Generate Devcontainer Configuration

Devcontainer Setup Skill generates a complete, pre-configured devcontainer for a project - Claude Code plus language-specific tooling - by detecting the project's language stack and writing five files into .devcontainer/: a Dockerfile, devcontainer.json, a post_install.py setup script, a .zshrc, and an install.sh helper that adds a devc CLI command. Its base template already bundles Claude Code (with the anthropics/skills, trailofbits/skills, and trailofbits/skills-curated marketplace plugins), Python 3.13 via uv, Node 22 via fnm, ast-grep, network-isolation tooling (iptables/ipset with NET_ADMIN), and modern CLI tools like ripgrep, fd, fzf, tmux, and git-delta.

Use it when a user asks to set up a devcontainer or wants a sandboxed, persistent Claude Code development environment. It is explicitly not for modifying an already-existing devcontainer config, for general Docker questions unrelated to devcontainers, or for building production containers - this generates development environments only.

Input: the project directory, from which it infers a project name - checking package.json's name, pyproject.toml's project.name, Cargo.toml's package.name, go.mod's module path, or the directory name, in that order, then slugifying it - and detects the language stack from marker files: Python (pyproject.toml, *.py), Node/TypeScript (package.json, tsconfig.json), Rust (Cargo.toml), Go (go.mod/go.sum). For multi-language projects it configures all detected languages, Python first via the Dockerfile, the rest via devcontainer features, chaining every setup step into one postCreateCommand. Output: language-specific customization layered onto the base template - for Python, ruff/Pylance extensions and a uv sync postCreateCommand; for Node, ESLint/Prettier extensions and a postCreateCommand that adapts to the detected lockfile (pnpm, yarn, npm ci, or npm install); for Rust, the rust:1 devcontainer feature, rust-analyzer, and cargo build --locked when a Cargo.lock exists; for Go, the go:1 feature, the Go extension, and go mod download.

RUN uv python install <version> --default

Before presenting the result, it validates that every {{PROJECT_NAME}}/{{PROJECT_SLUG}} placeholder is substituted, the devcontainer.json is valid JSON, all detected languages' extensions are present, and postCreateCommand chains every required step with &&.

Draws on the devcontainers feature ecosystem (ghcr.io/devcontainers/features/rust:1, .../go:1) for Rust and Go, uv and fnm for fast Python and Node installs, and VS Code's devcontainer customizations schema for extensions and settings; persistent state such as a Cargo or Go module cache is added via named Docker volumes keyed to the project slug.

Developers who want a working, sandboxed devcontainer - matched to their project's actual language stack, with Claude Code and sensible editor defaults already configured - generated automatically rather than hand-written per project.