> How does a “small startup” end up with a multi million line “legacy” codebase?

Easy! The output of 6 months ago Opus! Which seemed so wonderful at the time.

This! I don't think folks understand how easy it is to go from greenfield to brownfield with these tools, esp if your organization is only valuing velocity. Meaning your doing full agentic development on large features, barely reviewing any code, and shipping without much refinement. It's insane, but this appears to be the status quo in SF startups.