Development Environment

This document will help you set up your development environment and understand how to work with the codebase. Whether you're fixing bugs, adding features, or just exploring the code, this guide will get you started.

Prerequisites

Before you begin, make sure you have the following installed:

1. Git - For version control
2. Node.js (version v20.18.1 or higher recommended) and npm
3. Visual Studio Code - Our recommended IDE for development

Getting Started

Installation

1. Fork and Clone the Repository:

   • Fork the Repository:
     • Visit the Kilo Code GitHub repository
     • Click the "Fork" button in the top-right corner to create your own copy.
   • Clone Your Fork:

     git clone https://github.com/[YOUR-USERNAME]/kilocode.git
     cd kilocode
     Replace [YOUR-USERNAME] with your actual GitHub username.

2. Install dependencies:

   pnpm install

   This command will install dependencies for the main extension, webview UI, and e2e tests.

3. Install VSCode Extensions:

   • Required: ESBuild Problem Matchers - Helps display build errors correctly.

While not strictly necessary for running the extension, these extensions are recommended for development:

• ESLint - Integrates ESLint into VS Code.
• Prettier - Code formatter - Integrates Prettier into VS Code.

The full list of recommended extensions is here

Project Structure

The project is organized into several key directories:

• src/ - Core extension code
  • core/ - Core functionality and tools
  • services/ - Service implementations
• webview-ui/ - Frontend UI code
• e2e/ - End-to-end tests
• scripts/ - Utility scripts
• assets/ - Static assets like images and icons

Development Workflow

Building the Extension

To build the extension:

pnpm build

This will:

1. Build the webview UI
2. Compile TypeScript
3. Bundle the extension
4. Create a .vsix file in the bin/ directory

Running the Extension

To run the extension in development mode:

1. Press F5 (or select Run → Start Debugging) in VSCode
2. This will open a new VSCode window with Kilo Code loaded

Hot Reloading

• Webview UI changes: Changes to the webview UI will appear immediately without restarting
• Core extension changes: Changes to the core extension code will automatically reload the ext host

In development mode (NODE_ENV="development"), changing the core code will trigger a workbench.action.reloadWindow command, so it is no longer necessary to manually start/stop the debugger and tasks.

Important: In production builds, when making changes to the core extension, you need to:

1. Stop the debugging process
2. Kill any npm tasks running in the background (see screenshot below)
3. Start debugging again

Installing the Built Extension

To install your built extension:

code --install-extension "$(ls -1v bin/kilo-code-*.vsix | tail -n1)"

Replace [version] with the current version number.

Testing

Kilo Code uses several types of tests to ensure quality:

Unit Tests

Run unit tests with:

npm test

This runs both extension and webview tests.

To run specific test suites:

npm run test:extension  # Run only extension tests
npm run test:webview    # Run only webview tests

End-to-End Tests

E2E tests verify the extension works correctly within VSCode:

1. Create a .env.local file in the root with required API keys:

   OPENROUTER_API_KEY=sk-or-v1-...

2. Run the integration tests:

   npm run test:integration

For more details on E2E tests, see e2e/VSCODE_INTEGRATION_TESTS.md.

Linting and Type Checking

Ensure your code meets our quality standards:

npm run lint          # Run ESLint
npm run check-types   # Run TypeScript type checking

Git Hooks

This project uses Husky to manage Git hooks, which automate certain checks before commits and pushes. The hooks are located in the .husky/ directory.

Pre-commit Hook

Before a commit is finalized, the .husky/pre-commit hook runs:

1. Branch Check: Prevents committing directly to the main branch.
2. Type Generation: Runs npm run generate-types.
3. Type File Check: Ensures that any changes made to src/exports/roo-code.d.ts by the type generation are staged.
4. Linting: Runs lint-staged to lint and format staged files.

Pre-push Hook

Before changes are pushed to the remote repository, the .husky/pre-push hook runs:

1. Branch Check: Prevents pushing directly to the main branch.
2. Compilation: Runs npm run compile to ensure the project builds successfully.
3. Changeset Check: Checks if a changeset file exists in .changeset/ and reminds you to create one using npm run changeset if necessary.

These hooks help maintain code quality and consistency. If you encounter issues with commits or pushes, check the output from these hooks for error messages.

Troubleshooting

Common Issues

1. Extension not loading: Check the VSCode Developer Tools (Help > Toggle Developer Tools) for errors
2. Webview not updating: Try reloading the window (Developer: Reload Window)
3. Build errors: Make sure all dependencies are installed with npm run install:all

Debugging Tips

• Use console.log() statements in your code for debugging
• Check the Output panel in VSCode (View > Output) and select "Kilo Code" from the dropdown
• For webview issues, use the browser developer tools in the webview (right-click > "Inspect Element")