{
  "id": "legacy-code.unmeasured",
  "term": "legacy code",
  "sense": "unmeasured",
  "pos": "noun",
  "status": "review",
  "level": 15,
  "arena": "software development",
  "domain": "computer science",
  "style": "window",
  "definition": "a system whose parameter window no living maintainer has measured, still inside it, maintained without knowing where its walls are.",
  "folk_gloss": null,
  "emergence": {
    "components": [
      "window.range",
      "wall.range-end",
      "parameter.condition",
      "maintenance.upkeep",
      "drift.aimless",
      "model.representation",
      "self-model.reflexive",
      "inside.spatial",
      "know.cognitive",
      "live.biological",
      "measure.quantitative",
      "measurement.quantitative",
      "still.quiet",
      "system.organized"
    ],
    "interaction": "The interaction of maintenance, unmeasured boundaries, and the absence of a cognitive model of those boundaries allows the persistence of a system in ignorance of its own limits.",
    "novel_properties": [
      "unmeasured persistence",
      "maintained ignorance",
      "precarious stability"
    ]
  },
  "examples": [
    {
      "text": "The Therac-25 radiation therapy machine malfunctioned in 1985 due to unmeasured race conditions in code originally written in the 1970s.",
      "domain": "computing"
    },
    {
      "text": "The New York City subway's signal system, largely unchanged since the 1940s, runs trains with timetables adjusted by hand-drawn chalk logs.",
      "domain": "engineering"
    },
    {
      "text": "Farmers in the Sahel maintain irrigation ditches laid during French colonial rule, though no one recalls the original grading specifications.",
      "domain": "institutions"
    }
  ],
  "relations": [],
  "used_by": [],
  "forms": [],
  "closed": false,
  "provenance": {
    "author": "retrofit:qwen/qwen3-235b-a22b-2507",
    "date": "2026-07-29",
    "confidence": 0.8,
    "sources": [
      "Sample/nothing-was-removed.md"
    ],
    "reconciled": {
      "by": "openrouter:qwen/qwen3-235b-a22b-2507",
      "date": "2026-07-31",
      "changed": "definition",
      "note": "Definition updated to clarify intent and better reflect constituent components; omitted 'windows.opening' as irrelevant (spatial metaphor not literal). All semantic gaps addressed by adding missing co"
    },
    "restored": {
      "date": "2026-07-31",
      "from": "Sample/nothing-was-removed.md",
      "replaced": "A system whose parameter window no living maintainer has measured, still maintained without knowing where its boundaries end."
    }
  },
  "canonical": "https://emergencemachine.com/tools/lexicon/what-is-the-meaning-of-legacy-code.unmeasured"
}