krow_talent_app/MIGRATION_BASELINE.md

# TypeScript migration — baseline

The state of this repository **immediately before** the first source file was
renamed, measured rather than assumed. Everything the migration does is checked
against these numbers; a figure that moves without a phase claiming it is a
regression.

Measured on 2026-09-11, on `main` with a clean tree, before any change in
Milestone 1.

## The numbers

| Check | Command | Baseline |
|---|---|---|
| Types | `npm run typecheck` | **FAILS — 71 errors across 27 files** |
| Lint | `npm run lint` | **PASSES**, exit 0 |
| Lint (with warnings) | `npx eslint .` | 289 problems — 0 errors, 289 warnings |
| Files linted | `npx eslint . --format json` | 302 |
| Behaviour | `npm test` | **1641 / 1642 checks passed** |
| Build | `npm run build` | succeeds |
| Owliver, via the suite | `npm test` section 21 | **all green** — schema, skills, routes, and per-context skills, suggestions, prompts and intent routing |
| Owliver, standalone | `node scripts/owliver-baseline.mjs` | **FAILS — pre-existing, see below** |

### The 71 type errors, by code

| Code | Count | What it is |
|---|---|---|
| TS2339 | 38 | Property does not exist on an inferred type |
| TS2741 | 9 | Missing required prop in JSX |
| TS2353 | 9 | Unknown property in an object literal |
| TS2345 | 6 | Argument type mismatch |
| TS2554 | 2 | Wrong argument count |
| TS2362 / TS2363 | 4 | Arithmetic on a non-number |
| TS2739 / TS2559 / TS2349 | 3 | Missing props / no common props / not callable |

These are **pre-existing**. They were not introduced by the migration and the
migration is not obliged to fix them; they are the backlog it has to avoid
adding to. Six of them are `import.meta` errors that Phase 1 resolves as a side
effect of configuring `vite/client`.

Note that `npm run typecheck` **is not run by CI** (`.github/workflows/ci.yml`
runs lint, test, build and the seed check). That is how 71 errors accumulated
without anyone seeing them. Wiring it in is the last phase of the migration, not
the first — it cannot be a gate until it is green.

## The standalone Owliver script is already broken

`node scripts/owliver-baseline.mjs` fails before any of this began — verified by
stashing every change and running it on a clean `main`, where it fails
identically. It is **not** caused by the migration.

```
Failed to scan for dependencies from entries:
  index.html
  scripts/__baseline__/activity-page.pre-migration.html
  … the other seven snapshots …
  ✘ [ERROR] The server is being restarted or closed. Request is outdated [plugin vite:dep-scan]
Owliver behaviour has DRIFTED from the baseline.
```

Two things are going on, and neither is a real drift. Vite's dependency scanner
treats every `*.html` under the project root as an entry point, so the eight
captured SSR snapshots in `scripts/__baseline__/` are scanned as if they were
pages of the app. The script then calls `server.close()` as soon as
`captureBaseline` returns, while that scan is still running, and the scan
reports that it was cancelled. The capture comes back incomplete and the
comparison calls it drift.

**The coverage itself is not lost.** `skill-check.mjs` imports the same
`captureBaseline` and the same `BASELINE_PATH` and asserts against them in
section 21, and it does enough other work afterwards that the scan finishes. Run
`npm test` and the whole section is green:

```
── Owliver behaviour baseline ──
[  ok  ] baseline schema matches — expected 1, got 1
[  ok  ] every skill that existed before the agent layer still registers — 23 kept, 1 added since
[  ok  ] every route that resolved before resolves the same way — 18 unchanged
[  ok  ] controlCenter: keeps every skill it had — 7 skill(s), unchanged
…per context: page key, skills, suggestions, prompts, intent routing
```

So **`npm test` is the Owliver drift check for the duration of the migration**,
and the standalone script is a convenience wrapper that needs repairing on its
own terms — excluding `scripts/__baseline__` from the scan, or awaiting the
optimizer before closing. That repair is not part of the migration: it changes
a script's behaviour, and this milestone's whole claim is that it changed none.

## The one failing check

```
1641/1642 checks passed

Failed:
  - the backend fixture is in step with this seed (stale — run `npm run seed:fixture`)
```

`scripts/__baseline__` is intact and `owliver-baseline.mjs` matches; this is not
an Owliver failure. `seed/fixtures/seed.json` in the sibling `krow-backend`
checkout has drifted from `src/api/seed.js`.

**This failure predates the migration and is unrelated to it. It is recorded
here so that it is never mistaken for something the migration caused, and it is
deliberately left alone** — regenerating the fixture would write into another
repository and change what the backend seeds, which is a product change wearing
a migration's clothes. Fix it separately, on its own terms.

