nan-boxing

Single-pass SSA compiler and tiered register VM for a sandboxed Python subset, with NaN-boxed values, inline caches, memoization, mark-sweep GC and snapshots. One WebAssembly module runs in browsers, JavaScript runtimes and the CLI.

望舒 Wangshu — A high-performance embeddable Lua 5.1 VM in pure Go (no cgo): NaN-boxing, arena GC, inline caches, coroutines, and a tiered method JIT (interpreter → wasm → native amd64/arm64). Up to 17x faster than gopher-lua on numeric kernels, byte-equal with PUC Lua 5.1.5.

a fast, lightweight programming language built in portable c11 with a custom bytecode vm.

NaN boxing in Zig

Tracing JIT compiler for the Wren scripting language

A demonstration of NaN boxing for runtime type checking

Not your average AI slop: A reasonably robust, fully tested statically typed language and bytecode VM, 100% authored by Opus 4.8

An ahead-of-time JavaScript/TypeScript to WebAssembly compiler in Rust, with conformance tracked by test262. swc frontend, wasm-encoder codegen, wasmtime runtime — no JIT, no interpreter.

恋语——中文编程语言 | LLVM JIT/AOT 工业级性能 | 开源免费

r8e — r(unmachin)e: A secure, minimal JavaScript engine in 166KB. ES2023 compliant. No JIT. Deterministic GC. Five-layer security. Built-in UI rendering.

Experimental Forth-like VM using doubles and NaN-boxing as data representation.