recheck is a monorepo for a ReDoS (Regular expression Denial of Service) vulnerability checker, written in Scala 3 and cross-compiled to JVM and JavaScript via Scala.js. The system parses regular expression patterns, builds an execution model, and detects catastrophic backtracking vulnerabilities. It exposes multiple interfaces: a core library (`recheck-core`) with a high-level `ReDoS.check` API, a CLI (`recheck-cli`) with `check` and `batch` subcommands (the latter using JSON-RPC over stdio), JavaScript bindings (`recheck-js`) for browser/Node usage, and an ESLint plugin (`eslint-plugin-redos`) for CI integration. The architecture is a multi-module sbt build with Lerna/pnpm for JS workspace management, featuring clean separation between parsing, execution, unicode data, and platform-specific adapters.