This open source repository contains the standard CodeQL libraries and queries that power [GitHub Advanced Security](https://github.com/features/security/code) and the other application security products that [GitHub](https://github.com/features/security/) makes available to its customers worldwide.
There is extensive documentation about the [CodeQL language](https://codeql.github.com/docs/), writing CodeQL using the [CodeQL extension for Visual Studio Code](https://docs.github.com/en/code-security/codeql-for-vs-code/) and using the [CodeQL CLI](https://docs.github.com/en/code-security/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](CONTRIBUTING.md). You can also consult our [style guides](https://github.com/github/codeql/tree/main/docs) 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.
The CodeQL CLI (including the CodeQL engine) is hosted in a [different repository](https://github.com/github/codeql-cli-binaries) and is [licensed separately](https://github.com/github/codeql-cli-binaries/blob/main/LICENSE.md). If you'd like to use the CodeQL CLI to analyze closed-source code, you will need a separate commercial license; please [contact us](https://github.com/enterprise/contact) for further help.
If you use Visual Studio Code to work in this repository, there are a few integration features to make development easier.
### CodeQL for Visual Studio Code
You can install the [CodeQL for Visual Studio Code](https://marketplace.visualstudio.com/items?itemName=GitHub.vscode-codeql) 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.
### Tasks
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.