Building Catch (https://catch.fyi), like a PagerDuty but with AI incident investigation.Catch helps on-call engineers quickly access relevant logs and metrics after an alarm and detects the root cause with AI— allowing them to resolve incidents faster.

#1 engineer. Built Cosmo—a fan engagement platform—to solve problems I faced as a KPOP fanLaunched a KPOP girl group called tripleS.

Built Airbridge as #1 employeeDB Engine Development - Built an in-house distributed database optimized for real-time OLAP query. - Developed an open-source MapReduce framework in Go (https://github.com/ab180/lrmr) - Developed JiT query compiler with LLVM, and integrated it with a C/C++ storage engine - Designed SIMD column-store storage format optimized for distributed data processing. - Experience in Go performance optimization & handling memory leaks - Presented at NAVER Deview 2020 (the largest dev conference in South Korea)DevOps- Operated Kubernetes cluster in production with Amazon EKS- Optimized the infra cost with dedicated node group setup and cluster autoscaling- Monitored cluster/app with Prometheus, Grafana and PagerDuty- Increased infrastructure auditability by high-coverage IaC through Terraform with KubernetesData Engineer- Worked on batch data ingestion from Snowflake to our DB engine with Airflow

- Postback Request System using Golang - Built Continuous Deployment Pipeline using Docker and Amazon ECS- Batch Dump Exporter using Spark- Android App Manifest Data Crawler using Scala

Airbridge SDK for Android (Installed over 40 million devices)- SDK Architecture, API, and the features- Experience on handling fragmentation issue of various Android versions- Automated unit tests and end-to-end instrumentation tests - Continuous Delivery Pipeline using Jenkins / CircleCI- Experience on project management

- Personal schedule management assistant service, as a side project- Reached 20K+ users, App Store rank #70, and featured on the main page— after 1mo of the release