Zawinski's Law

Zawinski's law (Jamie Zawinski, Netscape/Mozilla): "Every program attempts to expand until it can read mail. Those programs which cannot so expand are replaced by ones that can." The joke is that successful software accretes features—email, chat, calendaring—until it becomes a platform. The serious point: feature creep and scope expansion are the default; programs that stay focused are the exception and often get displaced by ones that do more. It's a warning: without discipline, "one more feature" wins and complexity compounds. Building & scaling: the pull toward becoming everything is strong; resisting it is a design choice.

Treat scope expansion as the default. Actively resist: define the minimal job, say no to "and also," and split into smaller programs or services when one tool is doing too much. Prefer composition (small tools that work together) over one mega-app. In product: guardrails (roadmap discipline, "one thing" positioning) counter the law.

Zawinski's law: programs tend to expand in scope until they do everything (including "read mail"); focused programs get replaced by expanders. Treat expansion as the default; resist with focus, modularity, and composition.