Robust security on a commodity low-cost and popular computing platform is a worthy goal for today’s Internet of Things (IoT) and embedded ecosystems. We present the first practical security architecture on the Raspberry PI (PI), a ubiquitous and popular low-cost compute module. Our architecture and framework — called UBERPI — focuses on three goals which are keys to achieving practical security: commodity compatibility (e.g., runs unmodified Raspbian/Debian Linux) and unfettered access to platform hardware, performance (avg. 2%–6% overhead), and low trusted computing base and complexity (modular 5544 SLoC). We present a full implementation followed by a comprehensive evaluation and lessons learned. We believe that our contributions and findings elevate the PI into a next generation, secure, low-cost IoT embedded computing platform.