GitHub Codespaces

Intro

GitHub Codespaces is a cloud-based IDE powered by VS Code that lets you start coding instantly, either in your browser or in local VS Code, with no local setup required.

How it works

What are GitHub Codespaces?

Each codespace you create is hosted by GitHub in a Docker container, running on a virtual machine. You can choose from a selection of virtual machine types, from 2 cores, 8 GB RAM, and 32 GB storage, up to 32 cores, 128 GB RAM, and 128 GB storage.

• When you launch a Codespace, GitHub spins up a virtual machine (VM) in the cloud.
• Inside that VM, your project runs in a Docker container (defined by .devcontainer).
• The container holds all your dependencies, tools, and extensions.
• VS Code (browser or local) connects to this container so you can edit, build, and run code.

References

• GitHub Codespaces Docs
• Devcontainer
• GitHub Codespaces VS Code

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Setup

1. Open a repository in GitHub.
2. Click Code → Open with Codespaces → New codespace.
3. GitHub spins up a container with your project and dev tools.
4. Start coding immediately; all dependencies and environment settings can be preconfigured with .devcontainer.

Enable Clipboard Access in Firefox

To allow the GitHub Codespaces terminal to access the clipboard in Firefox, set dom.events.testing.asyncClipboard → true in about:config.

Devcontainer Basics

You can use devcontainer/devcontainer.json Lifecycle Scripts to define the container, tools, and startup commands.

• postCreateCommand: Runs once when the codespace is first created. Ideal for heavy installations like .
• postStartCommand: Runs every time the codespace is started (after it was stopped). Use this for starting development servers or background processes.
• postAttachCommand: Runs every time a user connects (attaches) to the codespace.

Example configuration

{
  "name": "My Project",
  "image": "://mcr.microsoft.com",
  "postCreateCommand": "npm install",
  "postStartCommand": "npm run start"
}

Related

• codespaces-integration