A settings-file tool from 2009 is being retired. Write the parser that replaces it, and make it agree with the tool on every file.
A service left behind one recorded run of its activity and no documentation of how it works. Study it, then build a model that predicts where the activity is heading and picks out the records that don't belong.
A binary-message decoder that shields an internal system is being replaced, but the old one survives only as a service you can query, not read. By probing it within a limited budget, make your replacement handle every message exactly as it does, especially the malformed and malicious ones it was hardened against.
