Both builds exit 0.
Only one ran your transformer.
one tsconfig.json: "plugins": [{ "transform": "./transformer.cjs" }]
tsc 6.0.3 + ts-patch
OUT/TS6/APP.JS
debug('largestOrder received ' …);
debug('largestOrder chose ' …);
transformer ran0 debug() calls left of 2
exit 0 ✓
tsc 7.0.2 · the Go port
OUT/TS7/APP.JS
debug('largestOrder received ' …);
debug('largestOrder chose ' …);
transformer skipped2 debug() calls left of 2
exit 0 ✓
and not one warning
TypeScript 7 accepts the plugins entry without a word, while it rejects an option it has never heard of with error TS5023. It ships with no JavaScript API, so there is nothing left for a transformer to hook into.