📝Lightweight RFC-like process
Do planning before building something. In-person white-boarding or just talking things through with the team. Anything as long as you’re clear on how the thing is going to be built.
Capture this plan in a short written document (RFC). Once you agree, it should be quick and easy to write.
Have a few selected people approve the plan before starting work.
Send this planning document to all engineers in the company. (My company is too big for this to work, but circulating documents inside the unit should be fine.)
Have everyone follow the above steps.
See also
Architecture Decision Record—as an example format
Sign-offs encourage Big Design Up Front—does requiring people approve the plan encourage big-design-up-front?