# CELUM Connectors

Here you'll find the configurable properties of our reusable [CELUM Connectors](https://www.brix.ch/extensions/celum-extensions). In contrast to the [extensions](/celum_extensions) that run inside CELUM, connectors run in some 3rd-party system and connect to CELUM from the outside via an API. So the two systems must be able to communicate between one another in order for this to work.

> > > > 6.20 (aka 25.1) contains a lot of breaking changes due to dependency updates, so for the first time in a long time you probably won't be able to simply deploy extensions designed for previous versions. When in doubt, [ask us](https://support.brix.ch)!