August 1, 2026 · Joy
Why JoyMux exists
People run more AI coding agents across more harnesses. Execution still lives in disposable terminals.
A crash wipes progress. Output scrolls away. Context gets duplicated. RAM spikes. Then they pay tokens again for the same work.
Most tools focus on the agent. Almost nobody focuses on execution state underneath — what survives when the terminal dies.
The scene that started it
I was running many coding agents every day — Codex, Claude Code, Gemini, others. Terminals died. Context got copied into the next prompt. Crashes forced full re-runs and a second token bill. The Mac struggled. The deeper pain was lost execution state.
Buying another machine would have papered over it.
What I actually built
JoyMux is a local persistent execution layer shared across coding agents. Crash? Resume. Missed output? Replay it. Too much context? Send the delta, not the whole terminal history.
Your agent can change. Your execution state stays.
The machine staying calmer is a side effect of fewer duplicated contexts and pile-ups — not the headline.