Analyzing Python asyncio Primitive Limitations for Shared State Coordination

Coordinating concurrent tasks around shared state is one of the most common problems in Python's asyncio.

The standard library gives you asyncio.Event and asyncio.Condition, but each has a gap that only shows up under real concurrency pressure.

We hit this while building Inngest's Python SDK, where multiple async handlers coordinate around WebSocket connection state.

This post works through each primitive, shows exactly where it breaks, and iterates toward a solution that handles every case we threw at it.

We tried Event, Condition, and Queue. Each one gets closer but still breaks under real concurrency. Here's the observable pattern that finally works.