This repository is the NumWorks Epsilon operating system and firmware for a graphing calculator. It is a complete software stack including a custom GUI framework (Escher), a symbolic math engine (Poincaré), a MicroPython interpreter, numerous educational apps (calculation, graphing, statistics, inference, finance, sequences, etc.), and low-level hardware drivers (Ion) for real devices and a cross-platform SDL-based simulator. The architecture is monolithic: all components share a custom memory pool, a responder-based UI framework, and a common record-based persistent storage system. Key entry points are the bootloader, the Ion::Main function, and an app container that launches snapshots of each app. The system handles user input through keyboard events, renders via a 2D graphics library (Kandinsky), and persists data (scripts, preferences, calculations) in a file-system-like record store. External dependencies include a vendored SDL 2.0 (for simulation), a bespoke MicroPython port, OpenBSD math functions, and an embedded SQLite memory allocator. While the math engine and many apps are well-crafted, the large third-party code and numerous platform backends introduce moderate technical drift risk.