Nemmy

It started from two problems: nothing prompts you to go to bed, and a sleep habit never sticks. From the lock screen you can see how many friends are already asleep.

Set a bedtime goal and the app restricts content while you are missing it. You post one moment from the day to look back on, send stamps to your friends' posts, and watch the background shift with the hour all the way to dawn.

As a team, we drew the glowing starfield with Metal and pulled sleep depth and duration from HealthKit. The infrastructure was defined in Terraform, and we kept the AWS bill to ¥450 a month.