{
  "added_at": "2026-11-09",
  "additional_evidence_urls": [
    "https://github.com/ForNeVeR/O21/blob/cad90840ce330e4c676e644c171d462d0f3784a5/CHANGELOG.md"
  ],
  "category": "reconstruction-cases",
  "class": "game",
  "description_en": "O21 rebuilds the 1995 Windows game U95 as an F# open-source remake. Its author describes a black-box process based on observing the running game and reading its data files; the current engine includes rendering, menus, bonuses and some enemy behaviour but is not yet playable.",
  "description_zh": "O21 以 F# 重建 1995 年的 Windows 游戏《U95》。作者说明其黑盒方法是观察原游戏运行并阅读数据文件；现有引擎已实现渲染、菜单、奖励及部分敌人行为，但目前尚不可玩。",
  "entry_url": "https://awesomerea.org/resources/o21-u95-case/",
  "entry_url_zh": "https://awesomerea.org/zh/resources/o21-u95-case/",
  "evidence_class": 2,
  "evidence_status": "observed",
  "evidence_url": "https://github.com/ForNeVeR/O21/blob/cad90840ce330e4c676e644c171d462d0f3784a5/README.md",
  "group": "cases",
  "id": "o21-u95-case",
  "json_url": "https://awesomerea.org/resources/o21-u95-case/record.json",
  "kind": "case-study",
  "markdown_url": "https://awesomerea.org/resources/o21-u95-case/index.md",
  "markdown_url_zh": "https://awesomerea.org/zh/resources/o21-u95-case/index.md",
  "name": "O21: a black-box remake of U95",
  "name_zh": "O21：基于黑盒观察重建《U95》",
  "reconstruction_method": "other",
  "record_type": "resource",
  "relationship": "independent-reconstruction",
  "requirement_facets": [
    "prerequisites",
    "prerequisites",
    "limits",
    "license"
  ],
  "requirements": [
    "Original U95 resources are needed to run the game.",
    "Development builds require .NET 10 SDK or later.",
    "The current implementation is not in a playable state.",
    "MIT license, except where individual files state otherwise."
  ],
  "requirements_zh": [
    "运行游戏需要原版《U95》的资源。",
    "开发版构建需要 .NET 10 SDK 或更新版本。",
    "当前实现尚不可玩。",
    "采用 MIT 许可证，个别文件另有注明的除外。"
  ],
  "scope": "unknown",
  "targets": [
    "game"
  ],
  "url": "https://github.com/ForNeVeR/O21",
  "verification": "source-reviewed",
  "verified_at": "2026-11-06"
}