# Check Config It can be cumbersome when you have multiple projects and environments with configuration files which need to be upgraded and keep in sync regularly. Check-config will help you with i.e. making sure that the configuration file have the (upgraded) settings. Check-config works with checker files in which you define checks, ie ```checkers.toml # check that .venv is included in the .gitignore [".gitignore".lines_present] __lines__ = ".venv" ``` With `check-config` you can check (for example in a build pipeline) whether your files passed the checks. Most checks can also be automatically fixed with `check-config --fix`, so in this case a missing line will be added to the `.gitignore`. A large number of [file types](features/#file-types) and [checks](checkers) are supported or will be supported in the near [future](features).