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devcontainer.md

Changed on 2026-04-27 15:11:30 EST

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 # Development containers
 
-> Learn about the Claude Code development container for teams that need consistent, secure environments.
+> Run Claude Code inside a dev container for consistent, isolated environments across your team.
 
-The reference [devcontainer setup](https://github.com/anthropics/claude-code/tree/main/.devcontainer) and associated [Dockerfile](https://github.com/anthropics/claude-code/blob/main/.devcontainer/Dockerfile) offer a preconfigured development container that you can use as is, or customize for your needs. This devcontainer works with the Visual Studio Code [Dev Containers extension](https://code.visualstudio.com/docs/devcontainers/containers) and similar tools.
+A [development container](https://containers.dev/), or dev container, lets you define an identical, isolated environment that every engineer on your team can run. With Claude Code installed in that container, commands Claude runs execute inside it rather than on the host machine, while edits to your project files appear in your local repository as you work.
 
-The container's enhanced security measures (isolation and firewall rules) allow you to run `claude --dangerously-skip-permissions` to bypass permission prompts for unattended operation.
+This page covers [installing Claude Code in a dev container](#add-claude-code-to-your-dev-container) and the configuration topics that follow. Each topic is self-contained, so jump to the ones that match what you need to set up:
+
+* [Persist authentication and settings across rebuilds](#persist-authentication-and-settings-across-rebuilds)
+* [Enforce organization policy](#enforce-organization-policy)
+* [Restrict network egress](#restrict-network-egress)
+* [Run without permission prompts](#run-without-permission-prompts)
 
 <Warning>
-  While the devcontainer provides substantial protections, no system is completely immune to all attacks.
-  When executed with `--dangerously-skip-permissions`, devcontainers don't prevent a malicious project from exfiltrating anything accessible in the devcontainer including Claude Code credentials.
-  We recommend only using devcontainers when developing with trusted repositories.
-  Always maintain good security practices and monitor Claude's activities.
+  While the dev container provides substantial protections, no system is completely immune to all attacks.
+  When executed with `--dangerously-skip-permissions`, dev containers do not prevent a malicious project from exfiltrating anything accessible inside the container, including the Claude Code credentials stored in [`~/.claude`](/en/claude-directory).
+  Only use dev containers when developing with trusted repositories, and monitor Claude's activities.
+  Avoid mounting host secrets such as `~/.ssh` or cloud credential files into the container; prefer repository-scoped or short-lived tokens.
 </Warning>
 
-## Key features
+<Accordion title="How dev containers work with your editor">
+  <img src="https://mintcdn.com/claude-code/YvJyjZfd9yMihr0i/images/devcontainer-architecture.svg?fit=max&auto=format&n=YvJyjZfd9yMihr0i&q=85&s=9017b1d16a446c6cc37ba562f35b9aae" className="dark:hidden" alt="Diagram showing an editor on the host connecting to a Docker dev container. Claude Code, the terminal, and build tools run inside the container. The host repository is bind-mounted into the container as the workspace." width="640" height="300" data-path="images/devcontainer-architecture.svg" />
 
-* **Production-ready Node.js**: Built on Node.js 20 with essential development dependencies
-* **Security by design**: Custom firewall restricting network access to only necessary services
-* **Developer-friendly tools**: Includes git, ZSH with productivity enhancements, fzf, and more
-* **Seamless VS Code integration**: Pre-configured extensions and optimized settings
-* **Session persistence**: Preserves command history and configurations between container restarts
-* **Works everywhere**: Compatible with macOS, Windows, and Linux development environments
+  <img src="https://mintcdn.com/claude-code/YvJyjZfd9yMihr0i/images/devcontainer-architecture-dark.svg?fit=max&auto=format&n=YvJyjZfd9yMihr0i&q=85&s=ef00c8e25b1ea7a3a152895f1488831b" className="hidden dark:block" alt="Diagram showing an editor on the host connecting to a Docker dev container. Claude Code, the terminal, and build tools run inside the container. The host repository is bind-mounted into the container as the workspace." width="640" height="300" data-path="images/devcontainer-architecture-dark.svg" />
 
