§ 4 — ABOUT
Yechan Kim
nerdchanii
INTRO
I'm Yechan Kim. I build systems where agents work on their own, and stop to ask where a person should decide.
At 42 Seoul, building a shell in C and an IRC server in C++ taught me how programs actually run on an operating system. At boostcamp, building RAG and agents showed me that results depend less on the model than on how you design around it. Now I bring the two together: deciding how much to hand to an agent and where to ask a person.
When I hit a bug, I follow it past the symptom to the cause, and try to give it back as a reproducer, an issue, or a PR.
THREE AXES
- AGENTSAgent engineering: tools, state, and where a human steps in.
- ROOT CAUSETrace symptoms to causes, then give back a repro and a fix.
- SYSTEMSTools built from the ground up, from a C shell to a Rust package manager.
HOW I WORK
Agree on words first
When the same word means different things, the design wobbles. On MIT, the domain glossary came first.
Contracts before code
Pin down inputs, outputs, and invariants first; decide where to stay flexible and where to be strict.
Measure, don't assume
Judge by reproduction, tests, and records rather than self-reports or hunches.
PATH
- 2020 – 2023Computer Science, Korea National Open University
- 2022First side project, Code Sparring: solving coding tests together in real time
- 2023 –42 Seoul, 10th cohort: a shell in C, an IRC server in C++, a multiplayer web game as a team
- 2025 – 2026NAVER boostcamp AI Tech, 8th cohort (NLP): MRC, MCQA, and the final project MIT
- 2026Codex cache bug analysis, merged PRs in the SolidJS ecosystem, work on agent autonomy and human boundaries
CONTACT
Issues, PRs, or collaboration ideas — reach me on GitHub.