docs: the landing page says what this is before it draws how it works

[lex00]

Not filed against an issue — this came out of watching the vocabulary get hammered out against a skeptic in real time. #181's third move is adjacent but this is a different and I think better change than the reordering it proposed.

The inversion

The page order was hero → loop diagram → code comparison → platforms → proof. A cold reader met a six-node mechanism diagram before anything gave them words for it.

And the plain statement already existed — buried as the third sentence under the code:

The second one has completion and a type error on a misspelt key. It reuses one helper across repositories. The tool reads the same object from either file and never executes the second one to get it.

Phrased as a property of the tool rather than as what the thing is.

Now

Introduction between the hero and the loop, with .Content moved up to join it. Order is what it is → an example → how it moves, so the diagram illustrates something the reader already has words for.

Your configuration is a TypeScript file. A separate program reads it and works out the values itself, refusing anything it would have to run.

Not the type system, so no tsc and no types involved. Not a sandbox either. Think a JSON parser that also understands 1 + 1, spread, and references into other files.

A call to Date.now() is refused rather than executed, and that file falls back to being run normally. You are told which files those were. What comes back is reproducible from the source alone, which is the thing running it can never give you.

Three paragraphs, three jobs: what it is, which frames it is not, why that matters.

Two choices worth defending

Naming the wrong frames is deliberate. "Not the type system" and "not a sandbox" are the two readings a reader supplies unprompted — the first cost four exchanges before the idea landed at all, and the second is the standard objection. Stating them costs one sentence and saves the reader from arriving at them alone.

"Refusing", not "skipping". Skipping is what Prepack does: residualise what you cannot evaluate, emit the rest. Refusal is per file with a fallback, and the wrong verb files you in the wrong family.

Cut

The comparison paragraph loses its third sentence, which the introduction now says better and earlier. Cut rather than reworded.

Left alone

The tagline. "Compiling TypeScript to configuration." is accurate and carries none of the axis, but a wordier one was rejected earlier and the tolerance there isn't mine to guess.

Verification

121 tests in 19 files, prose lint 51 with no regressions, npm run docs:build clean, and the rendered order confirmed from docs/public/index.html.

🤖 Generated with Claude Code

https://claude.ai/code/session_01AzfJnYw9p6rAxhJqXK3CPv