-## Getting started in 4 steps
+  A dev container runs as a Docker container, either on your machine or on a cloud host such as GitHub Codespaces. An editor that supports the Dev Containers spec, such as VS Code, GitHub Codespaces, a JetBrains IDE, or Cursor, connects to that container: you browse and edit files in the editor as usual, but the integrated terminal, language servers, and build tools all run inside the container rather than on your host. Editors without dev container support, such as plain Vim, are not part of this workflow.
 
-1. Install VS Code and the [Dev Containers extension](https://marketplace.visualstudio.com/items?itemName=ms-vscode-remote.remote-containers)
-2. Clone the [Claude Code reference implementation](https://github.com/anthropics/claude-code/tree/main/.devcontainer) repository
-3. Open the repository in VS Code
-4. When prompted, click "Reopen in Container" (or use Command Palette: Cmd+Shift+P → "Dev Containers: Reopen in Container")
+  Claude Code runs inside the container, so it sees the same files, dependencies, and tools as the rest of your project's toolchain. In VS Code you can use either the [Claude Code extension panel](/en/vs-code) or run `claude` in the integrated terminal; both run inside the container and share the same `~/.claude` configuration.
+</Accordion>
 
-Once the container finishes building, open a terminal in VS Code with `` Ctrl+` `` and run `claude` to authenticate and start your first session. The container has Claude Code preinstalled, so you can begin working immediately. Your project files are mounted into the container, and any code Claude writes appears in your local repository.
+## Add Claude Code to your dev container
 
-## Configuration breakdown
+Claude Code installs into any dev container through the [Claude Code Dev Container Feature](https://github.com/anthropics/devcontainer-features/tree/main/src/claude-code).
 
-The devcontainer setup consists of three primary components:
+The settings work with any tool that supports the Dev Containers spec, such as VS Code, GitHub Codespaces, or JetBrains IDEs. The steps below use VS Code as an example.
 
-* [**devcontainer.json**](https://github.com/anthropics/claude-code/blob/main/.devcontainer/devcontainer.json): Controls container settings, extensions, and volume mounts
-* [**Dockerfile**](https://github.com/anthropics/claude-code/blob/main/.devcontainer/Dockerfile): Defines the container image and installed tools
-* [**init-firewall.sh**](https://github.com/anthropics/claude-code/blob/main/.devcontainer/init-firewall.sh): Establishes network security rules
+When you open the container in VS Code or Codespaces, the feature also adds the Claude Code VS Code extension; other editors ignore that part.
 
-## Security features
+<Tip>
+  New to dev containers? The [VS Code Dev Containers tutorial](https://code.visualstudio.com/docs/devcontainers/tutorial) walks through installing Docker, the extension, and opening your first container. For a fuller hardened example with a firewall and persistent volumes, see [Try the reference container](#try-the-reference-container).
+</Tip>
 
-The container implements a multi-layered security approach with its firewall configuration:
+<Steps>
+  <Step title="Create or update devcontainer.json">
+    Save the following as `.devcontainer/devcontainer.json` in your repository, or add the `features` block to your existing file.
 
-* **Precise access control**: Restricts outbound connections to whitelisted domains only (npm registry, GitHub, Claude API, etc.)
-* **Allowed outbound connections**: The firewall permits outbound DNS and SSH connections
-* **Default-deny policy**: Blocks all other external network access
-* **Startup verification**: Validates firewall rules when the container initializes
-* **Isolation**: Creates a secure development environment separated from your main system
+    The version tag at the end, such as `:1.0`, pins the feature's install script, not the Claude Code release. The feature installs the latest Claude Code, and Claude Code auto-updates itself inside the container by default.
 
-## Customization options
+    To pin the CLI version or disable auto-update, see [Enforce organization policy](#enforce-organization-policy).
 
