Engineer shares battle-tested C++ rules for safer, faster embedded systems code

A software engineer has published a set of personal coding principles developed over a full career, shaped by colleagues across many projects and code reviews. The rules are designed to make C++ code both safer and faster, particularly for embedded systems running on ARM Cortex-M33 and M7-class microcontrollers. Four core disciplines guide the approach: strict memory and mutation control, a single consistent numeric type, mandatory error handling, and minimising hidden dependencies. The constraint of targeting low-resource microcontrollers — where a single stray heap allocation can break real-time audio deadlines — drove the elimination of dynamic memory allocation in signal paths. The author frames the rules not as fixed doctrine but as evolving lessons, crediting a broad group of collaborators for helping develop and refine them over time.