APIs are the connective tissue of modern software. When they're well-designed, teams move fast, integrations are painless, and the system scales naturally. When they're not, every new feature requires a meeting, every integration is a custom project, and the system becomes a web of workarounds.
The best APIs we've seen share a few traits: consistent naming, predictable behavior, clear error messages, and versioning from day one. They're designed for the developers who will consume them, not the developers who build them. That shift in perspective makes all the difference.
Versioning is not optional
Every API will change. The question is whether those changes break existing consumers. Versioning lets you evolve the API without forcing everyone to upgrade simultaneously. It's more work upfront, but it's the difference between a platform that grows and one that stagnates because nobody wants to risk updating.
