If you're anything like me, your feed is full of people saying Claude Code can do everything. Maybe it can. But I was reluctant to just run the usual one-line install (like npm install -g @anthropic-ai/claude-code), which puts Claude Code directly on your computer, and hand an AI agent the same access my terminal has — every file, every folder, every login. I wanted Claude on a leash. The answer turned out to be a Dev Container: Claude Code runs inside a Docker container, and it can only see the folders you explicitly hand it. I expected a headache. It took about 20 minutes.

Step 1 · WSL 2. Docker Desktop on Windows runs Linux containers through the Windows Subsystem for Linux. Open PowerShell and install it (or check that you already have version 2):

wsl --install     # first-time install (restart when prompted)
wsl --version     # confirm WSL version 2.x

Step 2 · Docker Desktop. Install Docker Desktop, open it, and wait for Engine running in the bottom-left corner. Then test it:

docker run hello-world

You should see "Hello from Docker! This message shows that your installation appears to be working correctly." and a new hello-world container listed under Containers in the Docker dashboard. (Want to poke around a full Linux container? Try docker run -it ubuntu bash, and exit to leave.)

Check: WSL integration is on

In Docker Desktop, go to Settings → Resources → WSL integration. Make sure Enable integration with my default WSL distro is checked (and toggle on Ubuntu if it's listed), then click Apply & restart.

Step 3 · Install the extension. In VS Code, open Extensions (Ctrl+Shift+X), search Dev Containers, and install the one published by Microsoft.

Step 4 · Clone the repo. Anthropic's claude-code repository ships a ready-made .devcontainer folder — a Dockerfile with Claude Code installed, plus a firewall script. Press Win+R, type wt to open Windows Terminal, and run:

git clone https://github.com/anthropics/claude-code.git
cd claude-code
code .

Step 5 · Reopen in Container. VS Code notices the .devcontainer folder and shows a pop-up: "Folder contains a Dev Container configuration file." Click Reopen in Container. The first build downloads and builds the image, so give it a few minutes.

Claude Code is already installed in the container. In the VS Code terminal, just type:

claude

Your login is saved in a Docker volume mounted at /home/node/.claude, so it survives container rebuilds.

Right now Claude can only see the claude-code repo. To work on your own projects, share them into the container with a bind mount. Open .devcontainer/devcontainer.json and add one line per folder to the "mounts" array:

Here is my setup as an example. I mount natchayal.github.io, the repo I use to build this personal website, and the screenshots in the rest of this tutorial show that repo. Replace it with whichever repo you want to work on.

"mounts": [
  "source=claude-code-bashhistory-${devcontainerId},target=/commandhistory,type=volume",
  "source=claude-code-config-${devcontainerId},target=/home/node/.claude,type=volume",
  "source=C:/Users/nluan/OneDrive/Documents/GitHub/natchayal.github.io,target=/workspace/natchayal.github.io,type=bind"
],

In the last line, change source= to the full path of your repo on your computer, and change the end of target= from natchayal.github.io to your repo’s folder name. Keep the two volume lines as they are.

Save the file. VS Code shows "Configuration file(s) changed … The container might need to be rebuilt" — click Rebuild. If the pop-up doesn't appear, press Ctrl+Shift+P (Cmd+Shift+P on Mac), run Dev Containers: Rebuild Container, and press Enter.

After the rebuild, your project shows up in the Explorer under /workspace/your-repo-name (in my example, /workspace/natchayal.github.io), and you can cd into it from the terminal.

Move into the mounted project and start Claude there, so it treats that folder as its workspace:

cd natchayal.github.io
claude

Confirm the trust prompt for the new folder, then ask for something. My first test was:

Claude read my About and home pages, wrote an intro, and edited README.md. Because the folder is a bind mount, the change lands in the real file on my computer. I reviewed the diff in GitHub Desktop and committed it; if I hadn't liked it, discarding the change would have put the file back.

A sandbox doesn't help much if a second copy of Claude Code is still logged in on your host machine. To switch over completely, run these in a normal (non-container) terminal, using only the lines that match how you originally installed it:

npm uninstall -g @anthropic-ai/claude-code

Remove-Item -Recurse -Force "$env:USERPROFILE\.claude"
Remove-Item -Force "$env:USERPROFILE\.claude.json"

rm -rf ~/.claude ~/.claude.json

Instead of having access to every folder on my computer, Claude now has access only to the folders I mount. That's a big improvement, but it isn't magic. Know where the edges are:

Within those limits, the same approach works for other coding agents too, like Codex CLI or Copilot CLI: give each one a container, mount only what it needs, and review its changes before you commit. If you have questions, feel free to reach out. Happy (safe) Clauding!