Developer Career Retrospective: No Fixed Algorithm, 10 Years Scripted by My Own Logic

This post is a record of how I have lived the past 10 years and how I intend to live in the future.

Looking back, it was a time filled with numerous challenges and just as many failures. Throughout that intense process, I constantly asked myself, "What kind of life do I want to live?" The next 10 years will likely be no different. I suspect I will continue to challenge myself, stumble, and yet rise again.

This is a memoir to mark the end of my 20s and the new beginning of my 30s. I would appreciate it if you read it lightly, perhaps thinking, "Ah, so there is someone who lives like this."

Prologue

My 20s Began with a 'Compile Error'

In 2017, my life felt like it threw a 'Compile Error' right from the start. For me, who believed that a 'prestigious university' was everything in life, failing the entrance exam for the second time left me with a lingering question: "Is my life a failure?"

Although I lived diligently as a mechanical engineering student, my future felt like a terminal window I was seeing for the first time—the cursor blinking, but with absolutely no idea what command to input. That is my memory of my early 20s.

I didn't know it then. I didn't realize that designing my own "life logic" was far more important than following the famous logic of "Admission to a Top University → Employment at a Top Corporation."

v1.0 The First Commit

Creating My Own Repository, Not Someone Else’s Answer

Ironically, the place where I decided to walk a different path from others was the place where everyone wears the same clothes and walks in the same step: the military, the most strictly controlled space in Korea.

Meeting people from diverse backgrounds there, I realized something. The world didn't run on just one algorithm called "SAT-College-Employment."

I started looking for answers to design my own life, and I found clues in books. (To be honest, I still don't know if they were the right answers.) I devoured countless investment and self-development books in the barracks library, and the conclusion was clear: To live my own life, I had to do business and investment. But with nothing to my name and no skills, what could I do right away?

My first step into programming wasn't to become a developer. It was merely a tool to build my business with my own hands. Nothing more, nothing less. (At that time, I never imagined I would make a living out of programming.)

v2.0 Unit Test Passed

Debugging the Bug Called 'Defeatism' and Validating Possibility

I was able to escape defeatism thanks to En# (a computer club at Sejong University). Seeing seniors who went on to top-tier companies or succeeded in their own businesses, I thought, "If I work hard here, I can become like them." I immersed myself in programming with my clubmates and built up my skills.

Effort did not betray me. A senior's remark that "I think he's going to be the best later on," combined with winning competitions and becoming a Microsoft ImagineCup World Finalist, deleted the deep-seated thought that "I'm a guy who fails at everything."

With newfound confidence, I immediately jumped into what was perhaps the biggest challenge of that period: Startups.

Joining as a founding member of the designated blood donation platform 'People', I evolved into an 'All-rounder.' From planning to development, QA, and Investor Relations (IR). Experiencing the entire cycle where user voices are implemented into code and return as business results, I finally acquired the perspective of an 'Entrepreneur who Develops.'

v3.0 Continuous Integration (CI)

Refining the System Through Repeated Failures

From 2022, I fully committed myself to entrepreneurship. This period was like a massive CI (Continuous Integration) pipeline for me. It was an intense sequence of writing code, crashing into reality, analyzing error logs, and refining the system.

Integration 1: Optimization Under Constraints (F&B Fractional Investment Platform) My time at the 'Burning Surprise' team was an extreme environment where I had to cover all resources with personal funds and handle everything from planning to infrastructure alone within a short timeframe. I had to integrate conflicting constraints: 'Cost Optimization' and 'Financial Security.' Although we achieved meaningful traffic—reaching 30 million KRW out of a 300 million KRW funding target—we eventually had to shutdown the service due to realistic issues. However, through this process, I mastered the method of Optimization to squeeze out the best performance with limited resources.

Integration 2: Expanding Infrastructure Capabilities (Drag-and-Drop Cloud SaaS) This project, attempted during the Software Maestro course, was based on the ambitious idea: "You draw the architecture, we handle the deployment." Although it didn't reach the commercialization stage, the capabilities I gained in IaC (Infrastructure as Code), IAM management, and complex Network Design became practical muscles that no classroom lecture could ever provide.

Two service shutdowns. But these were not simple bugs. They were a necessary 'Refactoring' process to build a more robust architecture as an engineer.

v4.0 System Scale-Up

Expanding Skills and Capacity on the Financial Domain

In 2024, exhausted by successive challenges, I briefly chose to compromise with reality. I worked as a freelancer for livelihood and simultaneously went through an internship at KB Data Systems to prepare for a stable corporate job.

But this time was never a period of stagnation. Rather, it was a time where I simultaneously grew my 'Technical Skills' and 'Business Sense.'

Freelancing was a real-world communication boot camp. I cultivated the problem-solving ability to identify the 'Core Requirements' hidden behind the vague requests of clients and planners and implement them clearly into software. Also, by handling everything from customer service to contract execution, I physically learned the practical flow of business.

At the same time, at KB Data Systems, I learned enterprise-level standards. By analyzing strict financial RFPs and designing On-Premise Infrastructure accordingly, I embodied the robustness and specifications required by large-scale systems.

In the midst of this, an offer came from a startup dealing with 'Investment' and 'Finance,' which had always been my interests. The option of stable corporate employment was right in front of me, and startups were still an unstable wildland. Yet, my heart still desired 'Growth' and 'Challenge' over 'Stability.'

And so, I dove back into the startup ecosystem. After working at a Real Estate PF (Project Financing) company, I am currently working as a developer at a US Stock Asset Management startup.

This choice was not wrong. In the wild, practical environment, I absorbed Financial Domain Knowledge that other developers rarely get to experience. From building Data Pipelines to developing high-performance APIs, designing DBs for large-scale processing and query optimization, to building/operating Kubernetes and Cloud Services. I have stacked core financial IT capabilities on top of my skills in a compressed period of time.

Now, I am not just a developer who churns out code according to a functional spec sheet. I am growing into a Software Engineer who reads the flow of complex businesses using the skills learned during my startup/freelance days and translates those Requirements into the most efficient technology.