Jangchun L.

Full-stack developer with professional experience at a U.S. enterprise software company, where I build and maintain Angular + C#/.NET business applications on a distributed team — PR-based workflow, daily code reviews, and direct collaboration with U.S. engineers in English. Outside my day job I design, build, and ship my own products end to end. My screen-time management app D.off is live on Google Play (Angular + Capacitor + Firebase), with more in the pipeline: a sobriety-support app in final release, a daycare–parent communication app in closed testing, and an on-device pronunciation-training app that reached the top-10 finals of a Korean app development competition. What I can help you with: - Responsive web applications (Angular, React, TypeScript) - Cross-platform mobile apps (Capacitor, React Native / Expo) — from first build to store release - Back ends and APIs (C#/.NET, Java, Firebase, MySQL, AWS) - Taking an idea from a rough spec to a published, working product I work hourly or fixed-price, communicate proactively in fluent English, and deliver fast — I use modern AI tooling to move quickly, and verify everything by hand before it ships.