> For the complete documentation index, see [llms.txt](https://buildsystem.eintosti.de/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://buildsystem.eintosti.de/v4/reference.md).

# Reference

- [Config Reference](https://buildsystem.eintosti.de/v4/reference/config.md): Every key in config.yml, and what it changes.
- [Placeholders & Integrations](https://buildsystem.eintosti.de/v4/reference/integrations.md): Placeholders BuildSystem exposes, and the plugins it defers to.
- [Common Issues](https://buildsystem.eintosti.de/v4/reference/common-issues.md): Fixes for the problems people hit most often.
- [Changelog](https://buildsystem.eintosti.de/v4/reference/changelog.md): What changed in each release.