CapTP

• #decentralization
• #indieweb
• #programming
• #technology

Capability Transport Protocol

CapTP is a protocol to allow "distributed object programming over mutually suspicious networks, meant to be combined with an object capability (ocap) style of programming".

A way to use the actor model/message passing to build secure distributed systems where permissions to do certain actions is a first-class concept.

The basic idea is that messages are passed between actors, typically via RPC. When an actor passes credentials to its parent, the return value is a proxy object, held in memory by the parent, whose exposed methods are determined by the actor's credentials. Since the actor has no direct access to the object, it cannot perform any action except what has been permitted by the parent.

The concept is well explained in the blog post by Cloudflare announcing Cap'n Web.