This open source repository contains the standard CodeQL libraries and queries that power GitHub Advanced Security and the other application security products that GitHub makes available to its customers worldwide.

There is extensive documentation on getting started with writing CodeQL using the CodeQL extension for Visual Studio Code and the CodeQL CLI.

We welcome contributions to our standard library and standard checks. Do you have an idea for a new check, or how to improve an existing query? Then please go ahead and open a pull request! Before you do, though, please take the time to read our contributing guidelines. You can also consult our style guides to learn how to format your code for consistency and clarity, how to write query metadata, and how to write query help documentation for your query.

For information on contributing to CodeQL documentation, see the "contributing guide" for docs.

The code in this repository is licensed under the MIT License by GitHub.

The CodeQL CLI (including the CodeQL engine) is hosted in a different repository and is licensed separately. If you'd like to use the CodeQL CLI to analyze closed-source code, you will need a separate commercial license; please contact us for further help.

If you use Visual Studio Code to work in this repository, there are a few integration features to make development easier.

You can install the CodeQL for Visual Studio Code extension to get syntax highlighting, IntelliSense, and code navigation for the QL language, as well as unit test support for testing CodeQL libraries and queries.

The .vscode/tasks.json file defines custom tasks specific to working in this repository. To invoke one of these tasks, select the Terminal | Run Task... menu option, and then select the desired task from the dropdown. You can also invoke the Tasks: Run Task command from the command palette.