Yung Yoon
Software Engineer at Korea Credit Data
Seoul, South Korea
Summary
👤
Senior🎓
Top SchoolYung Yoon is a Principal Software Engineer and systems architect with 13+ years building data-as-substrate platforms that turn behavioral signals into product decisions across ads, recommendations, and AI-native features. He founded Apache S2Graph at Kakao, running trillions of edges and driving measurable business lifts (20–30% CTR gains) while enabling sub-day experiment integration across 30+ services. As CTO at Korea Credit Data he migrated a 40TB OLTP bottleneck into a Spark pipeline (≈10× latency, ≈100× cost improvement) and launched a $1.5M ARR DSP, and today he is the sole architect of Decision OS at Liner—an end-to-end candidate-filter-rank platform powering retrieval, RAG, and LLM-driven ranking in production. His work repeatedly targets the missing substrate: build it, let value drive adoption, then generalize the pattern—an approach honed since a formative Google internship and proven across Kakao, KCD, LBOX, and Liner. He holds two international patent families and a track record of donating production-grade infrastructure to open source.
13 years of coding experience
14 years of employment as a software developer
B.S, Electrical Engineering, B.S, Electrical Engineering at Korea UniversityStudent Exchange Program, Computer Science, Student Exchange Program, Computer Science at The University of British Columbia
English, Korean
Github Skills (19)
java10
apache9
distribute9
database8
scale8
graph-database8
graph8
large-scale8
hbase-client7
thread6
blocking6
hbase6
async5
non-blocking5
asynchronous5
Programming languages (4)
Github contributions (5)
SteamShon/UserAuthenticatationBase
Jul 2012 - Aug 2012
Contributions:101 commits in 1 month
SteamShon/incubator-s2graph
Jan 2016 - May 2019
Mirror of Apache S2Graph (Incubating)
Contributions:15 PRs, 310 pushes, 164 branches in 3 years 4 months
javaincubatingapache
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