## What "unchanged" means for the Owliver / agent flow

The agent flow is ~112 files and 38% of the codebase, and it is converted last,
by rename and type annotation only. The evidence that it still behaves
identically is already in the repository and needs nothing new:

- `npm test` — 1642 checks covering skill discovery, routing, context
  resolution and SSR-rendered markup.
- `scripts/__baseline__/owliver-baseline.json` — contexts, skill ids and routes.
- `scripts/__baseline__/*.pre-migration.html` — eight pages of byte-level SSR
  output.
- `node scripts/owliver-baseline.mjs` — the drift check.
- CI's `FLOOR = 900` — fails if the suite silently shrinks.

**These artifacts are read-only for the duration of the migration.** If the
baseline drifts, revert the change. Regenerating it to clear a red check records
the regression instead of catching it, which is worse than having no baseline —
`owliver-baseline.mjs` says as much in its own header.

`src/agents/**/*.md` and `src/skills/**/*.md` are likewise untouched throughout:
they are the definitions the flow is built from, not code being migrated.

## How to re-measure

```bash
npm run typecheck; echo "exit=$?"
npm run typecheck 2>&1 | grep -c "error TS"
npm run lint; echo "exit=$?"
npx eslint . --format json | python3 -c "import json,sys;print(len(json.load(sys.stdin)))"
npm test
node scripts/owliver-baseline.mjs
npm run build
git diff --stat -M
```

---

## 2026-09-20 — closing addendum: the migration is complete

Everything above this line is the record as measured on 2026-09-11 and is left
exactly as it was written. The numbers in it describe `main` before the first
rename; they are the thing the migration was checked against, so correcting them
to today's figures would destroy the comparison rather than update it. What
follows is the other end of that comparison.

### Final state, measured on the `ts-migration` branch

| Check | Command | 2026-09-11 baseline | Now |
|---|---|---|---|
| Types | `npm run typecheck` | FAILS — 71 errors / 27 files | **0 errors**, 321 files in the program |
| Lint | `npm run lint` | PASSES, exit 0 | PASSES, exit 0 |
| Lint (with warnings) | `npx eslint .` | 0 errors, 289 warnings | 0 errors, 289 warnings |
| Behaviour | `npm test` | 1641 / 1642 | **1693 / 1693** |
| Build | `npm run build` | succeeds | succeeds |
| Bundle | `dist/assets/index-*.js` | — | `74d17e2d5cafdd6f88eaf6d89ffdab11` |
| Owliver, standalone | `node scripts/owliver-baseline.mjs` | FAILS — pre-existing | **matches the baseline** |
| Backend fixture | `npm run seed:check` | FAILS — stale | **in step** |

No `.js` or `.jsx` remains under `src/`: 103 `.ts`, 216 `.tsx` and 2 `.d.ts`.
`src/agents/**/*.md` and `src/skills/**/*.md` are untouched, as promised.

### The three items this document left open, and where they were closed

**The standalone Owliver script.** Recorded above as failing before any of this
began, verified by running it on a clean `main`. The byte-exact comparison was
reporting one real difference: the baseline held 23 skills and the runtime
resolved 24, because `create-employee-role` was added after the baseline was
last written and nobody recaptured it. `npm test` tolerated it — its check
asserts only that nothing was *removed*, and read "23 kept, 1 added since" — so
the drift was visible only to the stricter script. Refreshed in `34505d7`:
three inserted lines, no deletions, routes byte-identical at 18 and all eleven
contexts unchanged. The check now reads "24 kept, 0 added since".

**The backend seed fixture.** Recorded above as predating the migration and
deliberately left alone. It stayed that way for good reason: the generator was a
version behind the seeder and emitted no `users` key, so regenerating would have
dropped `employer@krow.app` from every fresh seed and left nobody to sign in as
to reach the employer console. Fixed in `3ddacf2` by teaching the generator to
emit the key, not by overwriting the fixture — with that change the generator
reproduces the committed fixture byte for byte, so `seed.json` in the sibling
repository was never written to at all.

**The HTML render baselines.** Recorded above as read-only for the duration of
the migration, and that held: they were untouched through every phase. Three of
them — Hired History, Analytics and Candidates — were recaptured in `878a235`,
after the migration, because a parallel feature removed demo data those files had
captured while it was still in effect. They are renamed `*.render.html`, since a
file called `pre-migration` holding post-feature markup is a lie in the filename.
The other five still hold genuine pre-migration markup, still pass, and keep the
name. One check that could no longer be satisfied was replaced by three that read
the render directly; `scripts/__baseline__/README.md` has the detail.

### Commits

    3ddacf2  fix(seed): emit the users array the backend seeder reads
    878a235  test(baseline): recapture the three HTML baselines that held invented people
    34505d7  chore: refresh owliver baseline

Strictness remains as debt rather than a blocker: `strict: true` reports 4438
errors, `noImplicitAny` 3317 and `strictNullChecks` 1794, while the committed
configuration reports none. None of it affects emitted output — the production
bundle hash is unchanged — so it is hardening work, not migration work.