{
  "id": 13601005,
  "title": "Consistency is not a localized property",
  "url": "https://urgent.news/2026/10/11/consistency-is-not-a-localized-property",
  "topic": "tech",
  "section": "Tech",
  "published": "2026-10-11T00:51:28.000Z",
  "source": {
    "name": "Lobsters",
    "slug": "lobsters",
    "url": "https://n-the-loop.com/blog/consistency-is-not-a-localized-property/"
  },
  "original_language": "en",
  "account": "Consistency is a property that cannot be confined to a single component, as demonstrated by the experience with Apache Kafka. Achieving exactly-once processing in such a system required a significant effort from distributed systems engineers, including the development of new components and a complete rewrite of existing ones (Gustafson et al. 2016). Despite this effort, the creators of Kafka are clear about the limitations of their system: exactly-once processing is an end-to-end guarantee, and the application must be designed to avoid violating this property (Narkhede and Wang 2017).\n\nThe implications of this are twofold. First, someone must have a comprehensive understanding of the entire system to ensure consistency. Since no single component can guarantee this property, it falls to someone outside the components to maintain overall consistency. This person must take ownership of the global property and provide a guarantee that it remains intact (source 9e90b30e-f4a).\n\nSecond, the responsibility for maintaining global consistency is not something that can be delegated to machines alone. While components may claim that their part works correctly, this does not ensure that the system as a whole remains consistent. The lesson from this experience is that global, valuable properties should not be handed off to machines without a person who is accountable for the entire system and has the guarantee that it functions correctly (Olshan and Liu 2022). Even after eight years, Kafka's protocol had to be redesigned to address correctness issues that could potentially violate exactly-once processing (Olshan and Liu 2022).",
  "summary": null,
  "key_points": [
    "Consistency cannot be confined to a single component in Apache Kafka.",
    "Exactly-once processing requires end-to-end guarantee, application design.",
    "Global consistency needs human accountability, not just machine reliability."
  ],
  "editors_take": "Maintaining system consistency requires a person with comprehensive understanding to take ownership of the global property, ensuring it remains intact, as no single component can guarantee this property on its own.",
  "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."
}