The rapid adoption of cloud-native technologies, particularly containerization and orchestration with systems like Kubernetes, necessitates their effective integration into undergraduate computer science curricula. However, the complexity of production-grade cloud-native systems present a steep learning curve. Traditional pedagogical approaches often involve either oversimplified toy projects built from scratch, which lack real-world relevance, or the direct use of complex cloud systems, which can obscure fundamental concepts. To overcome these barriers, we introduce miniK8s, a lightweight, Kubernetes-like platform designed for an undergraduate cloud computing course. miniK8s distinguishes itself by promoting the pedagogical vision of teaching students to build a substantial and realistic system by integrating existing, robust open-source components with a hand-written, simplified cornerstone component. With miniK8s, students can both learn the key concepts inside the cloud architecture (e.g., resource scaling) and build practical systems with open-source building blocks. We have successfully used miniK8s as a project in a cloud computing course for hundreds of undergraduate students, which can significantly enhance students’ understanding of how real-world cloud-native systems work and their ability to build a complex system.