devcontainer

A development container configuration targeting Coder. It can be built at workspace-start time with envbuilder, or pulled as a prebuilt inner image by envbox.

Published image

Every push to main publishes a multi-platform image for linux/amd64 and linux/arm64 to:

ghcr.io/unusualvibes/devcontainer:latest

Pull requests build both platforms without publishing them. Version tags such as v1.2.3 additionally publish 1.2.3 and 1.2, and every published build gets a sha-... tag. Use a version or SHA tag instead of latest when reproducibility matters.

The first published package may be private. In the repository's package settings, make it public for unauthenticated Kubernetes pulls, or configure an imagePullSecret on the workspace Pod.

For the Coder envbox template, replace the inner-image environment variable with:

env {
  name  = "CODER_INNER_IMAGE"
  value = "ghcr.io/unusualvibes/devcontainer:latest"
}

What's inside

Base: Ubuntu Noble (24.04)

Layer	Tools
Languages	Go 1.24.3, Rust (stable), Python 3, Node.js 22
Go tools	gopls, dlv, goimports, golangci-lint
Rust tools	clippy, rustfmt, rust-src, cargo-watch
Python tools	uv, ruff, black, mypy, pytest, ipython
Node globals	claude-code, codex
Shell	zsh + Starship prompt, tmux + tpm
Extras	vim, rsync, jq, openssh-client/server, iproute2

VS Code / code-server extensions: Claude Code, Go, Rust Analyzer, Python + Black + Pylint, Git Graph, GitLens, Code Spell Checker.

envbuilder notes

Coder's envbuilder builds the image from this repo's Dockerfile at workspace-start time. A few things differ from a standard devcontainer setup:

• VS Code customizations are applied manually. envbuilder does not inject customizations.vscode into code-server's user-data directory, so postStartCommand runs apply-vscode-customizations to merge settings and install extensions on every start.
• SSH host keys are regenerated at start time by the same script (ssh-keygen -A).
• No Docker socket is required. envbuilder handles image building inside the Coder workspace.

Environment variables

Set these in your host shell (or Coder template) before starting the workspace:

Variable	Purpose
ANTHROPIC_API_KEY	Passed into the container for Claude Code
OPENAI_API_KEY	Passed into the container for Codex

Telemetry and auto-updates for Claude Code are disabled by default (CLAUDE_CODE_DISABLE_TELEMETRY=1, DISABLE_AUTOUPDATER=1). Remove those lines from devcontainer.json if you want them enabled.

Persistent storage

Claude Code auth and configuration are stored in a named Docker volume (claude-code-config-<devcontainerId>) mounted at /home/coder/.claude, so credentials survive container rebuilds.

Build arguments

The Dockerfile exposes these ARGs if you need to pin different versions:

ARG	Default
UBUNTU_VERSION	noble
GO_VERSION	1.24.3
RUST_VERSION	stable
NODE_VERSION	22

User-level installs

User tools (Rust toolchain, Go binaries, npm globals, Python tools, Starship, tmux plugins) are installed in parallel during the Docker build via cgr, a dependency-aware command runner. The install graph lives in .devcontainer/install.cgr.