Staff Engineers Prefer 'What to Refuse to Build' Over Traditional Build vs Buy

A staff engineer argues that the common 'build vs buy' framework is insufficient for system design decisions. The key questions should focus on whether a component is undifferentiated heavy lifting or contributes to product differentiation. They emphasize that building commodity features like authentication or billing creates long-term maintenance debt that vendors absorb. Therefore, engineers should primarily build what changes when their product succeeds and outsource standardized functions.