How developers can build a Nostr app without asking permission.

There's no company to call, no API key to apply for, no terms of service review. The Nostr protocol is a public spec (just read the NIPs). You connect to relays over standard WebSockets. You sign events with open cryptographic standards (secp256k1). Everything is documented and open-source. You pick it up, implement it, and deploy that's it. This is the same reason anyone could build an email client in 1995 without asking Microsoft. Open protocols are inherently permissionless by design.