The software post-mortem is well known. It’s a standard best practice that really marks the end of any software project. It also fits in well with the Agile manifesto, specifically the retrospective - always be reflecting, always be improving.
Code reviews are amazing for many reasons. And everyone on the team should contribute. Interestingly, the behavior of an engineer with respect to code reviews changes based on seniority or tenure within a team or code repository. I like to refer these changes as “phases”.