Lunatik is a framework for scripting the Linux kernel with Lua
A lightweight online game framework
Tools for BPF-based Linux IO analysis, networking, monitoring, etc.
BizHawk is a multi-system emulator written in C#
3D game engine/framework in C, with Luajit and Python bindings now
Capstone disassembly/disassembler framework
Unicorn CPU emulator framework (ARM, AArch64, M68K, Mips, Sparc
Developer Assistant for PUC-Rio Tecgraf sci/tech toolkits on GNU/Linux
A vi-like editor based on Plan 9's structural regular expressions
Lua based interactive firmware for ESP8266, ESP8285 and ESP32
Powerful embedded Lua Engine for IoT devices, with many components
An Apache module for developing web applications using Lua