# 2.5.19. Custom Services

Custom services are stateful components of Buildbot that can be added to the `services` key of the Buildbot config dictionary. The following is the services that are meant to be used without advanced knowledge of Buildbot.

> - FailingBuildsetCanceller

> - OldBuildCanceller

More complex services are described in the developer section of the Buildbot manual. They are meant to be used by advanced users of Buildbot.