Over a MessagePort

servePort(handlers, port) from foldkit-remote-server/port answers foldkit-remote/port's client over one MessagePort, for a server in a worker or in the page. It speaks Effect's RPC worker protocol, so reads, queries, mutations and live streams cross it with their typed errors, and an interrupted call interrupts its handler. It returns once the client closes its end; interrupt it to stop sooner:

import { servePort } from 'foldkit-remote-server/port'

// In the host, for each port a page hands it; `handlers` as above.
Effect.runFork(servePort(handlers, port))

It binds no principal: pass the handlers for the conversation's own, as everywhere else. It needs no browser package: the port is driven through effect/workers directly.