Frankly I feel like most engineering on existing systems is more psychology than coding. "What was this author probably thinking when they wrote this?" "Where would the last person in this codebase probably have hacked in this feature?" "What did they think I would think this interface name means?" The ability to guess intent from archeological evidence is a key skill.
@jjwolverine “omg what the fuck were they thinking when they did this... idiots...”
@jjwolverine I think about Vinge's "Code Archaeologists" from FutD pretty often