Apr 23, 2026 — 11 min — Systems Notes
State Machines in Python: from xstate-python to LangGraph
Why an agent harness re-fired a half-finished tool after a worker restart, the four Python libraries that solve different parts of the problem, and a concrete contribution roadmap for xstate-python.
Outcome: Reader can map a Python workflow to the right state-machine library, distinguish statechart formalism from durable execution, and know where to start contributing to xstate-python with file paths and named missing features.