The European open compute architecture for powerful edge (CAPE) reshapes edge-cloud computing by developing edge micro data centres as a new unit of computing. Using a CXL-composable open hardware platform, it supports heterogeneous computing, using a COM-HPC form factor. Backed by a robust European ecosystem, this ensures broad adoption and fosters Europe’s digital sovereignty. Through a cloud-agnostic Infrastructure from code overlay, CAPE abstracts complexity across diverse infrastructures, enabling seamless edge-to-cloud deployment. It supports on-premise, off-premise, public and private clouds with minimal overhead. CAPE’s approach is validated in three use cases–managing intelligent electric microgrids, edge AI and satellite communications–each evaluating RISC-V and CXL solutions, comparing them against legacy hardware in local clouds and data centres.