216 passing tests. A feature that was completely broken. Here is the gap between those two facts, and what I changed afterwards. The feature I am building an encrypted messenger. Messages are end to end encrypted, and the server relaying them cannot read anything. That part worked. What I added was offline delivery. If you message someone whose app is closed, the server should hold the message, hand it over when they come back, then delete it. Nothing kept longer than it needs...