This repository contains the full firmware for NumWorks graphing calculators. It is a complete, self-contained operating system targeting ARM Cortex-M7 hardware, providing a suite of educational mathematics applications (graphing, statistics, calculus, finance, sequences, inference, etc.), a MicroPython interpreter with numpy-like arrays and plotting, a symbolic math engine (Poincaré), a custom UI framework (Escher), and hardware abstraction layers (Ion). The architecture is modular: each app is a compile-time plugin sharing a common responder-based event handling system, a view hierarchy, and a persistent storage layer. User input flows through the ion keyboard/touch drivers into Escher's responder chain, which dispatches events to controllers that manipulate mathematical or statistical models, triggering view redraws via Kandinsky (2D graphics). The system includes bootloaders, USB DFU support, and exam-mode enforcement. External dependencies are minimal at runtime (entirely embedded); build-time dependencies include SDL for simulator builds, MicroPython and ulab sources (vendored), and standard C++ toolchains.