A local-only desktop app that turns a Korean school counsellor's three hours of monthly paperwork into ten minutes — ₩20M a month from under 100 schools, built solo with Replit and Claude Code
just under 100 paying schools of ~200 using · licences at ₩300K / ₩480K / ₩960K per year
Fewer bars = easier, cheaper, or faster for an AI-assisted solo builder. Editorial judgments based on the case details.
Min Sang-gi taught in Korean elementary schools for about fourteen years, then spent roughly a year working as a developer. When he saw what AI was becoming he quit and started building. He now runs two products; WeeNote is the one that worked. The idea arrived by accident. On Threads, a school counselling teacher posted that she was drowning in a specific administrative problem, had paid an Excel contractor to build her something, couldn't use what she got, and was asking for help. He messaged her, got on a video call, and recognised two things at once: the solution was not technically hard, and it would help someone immediately. He spent about three days without sleep and roughly $400 on Replit — which handled the database and deploys — and produced a prototype. That first version failed, and the reason is the most useful part of the story. His one user turned out to be the top 1% of her profession: she had spent her own money on custom tooling and knew how to brief a developer. Every feature she asked for was real, but the average counsellor never uses those features. He had built for a unicorn. Worse, when she demonstrated it to colleagues, the reaction was flat — not over features, but over the cloud. Counselling logs contain material so sensitive that some of it is deliberately never written down at all. He explained client-side encryption and keys the server can never decrypt; it didn't matter. The objection was that the log leaves the building over a network. A previous government-led program had died for the same reason. He interviewed more than twenty users. Seventy to eighty percent said the same thing: good product, wrong architecture. So he rebuilt version two as a local desktop app. Payments started arriving on launch day.
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Create free accountEmail code only. No password.Data credibility: Korean-language founder interview; everything is self-reported and no dashboard was shown on screen. The founder identifies himself as Min Sang-gi (민상기), a former elementary school teacher of about fourteen years who also runs a second service called IndiePub (인디펍). The revenue figure is his answer to a direct question about monthly revenue — "about ₩20 million" for March — hedged in the transcript with "I don't remember exactly", and corroborated only by his account of receiving a limit-exceeded email from Toss Payments against a ₩10 million monthly ceiling. Plan prices (₩300,000 / ₩480,000 / ₩960,000 per year) and the customer split (~200 schools using, just under 100 paying) are stated directly. We have not converted any won figure to dollars because the transcript never does. The EduZip listing, the provincial education office call, the Replit prototype cost (~$400, stated in dollars), the SQLite + Electron stack and the removal of "AI" from the product name are all as described by the founder. The transcript is a clean human-quality Korean transcript, not machine garble, so quoted details are reliable as *claims* — they are simply unaudited.