Byungwoo Yoo

CTO / Software Engineer

Summary

Inspired by a professor's words, 'You have received the best education at a lower cost, so you must dedicate yourself to the country and its people,' I have worked as a core developer for LINE Messenger, used by 600 million people worldwide, and have experience in entrepreneurship and exit in the US. I have also led AI labs at top ed-tech companies in Korea and currently serve as CTO at Datarize.

Experience

Datarize

06/2025 - 06/2026

CTO

CRM SaaS platform for e-commerce operators

  • Established technical roadmaps and managed hiring and organization for BE, FE, Data, QA, and SDK chapters
  • Led AX transformation across the company and drove AI hackathons, resulting in the launch of three AI products
  • Designed enterprise-oriented APIs and handled technical sales

Mathpresso

02/2021 - 05/2025

VP of Engineering / AI Lab Lead

Operator of QANDA, an AI-based math problem-solving search platform

  • Led the only profitable B2B business unit, providing AI solutions to major educational companies such as Mirae, Visang, and YBM
  • Led multiple AI research projects, including ML, search, and automatic calculator and content DB development
  • Redesigned search and ML services based on domain-driven design, reducing infrastructure costs by over 50%

Kasa Korea

02/2020 - 02/2021

VP of Engineering

Operator of Kasa, a blockchain-based real estate investment and trading platform

  • Oversaw the development of various features for API servers and trading engines, leading to the successful launch of the service

Buzzvil

01/2017 - 02/2020

Team Lead

Operator of Buzzscreen, the world's largest smartphone lock screen advertising platform (used by over 2 million people daily)

  • Developed and managed ad and content allocation logic for Buzzscreen
  • Optimized search functionality, reducing infrastructure costs by 75% and improving response times
  • As a software architect, guided other engineers in building robust and sustainable microservices using Clean Architecture and DDD, ensuring zero downtime

Slidejoy

09/2014 - 01/2017

Co-founder

US-based startup acquired by Buzzvil

  • Reached break-even point and secured funding before being acquired
  • Designed and developed the service using ad networks, and introduced Spring Boot for the backend

NAVER

12/2011 - 03/2015

Senior Software Engineer

Core developer for LINE Messenger

  • Improved transmission rates (75% to 99.5%) as the lead developer for NNI (NHN Notification Infra), a core library for LINE, and gained experience with overseas deployments and on-site debugging
  • Developed and contributed to the Android version of the Netty network library as open-source
  • Introduced MVP software design, significantly enhancing team performance

InfoBank / DOSA

05/2008 - 12/2011

Software Engineer

Worked at InfoBank and DOSA as part of my military service

  • Participated in the development of m&Talk and Samsung ChatON

Volunteer

Gyeonggi Province

09/2024 - 05/2026
Provincial Policy Advisor (Economic Investment Division)

Provided AI policy and technical advice to Gyeonggi Province

  • Advised on the construction of Gyeonggi Province's generative AI project and conducted technical reviews

Publications

Explain with Visual Keypoints Like a Real Mentor! A Benchmark for Multimodal Solution Explanation

04/2025
AAAI 2026 (arXiv:2504.03197)

Proposed a multimodal benchmark (MathExplain) for identifying and explaining visual keypoints in math problem-solving explanations. Co-authored.