Semantic IR. 11 Targets. Self-extending.

Why it works

KERN isn't regex. It's a semantic IR.

Rules operate on meaning, not text patterns. That's why KERN catches what regex-based tools miss.

One source, every target

Same .kern. 11 outputs.

KERN compiles to Next.js, React, Vue, Express, FastAPI, React Native, CLI, Terminal, Ink, Nuxt, and Tailwind. One source file, every stack.

machine name=Order initial=pending
  transition from=pending
    to=confirmed event=confirm
  transition from=confirmed
    to=shipped event=ship
  transition from=shipped
    to=delivered event=deliver

export enum OrderState {
  Pending = 'pending',
  Confirmed = 'confirmed',
  Shipped = 'shipped',
  Delivered = 'delivered',
}

export enum OrderEvent {
  Confirm = 'confirm',
  Ship = 'ship',
  Deliver = 'deliver',
}

const transitions: OrderTransition[] = [
  { from: OrderState.Pending,
    to: OrderState.Confirmed,
    event: OrderEvent.Confirm },
  // ... + type guards, transition fn,
  // exhaustive checks (140+ lines)
];

Self-extending

The language that extends itself.

kern evolve discovers patterns in your codebase, proposes new syntax, validates it through 9 steps, and extends the language. No other language does this.

$ kern evolve:discover src/

Found 3 recurring patterns:

  1  auth-guard-pattern
     Appears 12x across 4 files
     guard auth.check() before db.write()

  2  api-response-shape
     Appears 8x across 3 files
     { data: T, error?: string, status: number }

  3  retry-with-backoff
     Appears 5x across 2 files
     retry(fn, { max: 3, backoff: 'exponential' })

? Promote to language construct? [y/N]