2025-09-2212 min readAllow us to introduce Cap'n Web, an RPC protocol and implementation in pure TypeScript.Cap'n Web is a spiritual sibling to Cap'n Proto, an RPC protocol I (Kenton) created a decade ago, but designed to play nice in the web stack. That means:Like Cap'n Proto, it is an object-capability protocol. ("Cap'n" is short for "capabilities and".) We'll get into this more below, but it's incredibly powerful.Unlike Cap'n Proto, Cap'n Web has no schemas. In fact, it has almost no boilerpl...