-The devcontainer configuration is designed to be adaptable to your needs:
+    ```json .devcontainer/devcontainer.json theme={null}
+    {
+      "image": "mcr.microsoft.com/devcontainers/base:ubuntu",
+      "features": {
+        "ghcr.io/anthropics/devcontainer-features/claude-code:1.0": {}
+      }
+    }
+    ```
 
-* Add or remove VS Code extensions based on your workflow
-* Modify resource allocations for different hardware environments
-* Adjust network access permissions
-* Customize shell configurations and developer tooling
+    Replace the `image` line with your project's base image or remove it if your existing file uses a Dockerfile.
+  </Step>
 
-## Example use cases
+  <Step title="Rebuild the container">
+    Open the VS Code Command Palette with `Cmd+Shift+P` on Mac or `Ctrl+Shift+P` on Windows and Linux, and run **Dev Containers: Rebuild Container**.
 
-### Secure client work
+    For other tools, follow that tool's rebuild action: see [rebuilding in GitHub Codespaces](https://docs.github.com/en/codespaces/developing-in-a-codespace/rebuilding-the-container-in-a-codespace), the [Dev Containers CLI](https://github.com/devcontainers/cli), or your IDE's dev container documentation.
+  </Step>
 
-Use devcontainers to isolate different client projects, ensuring code and credentials never mix between environments.
+  <Step title="Sign in to Claude Code">
+    Open a terminal in the rebuilt container and run `claude`, then follow the authentication prompt.
+  </Step>
+</Steps>
 
-### Team onboarding
+What you see at the authentication prompt depends on your provider:
 
-New team members can get a fully configured development environment in minutes, with all necessary tools and settings pre-installed.
+* **Anthropic**: sign in through a browser with your Claude or Anthropic Console account
+* **[Amazon Bedrock, Google Vertex AI, or Microsoft Foundry](/en/third-party-integrations)**: Claude Code uses your cloud provider credentials, with no browser prompt
 
-### Consistent CI/CD environments
+For cloud providers, pass credentials into the container as environment variables through `containerEnv`, a Codespaces secret, or your cloud's workload identity rather than mounting credential files from the host. See [Amazon Bedrock](/en/amazon-bedrock), [Google Vertex AI](/en/google-vertex-ai), or [Microsoft Foundry](/en/microsoft-foundry) for the credential chain Claude Code reads.
 
-Mirror your devcontainer configuration in CI/CD pipelines to ensure development and production environments match.
+See [Choose your API provider](/en/admin-setup#choose-your-api-provider) to decide which path fits your organization.
 
-## Related resources
+<Note>
+  If the browser sign-in completes but the callback never reaches the container, copy the code shown in the browser and paste it at the `Paste code here if prompted` prompt in the terminal. This can happen when the editor's port forwarding doesn't route the localhost callback.
+</Note>
 
