Mobile social network for French student associations. 50 active associations, thousands of events organized, integrated ticketing. Launched in 2022, sunsetted in 2026 by client decision (strategy change, no technical issue).
Build a full social product (feed, paid events, real-time chat, moderation) with viable unit economics on a student user base — meaning an infrastructure budget that had to hold at €3-4 per active user per year, not per month.
Flutter stack for iOS + Android on a single codebase. Express + Mongoose (MongoDB) backend deployed on AWS Elastic Beanstalk in eu-west-3, with multi-AZ auto-scaling and PM2 in cluster mode to absorb the peaks (concentrated on Thursday evening student parties). MongoDB for feed and chat, S3 for files, Firebase for push notifications. Multi-tier ticketing (free, paid, multiple prices, bundles, member or non-member rates, waitlist) with ticket payments via Lydia.
3 years 4 months in stable production. Programmed sunset in 2026 without technical incident. Code base fully transferred to the client.