"Treat market validation as your first unit test" is the line that should be pinned in every indie hacker community. The engineer's instinct to build first is exactly what killed my first two side projects — both technically solid, both solving problems nobody was searching for. The programmatic niche discovery angle is the practical version of "talk to users": instead of guessing, you measure whether anyone is even asking the question. My own rule now is embarrassingly simple — if I can't find ten people already complaining about the problem in public, I don't write a line of code.