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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...

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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...

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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...

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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...

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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 ...

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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...

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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...

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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...

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July 21, 2025

Toby's Meetup Report: 31-Year Developer's Message on How to Live as a Developer in the AI Era

Yesterday (July 10), I attended a meetup titled [31-Year Developer’s Message on “How to Live as a Developer in the AI Era”] . It was a lecture by Toby hosted by Inflearn, and it was time where I could gain knowledge about core competencies required of developers in the AI coding era and AI collabor...

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July 11, 2025

From On-Premises to Cloud - A Zero-Downtime Migration Story

Hello, I’m Jeong Jeong-il, a 3rd-year backend developer working at a PropTech platform. In this post, I’d like to share my experience migrating a monolithic server operating in an on-premises environment to the cloud (AWS), and the infrastructure automation experience using Terraform during this pro...

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July 10, 2025