{
  "id": 1371449,
  "title": "Unhandled Events, Not Broken States, Are What Kill Your State Machine",
  "url": "https://urgent.news/2026/08/16/unhandled-events-not-broken-states-are-what-kill-your-state-machine",
  "topic": "tech",
  "section": "Tech",
  "published": "2026-08-16T22:39:50.000Z",
  "source": {
    "name": "Dev.to",
    "slug": "dev-to",
    "url": "https://dev.to/codepy_1473/unhandled-events-not-broken-states-are-what-kill-your-state-machine-4dl6"
  },
  "original_language": "en",
  "account": null,
  "summary": "The article emphasizes that the real issues in state machines often stem from unhandled events rather than broken states. While it may seem intuitive to test the legal paths of a state machine, such as an order moving from pending to paid, the failures that typically freeze a service occur in the cells that are never filled in. A missing transition is worse than a wrong transition, as the latter at least throws an exception that can be logged, while the undefined one often falls through to a default branch that silently returns the current state and reports success. This issue becomes more pronounced when the state machine is drafted by a model, which may not account for edge cases like a cancel event after an order has already shipped. The article suggests starting from the contract rather than a vague request to attack the machine, focusing on ensuring every combination of state and event has an explicit owner, even if the owner is a rejection. This clarity can be achieved by using cheap compute for enumeration and a free model to suggest which cells should refuse the event instead of handling it.",
  "key_points": [],
  "editors_take": null,
  "illustration": null,
  "coverage": {
    "outlets": 1,
    "also_reported_by": []
  },
  "ai_generated": true,
  "disclaimer": "Summaries, key points and the editor’s take are written by software from other outlets’ reporting and may contain errors — always check the linked original."
}