ACL 151. Fifth in its series, the Annie Cameron Library Catalog 5 archives entries into the ACL between 2019 May 20 and 2021 February 23. This ACL AssetCacheLocatorSource, Call HistorySyncHelper, Observability Space, Observability Stack, and TimeSynchUtility provides big picture cohesion, direction, purpose, and visibility to the flip books of the entry period. Entry pace in the Catalog 5 is driven by completing the compilation task before 2021 February 18 when NASA Perseverance was scheduled to touch down in Jezero crater carrying on board 39 data packages from the nz MI.