Programs run as generators that yield what they wait for (threads.ts); the engine resumes them after every event. TCP connect, send, receive, accept and name resolution exist as such steps; the blocking calls wrap them. EchoRun records eight stories in Java FILIUS, frames, tables and each program's window lines; echoJava.test.ts plays them card by card. Not taken from Java: a connection without a route hangs for ever; a server switched off leaves its connections' last FIN unanswered. Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>