# Development

## Clangd

To get language support in VSCode and other IDEs we recommend using `clangd`-based language server.
The server reads supplied `compile_flags.txt` file for correct options and include paths to resolve symbols
in opened files.

To support `clangd` project-level operations like `Find References` `compile_commands.json` file needs to
be generated that will list all files in the project. If you do this, then it needs to be re-generated periodically
when new files appear.

1.  Install `gen-compile-commands`

```sh
just prepare
```

2.  Generate `compile_commands.json`

```sh
just compile-commands
```

## Dependencies

In order to install dependencies, please run the following command. Also refer to Building workerd in README.md for the list of required dependencies by platform.

- For Ubuntu:

```sh
just prepare-ubuntu
```

## Code Formatting

workerd code is automatically formatted by clang-format. Run `python ./tools/cross/format.py` to reformat the code
or use the appropriate IDE extension.
While building workerd currently requires LLVM 19 or above, formatting requires clang-format 18.1.8 as different
versions result in different format suggestions. This is automatically fetched using Bazel and does not need to be
installed manually.

Code formatting is checked before check-in and during `Linting` CI build.