devcontainer

name	devcontainer
description	DevContainer runtimes, CLI tools, and version parity with Dagger

Skill: DevContainer

VS Code docs: Developing inside a Container

The DevContainer is defined in .devcontainer/ and is the canonical development environment for this repo. Opening the repo in VS Code triggers a prompt to reopen in the container, which builds the image and mounts the workspace at /workspace.

The main repo is mounted from your local computer, so files changes persist across devcontainer reboots. It also means credentials for tools like Git or Claude Code can be injected so you don't have to re-auth every time.

Goal: every runtime, CLI tool, and script alias needed for development must be available immediately after the container starts, with no manual setup steps.

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What the DevContainer provides

Tool

Tool	Purpose	Notes
Node.js	JS runtime	Version pinned via ARG NODE_VERSION in Dockerfile
pnpm	Package management	Version pinned via ARG PNPM_VERSION
Go	Golang runtime (primarily used by Dagger)	Version pinned via ARG GO_VERSION; also installs gopls
Dagger CLI	Mirror CI execution locally	Version pinned via ARG DAGGER_VERSION
Docker	docker-outside-of-docker devcontainer feature	Shares the host Docker socket — required to run Dagger
Brew	Package management for CLI tools	Useful for installing some of the other tools, should rarely be required outside devcontainer setup
Nx	Monorepo task runner	Available after running pnpm i
Local Scripts	Complicated combos of tasks in a single command	/workspace/scripts/commands is on PATH, exposing these shortcuts

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Version parity: DevContainer ↔ Dagger

The Dagger CI pipeline runs in its own container — it does not use the DevContainer image. Versions are specified separately in two places and must be kept in sync:

Runtime	DevContainer	Dagger
Node.js	ARG NODE_VERSION in .devcontainer/Dockerfile	nodeVersion in dagger/test-and-build/main.go and dagger/modules/pnpm/main.go
pnpm	ARG PNPM_VERSION in .devcontainer/Dockerfile	pnpmVersion in dagger/test-and-build/main.go
dagger	ARG DAGGER_VERSION in .devcontainer/Dockerfile	engineVersion in each dagger.json
Debian	base image tag in .devcontainer/Dockerfile (debian13)	DefaultVersion() in dagger/modules/debian/main.go ("13.3")

When upgrading a runtime version, update all locations in the table above. A mismatch means dagger-test runs under a different Node/pnpm version than local development — bugs that only reproduce in CI are a common symptom.