-* [VS Code devcontainers documentation](https://code.visualstudio.com/docs/devcontainers/containers)
-* [Claude Code security best practices](/en/security)
-* [Enterprise network configuration](/en/network-config)
+## Persist authentication and settings across rebuilds
+
+By default, the container's home directory is discarded on rebuild, so engineers must sign in again each time. Claude Code stores its authentication token, user settings, and session history under [`~/.claude`](/en/claude-directory). Mount a named volume at that path to keep this state across rebuilds.
+
+The following example mounts a volume at the home directory of the `node` user:
+
+```json devcontainer.json theme={null}
+"mounts": [
+  "source=claude-code-config,target=/home/node/.claude,type=volume"
+]
+```
+
+Replace `/home/node` with the home directory of your container's `remoteUser`. If you mount the volume somewhere other than `~/.claude`, set [`CLAUDE_CONFIG_DIR`](/en/env-vars) to the mount path so Claude Code reads and writes there.
+
+To isolate state per project rather than sharing one volume across all repositories, include the `${devcontainerId}` variable in the source name. The [reference configuration](https://github.com/anthropics/claude-code/blob/main/.devcontainer/devcontainer.json) uses `source=claude-code-config-${devcontainerId}` for this purpose.
+
+In GitHub Codespaces, `~/.claude` persists across stopping and starting a codespace, but is still cleared when you rebuild the container, so the volume mount above applies there too. To carry authentication across codespaces, store `ANTHROPIC_API_KEY` or a `CLAUDE_CODE_OAUTH_TOKEN` from [`claude setup-token`](/en/authentication#generate-a-long-lived-token) as a [Codespaces secret](https://docs.github.com/en/codespaces/managing-your-codespaces/managing-your-account-specific-secrets-for-github-codespaces); Codespaces makes secrets available as environment variables inside the container automatically.
+
+## Enforce organization policy
+
+A dev container is a convenient place to apply organization policy, because the same image and configuration run on every engineer's machine.
+
+Claude Code reads `/etc/claude-code/managed-settings.json` on Linux and applies it at the highest precedence in the [settings hierarchy](/en/settings#how-scopes-interact), so values there override anything an engineer sets in `~/.claude` or the project's `.claude/` directory. Copy the file into place from your Dockerfile:
+
+```dockerfile Dockerfile theme={null}
+RUN mkdir -p /etc/claude-code
+COPY managed-settings.json /etc/claude-code/managed-settings.json
+```
+
+Because the Dockerfile lives in the repository, anyone with write access can change or remove this step. For policy that engineers cannot bypass by editing repository files, deliver managed settings through [server-managed settings](/en/server-managed-settings) or your MDM instead. See [managed settings files](/en/settings#settings-files) for the available keys and the other delivery paths.
+
+To set [environment variables](/en/env-vars) that apply to every Claude Code session in the container, add them to `containerEnv` in your `devcontainer.json`. The following example opts out of telemetry and error reporting and prevents Claude Code from auto-updating after install:
+
+```json devcontainer.json theme={null}
+"containerEnv": {
+  "CLAUDE_CODE_DISABLE_NONESSENTIAL_TRAFFIC": "1",
+  "DISABLE_AUTOUPDATER": "1"
+}
+```
+
+The Dev Container Feature always installs the latest Claude Code release. To pin a specific Claude Code version for reproducible builds, install it from your Dockerfile with `npm install -g @anthropic-ai/claude-code@X.Y.Z` instead of using the feature, and set `DISABLE_AUTOUPDATER` as shown above.
+
+For the full list of policy controls including permission rules, tool restrictions, and MCP server allowlists, see [Set up Claude Code for your organization](/en/admin-setup).
+
+To make [MCP servers](/en/mcp) available inside the container, define them at [project scope](/en/mcp#mcp-installation-scopes) in a `.mcp.json` file at the repository root so they are checked in alongside your dev container configuration. Install any binaries that local stdio servers depend on in your Dockerfile, and add remote server domains to your network allowlist.
+
+## Restrict network egress
+
+You can limit the container's outbound traffic to only the domains Claude Code needs. See [Network access requirements](/en/network-config#network-access-requirements) for the inference and authentication domains, and [Telemetry services](/en/data-usage#telemetry-services) for the optional telemetry and error reporting connections and how to disable them.
+
+The reference container includes an [`init-firewall.sh`](https://github.com/anthropics/claude-code/blob/main/.devcontainer/init-firewall.sh) script that blocks all outbound traffic except the domains Claude Code and your development tools need. Running a firewall inside a container requires extra permissions, so the reference adds the `NET_ADMIN` and `NET_RAW` capabilities through `runArgs`. The firewall script and these capabilities are not required for Claude Code itself: you can leave them out and rely on your own network controls instead.
