Petari is an ongoing fan decompilation project targeting Nintendo's Super Mario Galaxy on the Wii, hosted by the SMGCommunity organisation on GitHub. The project aims to produce a matching, human-readable reconstruction of the original game's source code.
A new commit (55803a0) has landed in the repository, continuing incremental progress on the decomp effort. Followers of the project can track development directly on the SMGCommunity GitHub page.