Periscope module has dependency to UI module - https://git.magnolia-cms.com/projects/MODULES/repos/periscope/browse/periscope-core/pom.xml#37

Ui module has dependency to periscope - https://git.magnolia-cms.com/projects/PLATFORM/repos/ui/browse/magnolia-admincentral/pom.xml?at=refs%2Fheads%2Ffeature%2Fresurface#53

With circular dependency we are not able to release the modules. If you start with release of periscope than it will fail because UI is on SNAPSHOT, which you can't release because there's SNAPSHOT of periscope.

Only one module should have dependency to the other. Periscope should be just backgroud for search itself, so it should not have dependency to UI. All the UI actions should be part of findbar(UI).