{
  /* The TypeScript configuration, and now the only one.
     It began as a translation of `jsconfig.json` so that the first day of the
     migration checked exactly what the last day before it checked. That file
     has been deleted: it was inert from the moment this one appeared, because
     TypeScript ignores a jsconfig wherever a tsconfig sits beside it, and
     keeping a second stale copy of the options invited someone to edit the one
     nothing reads. */
  "compilerOptions": {
    "baseUrl": ".",
    "paths": {
      "@/*": ["./src/*"]
    },
    "jsx": "react-jsx",
    "module": "esnext",
    "moduleResolution": "bundler",
    "lib": ["esnext", "dom", "dom.iterable"],
    "target": "esnext",

    /* Vite builds; this config only ever checks. Stating it means no stray
       output can appear next to a source file if anyone runs `tsc` directly. */
    "noEmit": true,

    /* `allowJs` and `checkJs` were here for the migration and are gone: `src`
       holds 321 TypeScript files and no JavaScript, and nothing under `src`
       imports a `.js` module, so neither option has anything left to act on.
       They are removed together because they are coupled — `checkJs` without
       `allowJs` is TS5052, a configuration error rather than a code one.

       Removing them also closes a door. With `allowJs` on, a `.js` file added
       under `src` would be compiled and bundled silently; now it is a
       resolution failure, which is the correct outcome for a codebase that has
       finished migrating. */

    /* NEW. esbuild compiles each file on its own and cannot see across them, so
       a construct that needs whole-program knowledge — re-exporting a type as
       if it were a value, most often — works under `tsc` and breaks in the
       bundle. This makes tsc refuse what esbuild could not have done anyway. */
    "isolatedModules": true,

    /* NEW. macOS does not distinguish `Button` from `button`; CI does. Without
       this, a mis-cased import is a green local build and a red pipeline. */
    "forceConsistentCasingInFileNames": true,

    "skipLibCheck": true,
    "allowSyntheticDefaultImports": true,
    "esModuleInterop": true,
    "resolveJsonModule": true,

    /* CHANGED, from `[]`. The empty list suppressed every ambient type package,
       which is why `import.meta.env` and `import.meta.glob` — Vite build-time
       APIs, absent from the standard `ImportMeta` — were reported as errors in
       eight places across the app.

       Named explicitly rather than left to default, because the default pulls
       in EVERYTHING under node_modules/@types, and `@types/node` is installed.
       In browser code that would make `setTimeout` return a `NodeJS.Timeout`
       instead of a number, which is wrong and quietly infectious: three
       components store a timer handle in a `useRef` and would be typed against
       a runtime they do not run on. Node's types belong to `vite.config.js` and
       `scripts/`, neither of which this project includes. */
    "types": ["vite/client"],

    /* Off for now, and turned on a flag at a time later in the migration —
       `noImplicitAny`, then `strictNullChecks`, then the rest. Enabling it here
       would bury the ~70 real errors this project already has under several
       hundred more, and the point of going file by file is that each step is
       small enough to read. */
    "strict": false
  },

  "include": ["src/**/*"],

  /* `src/components/ui`, `src/api` and `src/lib` used to be listed here,
     inherited from jsconfig, each meant to come off as its tree was converted. They
     were missed, and the miss was quiet by construction: excluding a file only
     keeps it out of the ROOT set, and anything an included file imports is
     pulled in anyway, so 318 of the 321 files were being checked regardless.

     The three that were not are the ones nothing under `src` imports —
     `api/seed.ts`, `api/attendanceSeed.ts` and `lib/skills/positionFlow.ts`.
     They are not dead: `scripts/` loads them, `seed.ts` from six places. They
     were simply invisible to `tsc`, and held four real errors.

     Removed before the strictness ratchet rather than after, because a flag
     measured against an incomplete root set gives a number that grows again
     later for reasons that have nothing to do with the flag. */
  "exclude": ["node_modules", "dist"]
}