Solving GitHub Actions Free Tier Limits: Our Journey from Self-hosted Runners to Jenkins
Hello! I’m Jeongil Jeong, a 3-year backend developer working at a proptech platform. This is the story of trial and error we experienced while improving our CI/CD pipeline at the company. I’d like to share our journey from starting with GitHub Actions, through Self-hosted Runners, to finally settlin...
December 16, 2025
My Journey to Passing the CKA (Certified Kubernetes Administrator) Exam
Introduction Hi, I’m Jeongil Jeong, a backend developer with 3 years of experience, currently working at a proptech platform. Containerization has become increasingly important in modern web server deployment. In the past, it was common to install and operate web servers like Tomcat directly on virt...
December 1, 2025
What is Manticore Search? Configuration, Setup, and Practical Application
Hello. I’m Jeongil Jeong, working as a backend developer at a PropTech platform. “We need a search feature.” When you hear this, one name probably pops into most developers’ heads. That is Elasticsearch. Thanks to its powerful features and rich ecosystem, it seems to be considered the industry stand...
November 25, 2025
APIs Slowing Down After Deployment: Improving JVM Cold Start Problem by 85%
Introduction Recently, our team migrated from a Docker Compose-based production environment to Kubernetes. It was a choice to properly utilize features needed in an MSA environment, such as scalability, automation, and zero-downtime deployment. Related article: From No Dev Server to GitOps: My Journ...
November 18, 2025
Have I Embraced the Future? - How Developers Collaborate with AI Coding Tools
Hello. I’m Jeongil Jeong, a 3rd-year backend developer working at a proptech platform. These days, the weight of AI coding tools among developers is gradually increasing. GitHub Copilot, ChatGPT, Claude Code… Many developers are already using them, and there’s even talk that “you’ll fall behind if y...
October 25, 2025
Changed MySQL Column Type from bigint to varchar and It Got 8x Slower...! : Procedure Performance Degradation Troubleshooting
Introduction Hello. I’m Jeongil Jeong, a 3rd-year backend developer working at a proptech platform. Today, I’d like to share an interesting performance issue that occurred in our service and the resolution process. While solving a problem where a MySQL procedure suddenly became 8 times slower, I enc...
October 20, 2025
From 16 Repositories to One - MSA Multi-Module Migration Story
Introduction Hello. I’m Jeongil Jeong, a 3rd-year backend developer working at a proptech platform. In March 2025, I joined the team and went through the process of converting 16 backend projects managed in individual Repositories into a multi-module structure based on a single Repository. I’d like ...
October 16, 2025
3 Ways for Developers to Quickly Adapt to a New Company
Hello. I’m Jeongil Jeong, a 3rd-year backend developer working at a proptech platform. Job changes are not easy for anyone. New codebase, unfamiliar team culture, unknown business domain… I was also at a loss when I joined a new company. Today I want to share how I adapted to the new company and the...
September 30, 2025
From No Dev Server to GitOps: My Journey of Introducing Kubernetes from Scratch
Hello. I’m Jeong Jeong-il, a 3rd-year backend developer working at a PropTech platform. Today, I’d like to share the process of migrating our MSA services, which were running on a legacy Docker environment, to a Kubernetes-based infrastructure, a journey I proposed and built from scratch. The bigges...
July 24, 2025
Is Gradual MSA Transition an Illusion? - Battling with Tightly Coupled Legacy Services
Hello, I’m Jeongil Jeong, a 3rd-year backend developer working at a proptech platform. I joined the team recently in March, and like many companies, our team was undertaking the grand journey of transitioning legacy services to Microservices Architecture (MSA) for better scalability and maintainabil...
July 21, 2025