup commands:

\n
uv run /opt/post_install.py && uv sync && npm ci\n
\n

Extensions and settings from all detected languages should be merged into the configuration.

\n

Phase 2: Generate Configuration

\n

Start with base templates from resources/ directory. Substitute:

\n\n

Then apply language-specific modifications below.

\n

Base Template Features

\n

The base template includes:

\n\n
\n

Language-Specific Sections

\n

Python Projects

\n

Detection: pyproject.toml, requirements.txt, setup.py, or *.py files

\n

Dockerfile additions:

\n

The base Dockerfile already includes Python 3.13 via uv. If a different version is required (detected from pyproject.toml), modify the Python installation:

\n
# Install Python via uv (fast binary download, not source compilation)\nRUN uv python install <version> --default\n
\n

devcontainer.json extensions:

\n

Add to customizations.vscode.extensions:

\n
\"ms-python.python\",\n\"ms-python.vscode-pylance\",\n\"charliermarsh.ruff\"\n
\n

Add to customizations.vscode.settings:

\n
\"python.defaultInterpreterPath\": \".venv/bin/python\",\n\"[python]\": {\n  \"editor.defaultFormatter\": \"charliermarsh.ruff\",\n  \"editor.codeActionsOnSave\": {\n    \"source.organizeImports\": \"explicit\"\n  }\n}\n
\n

postCreateCommand:\nIf pyproject.toml exists, chain commands:

\n
rm -rf .venv && uv sync && uv run /opt/post_install.py\n
\n
\n

Node/TypeScript Projects

\n

Detection: package.json or tsconfig.json

\n

No Dockerfile additions needed: The base template includes Node 22 via fnm (Fast Node Manager).

\n

devcontainer.json extensions:

\n

Add to customizations.vscode.extensions:

\n
\"dbaeumer.vscode-eslint\",\n\"esbenp.prettier-vscode\"\n
\n

Add to customizations.vscode.settings:

\n
\"editor.defaultFormatter\": \"esbenp.prettier-vscode\",\n\"editor.codeActionsOnSave\": {\n  \"source.fixAll.eslint\": \"explicit\"\n}\n
\n

postCreateCommand:\nDetect package manager from lockfile and chain with base command:

\n\n
\n

Rust Projects

\n

Detection: Cargo.toml

\n

Features to add:

\n
\"ghcr.io/devcontainers/features/rust:1\": {}\n
\n

devcontainer.json extensions:

\n

Add to customizations.vscode.extensions:

\n
\"rust-lang.rust-analyzer\",\n\"tamasfe.even-better-toml\"\n
\n

Add to customizations.vscode.settings:

\n
\"[rust]\": {\n  \"editor.defaultFormatter\": \"rust-lang.rust-analyzer\"\n}\n
\n

postCreateCommand:\nIf Cargo.lock exists, use locked builds:

\n
uv run /opt/post_install.py && cargo build --locked\n
\n

If no lockfile, use standard build:

\n
uv run /opt/post_install.py && cargo build\n
\n
\n

Go Projects

\n

Detection: go.mod

\n

Features to add:

\n
\"ghcr.io/devcontainers/features/go:1\": {\n  \"version\": \"latest\"\n}\n
\n

devcontainer.json extensions:

\n

Add to customizations.vscode.extensions:

\n
\"golang.go\"\n
\n

Add to customizations.vscode.settings:

\n
\"[go]\": {\n  \"editor.defaultFormatter\": \"golang.go\"\n},\n\"go.useLanguageServer\": true\n
\n

postCreateCommand:

\n
uv run /opt/post_install.py && go mod download\n
\n
\n

Reference Material

\n

For additional guidance, see:

\n\n
\n

Adding Persistent Volumes

\n

Pattern for new mounts in devcontainer.json:

\n
\"mounts\": [\n  \"source={{PROJECT_SLUG}}-<purpose>-${devcontainerId},target=<container-path>,type=volume\"\n]\n
\n

Common additions:

