From Athenz to Kubestronaut: From Necessity to Expertise

Starting from work as a security platform engineer at LY Corporation developing and operating Athenz, the process of deeply learning Kubernetes ultimately led to earning Kubestronaut status.

At first, since Athenz needed to be stably deployed and operated in an internal KaaS environment, CKAD was set as the goal. It was a choice made to understand Kubernetes from an application perspective, and preparation involved studying briefly every weekday morning, at least 1 hour on weekends, and more than 12 hours of immersive study on the weekend right before the exam. In particular, repeatedly practicing problems harder than the actual exam using killer.sh was a huge help.

As the role grew larger, it became necessary to understand the cluster itself beyond just the application level, and CKA was chosen as the next step. While preparing for CKA, it became clear that Kubernetes is not simply an automation tool but a sophisticated system where multiple components are organically interlinked, and a lesson was also learned that when designing large systems, responsibilities must be clearly divided and the structure kept simple.

Since security is a core area of expertise, the final piece of the puzzle was CKS. Known as the most difficult hands-on exam, it became an opportunity to systematically refine practical skills such as cluster hardening, security best practices, vulnerability analysis, and configuring NetworkPolicy. Afterward, KCSA and KCNA were also obtained, completing all 5 certifications, and the name was added to the Kubestronaut list on the CNCF website.

The biggest takeaway from this process was gaining a deeper understanding of open source governance and how the community works, more than the certifications themselves. Observing how Kubernetes grows through SIG and PR rules also provided a new perspective on the team's strategy for advancing Athenz from sandbox to incubating stage.

The learning also translated into actual work results. In the currently ongoing Athenz deployment for a bare metal as a service environment, the architectural sense built up during certification preparation made it possible to design a more stable and efficient structure and explain it persuasively to the team.

Waking up every day at 4:30 a.m. (sometimes 3:00 a.m.) to exercise, leaving at least 1 commit on GitHub, and continuing to study even briefly became the foundation of consistency. The company's Udemy Business, hybrid work, and department-level certification support programs were also key conditions that accelerated the pace of growth. In the end, Kubernetes learning that began in order to do necessary work well turned into a journey of deeply understanding one of the most favorite technologies.