Hi Product Hunt 🤍 I'm Casper. I built Cotidie because I'm the worst journaler I know. Every notebook I've started died at week three. Every "AI journal" I tried did one of three things that made me close it: generated content I'd never write, scored my mood out of ten, or shamed me for skipping a day. So I built the opposite. → Cotidie doesn't write for you. You write a few sentences a night. The AI reads them — slowly, over weeks — and quietly surfaces patterns you'd been making without noticing. It hands you back what you'd already been writing. → There's a Private Vault that lives on your device only. Never synced. Never seen by the AI. Biometric-locked. Took us one stubborn month to wire that part right — and we have nothing to do with it after. → Seven AI personas. Sage when you want a guide. Kai when you want truth. Ash when you don't want a coach — just someone who sits with you. Not every night needs the same kind of company. → No streaks. No feed. No mood scores. No public profile. The rarest feature in 2026, honestly. I'd love to know — what would make you actually keep a journal? And what would you want from one that reads itself back? Thank you for reading. — c.

Cotidie

The AI journal that reads you back.

The AI journal that reads you back.