
CEO Lee Yunseok
Mogakgong (Doubletimemarch Inc.)
IT Consulting
Hello π I am Lee Yunseok, CEO of Doubletimemarch Inc., which operates Mogakgong, a verification-based cafe study app for growing youth. I majored in Public Administration, Business Administration, and Computer Science at Yonsei University, and completed a Master's degree in Data Science at Seoul National University Graduate School.
I first met Hyunjae in 2020 on Soomgo as a Flutter teacher and student. Through various twists and turns, after another developer suddenly quit the project with 30 million won invested, I contacted Hyunjae. He willingly accepted the request and rebuilt the entire system in just 2 months for the demo day. We officially launched version 1.0.0 in 5 months, and exceeded 500 registered users within 1 month of app launch.
What I felt most deeply while working with Hyunjae was that he is not just a developer who codes well, but a person who keeps his word. He works with a sense of responsibility as a conviction. Whenever we talked, I heard "Yunseok, I will take responsibility for this." Even when things got much bigger than expected, he didn't make excuses or delay, but persistently solved problems until the end. That one sentence was the biggest support for an entrepreneur whose default state is anxiety.

Hyunjae is not just a developer, but more like an IT consultant who can plan. Many features that I hadn't fully considered in the initial planning stage (coffee map, mentoring, event board, anonymous board structure and matching method, Mogakgong in-app payment ecosystem, recommendation algorithm, etc.) were all refined and developed through conversations with Hyunjae.
Another great advantage is that Hyunjae is a developer who can also design, so we were able to launch the mobile app without hiring a separate UI/UX designer. Thanks to Hyunjae's design aesthetic, we saved all the time and budget that would have been spent on UI/UX designers, while still launching an app with excellent functionality and aesthetics. This allowed me to invest more budget in other important areas such as development and marketing.
Also, Hyunjae has exceptional depth of development and density of intelligence. Mogakgong is "an ecosystem" that encompasses authentication system, ERP/admin, server structure, matching algorithm, in-app payment, boards, chat, and landing. Most outsourcing companies only implement functions right in front of them, but Hyunjae redesigned the entire system with an architecture considering 3 and 5 years ahead.

Hyunjae was also like a pacemaker to me. His driving force is very fast and strong, but when I was worried or my decisions wavered, he respected my pace and waited. Whenever I couldn't find my way among various options, he calmly guided me without being impatient.

I can say with certainty. Hyunjae is a rare developer who has development ability, speed, stability, planning, consulting, character, and credibility all together. And I can say sincerely. With Hyunjae, any difficulty and any crisis will eventually be resolved. And this review is a record proving that fact.