Birda.

Birda is the government service through which phones get registered in Uzbekistan. Isfan built the app serving 400,000+ users: Face ID identity verification, online customs duty payments, and eSIM activation — flows where a failure isn't a bad review, it's a citizen who can't use their phone.

Government scale means compliance constraints, identity verification that has to be right, and payments that have to clear. This is the proof that he ships under rules, not just under deadlines.

He also implemented the analytics and observability stack — Firebase, AppMetrica, Mixpanel, and Sentry — so the team sees real usage and real crashes across a 400K-user fleet instead of guessing.