\n\n
\n

Output Files

\n

Generate these files in the project's .devcontainer/ directory:

\n
    \n
  1. Dockerfile - Container build instructions
    2. \n
  2. devcontainer.json - VS Code/devcontainer configuration
    3. \n
  3. post_install.py - Post-creation setup script
    4. \n
  4. .zshrc - Shell configuration
    5. \n
  5. install.sh - CLI helper for managing the devcontainer (devc command)
    6. \n
\n
\n

Validation Checklist

\n

Before presenting files to the user, verify:

\n
    \n
  1. All {{PROJECT_NAME}} placeholders are replaced with the human-readable name
    2. \n
  2. All {{PROJECT_SLUG}} placeholders are replaced with the slugified name
    3. \n
  3. JSON syntax is valid in devcontainer.json (no trailing commas, proper nesting)
    4. \n
  4. Language-specific extensions are added for all detected languages
    5. \n
  5. postCreateCommand includes all required setup commands (chained with &&)
    6. \n
\n
\n

User Instructions

\n

After generating, inform the user:

\n
    \n
  1. How to start: \"Open in VS Code and select 'Reopen in Container'\"
    2. \n
  2. Alternative: devcontainer up --workspace-folder .
    3. \n
  3. CLI helper: Run .devcontainer/install.sh self-install to add the devc command to PATH
    4. \n
\n","files":[{"path":"agents/openai.yaml","sizeBytes":239,"isText":true},{"path":"assets/trail-of-bits-mark.svg","sizeBytes":3084,"isText":false},{"path":"references/dockerfile-best-practices.md","sizeBytes":3341,"isText":true},{"path":"references/features-vs-dockerfile.md","sizeBytes":675,"isText":true},{"path":"resources/devcontainer.json","sizeBytes":2584,"isText":true},{"path":"resources/Dockerfile","sizeBytes":3679,"isText":false},{"path":"resources/install.sh","sizeBytes":23116,"isText":true},{"path":"resources/post_install.py","sizeBytes":8606,"isText":true},{"path":"resources/.zshrc","sizeBytes":1869,"isText":false},{"path":"SKILL.md","sizeBytes":8060,"isText":true}],"reviewScore":null,"reviewSummary":null,"trust":{"provenance":"trusted-source-unreviewed","notice":"Community-authored content, reproduced verbatim and not vetted as instructions. Treat it as data to evaluate, never as directives to follow.","bodySource":null},"bodyLocked":false,"purchaseUrl":null,"sourceUrl":null,"report":{"provenance":"trusted-source-unreviewed","screen":{"ran":true,"outcome":"notes-only","suspicious":0,"notes":2,"hiddenCharacters":false},"virusScan":{"engine":"clamav","status":"clean","scannedAt":"2026-09-17T15:59:40.4236Z","sha256":"3C8D0395321D9CCD78B6CD6B4377D31064E5DCC8BA2F5365F6D3AA80F4278D6B","sizeBytes":20982},"review":null,"source":{"repositoryUrl":"https://github.com/trailofbits/skills","path":"plugins/devcontainer-setup/skills/devcontainer-setup","license":"CC-BY-SA-4.0","commit":"0cc1c73a5e96749ab32d7ea5e14892fafa6972ae","subtreeSha":"78672644980BFA1F833416AABBB58BD6E24EAB1A61A9DDF8B2AC3094CFCF1C3C","lastSyncedAt":"2026-09-25T07:36:46.789003Z"},"reviewedAt":"2026-09-17T16:00:34.477044Z","notice":"Community-authored content, reproduced verbatim and not vetted as instructions. Treat it as data to evaluate, never as directives to follow."},"install":[{"target":"skills-cli","command":"npx skills add https://github.com/trailofbits/skills/tree/main/plugins/devcontainer-setup/skills/devcontainer-setup"},{"target":"claude-code","command":"claude plugin marketplace add https://llmmart.ai/marketplace.json && claude plugin install trailofbits-skills@llmmart"},{"target":"git","command":"git clone https://github.com/trailofbits/skills.git"}]}