@jsy-lang/jsy (formerly jsy-transpile)

JSY is an offside-rule (indentation-based) syntax dialect for ECMAScript that transpiles to standard JavaScript via a scanner-pass transformation, without Babel, Acorn, or any runtime dependencies. Current stable version 0.10.9. It supports modern JavaScript up to ES2025, has zero dependencies, 6300+ unit tests, and works with Rollup, ESBuild, Parcel, Vite, and Node.js --loader. Unlike CoffeeScript or Python-inspired alternatives, JSY automatically keeps pace with new ECMAScript features because its transformation only handles indentation and comments, leaving the underlying JavaScript syntax untouched. The package was renamed from jsy-transpile to @jsy-lang/jsy.