{
  "id": 6298577,
  "title": "Zero Dependencies, 456 Tests, and One Bug All of Them Missed",
  "url": "https://urgent.news/2026/09/08/zero-dependencies-456-tests-and-one-bug-all-of-them-missed",
  "topic": "tech",
  "section": "Tech",
  "published": "2026-09-08T16:43:22.000Z",
  "source": {
    "name": "Dev.to",
    "slug": "dev-to",
    "url": "https://dev.to/abhishek_jha_4287a6f8711f/zero-dependencies-456-tests-and-one-bug-all-of-them-missed-13jn"
  },
  "original_language": "en",
  "account": "The test suite for a photo timeline app, named Darkroom, was functioning perfectly. The app allows users to view their photos on a Wi-Fi network, sorted by the date they were taken. Darkroom was unique in that it had no dependencies listed in its Cargo.toml file, meaning all its functionality was custom-built. Despite this, the app had 456 automated tests that all passed, demonstrating the robustness of the code. However, the app was missing one crucial feature - the ability to generate QR codes. This oversight led to a bug that went unnoticed by the extensive test suite. The bug was discovered when external QR code decoders were used to scan the generated codes, revealing a single bit of incorrect ordering. This seemingly small mistake had a significant impact on the functionality of the app.",
  "summary": "The test suite was green. All of it. Every assertion about the QR encoder I'd written passed, the way it had passed for weeks. I held my phone up to the screen anyway, more out of habit than suspicion, and the camera just sat there. No beep, no flash, no redirect. Nothing. A perfectly scannable-looking grid of black and white squares that no scanner on Earth could actually read. That…",
  "key_points": [
    "Darkroom app has zero dependencies",
    "456 automated tests passed successfully",
    "QR code generation feature missed, causing bug"
  ],
  "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."
}