Testing dev container configuration changes on a prebuild-enabled branch - GitHub Docs Skip to main content GitHub Docs Version: Free, Pro, & Team Search or ask Copilot Search or ask Copilot Select language: current language is English Search or ask Copilot Search or ask Copilot Open menu Collapse sidebar Expand sidebar Scroll breadcrumbs left * Home * Codespaces * Prebuilding your codespaces * Test dev container changes Scroll breadcrumbs right Codespaces * * * Quickstart * Getting started * What are Codespaces? * Codespaces features * The codespace lifecycle * Deep dive into Codespaces * Developing in a codespace * Develop in a codespace * Create a codespace for a repo * Create a codespace from a template * Delete a codespace * Open an existing codespace * Work collaboratively * Source control * Pull requests * Stop a codespace * Forward ports * Rebuilding a container * Default environment variables * Persist variables and files * Connecting to a private network * Machine learning * Visual Studio Code * GitHub CLI * Customizing your codespace * Rename a codespace * Change your shell * Change the machine type * Setting your user preferences * Personalize your codespaces * Set the default editor * Set the default region * Set the timeout * Configure automatic deletion * Choose the host image * Setting up your project * Adding a dev container configuration * Introduction to dev containers * Setting up a Node.js project * Setting up a C# (.NET) project * Setting up a Java project * Setting up a PHP project * Setting up a Python project * Configuring dev containers * Set a minimum machine spec * Adding features * Automatically opening files * Specifying recommended secrets * Setting up your repository * Facilitating codespace creation * Set up a template repo * Prebuilding your codespaces * About prebuilds * Configure prebuilds * Allow external repo access * Manage prebuilds * Test dev container changes * Managing your codespaces * Codespaces secrets * Repository access * Security logs * GPG verification * Managing your organization * Enable or disable Codespaces * Billing and ownership * List organization codespaces * Manage Codespaces costs * Manage secrets * Audit logs * Restrict machine types * Restrict codespace creation * Restrict base image * Restrict port visibility * Restrict timeout periods * Restrict the retention period * Reference * Access a private registry * Copilot in Codespaces * VS Code Command Palette * Security in Codespaces * Disaster recovery * Troubleshooting * Codespaces logs * Codespaces clients * Included usage * Exporting changes * Creation and deletion * Authenticating to repositories * Connection * Codespaces prebuilds * Personalization * Port forwarding * GPG verification * Working with support * github.dev editor Testing dev container configuration changes on a prebuild-enabled branch When you change the dev container configuration for a branch that's enabled for prebuilds, you should test your changes in a codespace. Who can use this feature? People with write permissions to a repository can create or edit the dev container configuration for a branch. Copy as Markdown Any changes you make to the dev container configuration for a prebuild-enabled branch will result in an update to the codespace configuration and the associated prebuild. It’s therefore important to test such changes in a codespace from a test branch before committing your changes to a branch of your repository that's actively used. This will ensure you’re not introducing breaking changes for your team. For more information, see Introduction to dev containers . Testing changes to the dev container configuration * Create a codespace from the prebuild-enabled branch whose dev container you want to change. For more information, see Creating a codespace for a repository . * In the codespace, check out a test branch. For more information, see Using source control in your codespace . * Make the required changes to the dev container configuration. * Apply the changes by rebuilding the container. For more information, see Introduction to dev containers . * After everything looks good, we also recommend creating a new codespace from your test branch to ensure everything is working. You can then commit your changes to your repository's default branch or an active feature branch, triggering an update of the prebuild for that branch. Note Creating this codespace will take longer than usual because it will not be created from a prebuild. Back to top Help and support Was this Doc helpful? Yes No Help us make GitHub Docs great! All Docs are open source. See something that's wrong or unclear? Submit a pull request. Make a contribution Still need help? Provide GitHub Feedback Contact support Expert services Blog GitHub Inc. © 2026 Terms Privacy Status Pricing