Engine assets
Regex Tools executes ECMAScript through the browser's native RegExp engine.
It also ships three declared, self-hosted runtime packs:
pcre2/: official PCRE2 10.47, 8-bit WebAssembly;python/: Pyodide 314.0.3 with CPython 3.14.2re; andjava/: TeaVM 0.15.0'sjava.util.regexclass library compiled to an ES2015 module. This module is not OpenJDK.
The packs come from pinned, documented open-source inputs. Runtime files travel with deterministic metadata, closed-set checksums and the applicable upstream licence/notice material, all of which are verified by the release gate.