LambLisp — R7RS Scheme, compiled to WebAssembly

The same interpreter that runs on an ESP32-S3, built for wasm32 and running in this tab. Try (define (fact n) (if (= n 0) 1 (* n (fact (- n 1))))) then (fact 30).

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Your files — /persist, kept in this browser across reloads

(no saved files)

Saved files live at /persist and are readable from Scheme: (load "/persist/my.scm"). A file named autoload.scm is loaded automatically at start.

Runtime diagnostics (garbage-collector activity, evaluation traces) are silenced here so your own output is readable — type (verbose) to switch them on, (quiet) to silence them again.

This page demonstrates the LANGUAGE. It is not a performance demonstration and deliberately reports no timings: LambLisp's real-time claim is a bounded garbage-collector pause on a microcontroller, and a browser tab — with its own JIT, its own collector and its own tab throttling between you and the hardware — cannot show that either way.