+
+## Run without permission prompts
+
+Because the container runs Claude Code as a non-root user and confines command execution to the container, you can pass `--dangerously-skip-permissions` for unattended operation. The CLI rejects this flag when launched as root, so confirm `remoteUser` is set to a non-root account.
+
+Skipping permission prompts removes your opportunity to review tool calls before they run. Claude can still modify any file in the bind-mounted workspace, which appears directly on your host, and reach anything the container's network policy allows. Pair this flag with the [network egress restrictions](#restrict-network-egress) above to limit what a bypassed session can reach.
+
+If you want fewer prompts without disabling safety checks, consider [auto mode](/en/permission-modes#eliminate-prompts-with-auto-mode) instead, which has a classifier review actions before they run. To prevent engineers from using `--dangerously-skip-permissions` at all, set `permissions.disableBypassPermissionsMode` to `"disable"` in [managed settings](/en/settings#permission-settings).
+
+## Try the reference container
+
+The [`anthropics/claude-code`](https://github.com/anthropics/claude-code/tree/main/.devcontainer) repository includes an example dev container that combines the CLI, the egress firewall, persistent volumes, and a Zsh-based shell. It is provided as a working example rather than a maintained base image; use it to see how the pieces fit together before applying them to your own configuration.
+
+<Steps>
+  <Step title="Install prerequisites">
+    Install VS Code and the [Dev Containers extension](https://marketplace.visualstudio.com/items?itemName=ms-vscode-remote.remote-containers).
+  </Step>
+
+  <Step title="Clone the reference">
+    Clone the [Claude Code repository](https://github.com/anthropics/claude-code) and open it in VS Code.
+  </Step>
+
+  <Step title="Reopen in container">
+    When prompted, click **Reopen in Container**, or run **Dev Containers: Reopen in Container** from the Command Palette.
+  </Step>
+
+  <Step title="Start Claude Code">
+    Once the container finishes building, open a terminal with `` Ctrl+` `` and run `claude` to sign in and start your first session.
+  </Step>
+</Steps>
+
+To use this configuration with your own project, copy the `.devcontainer/` directory into your repository and adjust the Dockerfile for your toolchain, or return to [Add Claude Code to your dev container](#add-claude-code-to-your-dev-container) to add only the feature to a setup you already have.
+
+The reference configuration consists of three files. None of them are required when you add Claude Code to your own dev container through the feature, but they show one way to combine the pieces.
+
+| File                                                                                                       | Purpose                                                                       |
+| ---------------------------------------------------------------------------------------------------------- | ----------------------------------------------------------------------------- |
+| [`devcontainer.json`](https://github.com/anthropics/claude-code/blob/main/.devcontainer/devcontainer.json) | Volume mounts, `runArgs` capabilities, VS Code extensions, and `containerEnv` |
+| [`Dockerfile`](https://github.com/anthropics/claude-code/blob/main/.devcontainer/Dockerfile)               | Base image, development tools, and the Claude Code install                    |
+| [`init-firewall.sh`](https://github.com/anthropics/claude-code/blob/main/.devcontainer/init-firewall.sh)   | Blocks all outbound network traffic except the allowed domains                |
+
+## Next steps
+
+Once Claude Code is running in your dev container, the pages below cover the rest of an organization rollout: choosing an authentication path, delivering managed policy outside the repository, monitoring usage, and understanding what Claude Code stores and sends.
+
+* [Set up Claude Code for your organization](/en/admin-setup): choose an authentication provider, decide how policy reaches devices, and plan the rollout
+* [Server-managed settings](/en/server-managed-settings): deliver managed policy from the Claude.ai admin console so engineers cannot bypass it by editing repository files
+* [Monitor usage and audit activity](/en/monitoring-usage): export OpenTelemetry metrics and review what your team is running
+* [Network access requirements](/en/network-config#network-access-requirements): the full domain allowlist for proxies and firewalls
+* [Telemetry services and opt-out](/en/data-usage#telemetry-services): what Claude Code sends by default and the environment variables that disable it
+* [Explore the `.claude` directory](/en/claude-directory): what the volume mount holds, including credentials, settings, and session history
+* [Security model](/en/security): how Claude Code's permission system, sandboxing, and prompt-injection protections fit together
+* [Permission modes](/en/permission-modes): the full range from plan mode to auto mode to bypass, and when to use each