One
A proof is a tree you grow by hand.
The theorem sits at the top, unproven. You work backwards until every branch ends in something already known.
Two
Every step is checked by a real verifier.
There is a proof kernel inside this app. It refuses anything that does not follow. When it says you proved it, you proved it.
Three
You will never type mathematics.
Suppose, split, take cases, name a witness. Eight moves carry the whole game, and the first one is waiting.
The grand map
0
Twenty five centuries, three regions, one kernel.
One theorem, the same one for everyone, chosen by today’s date.
The grid shows the shape of your proof tree and nothing else. It gives no step away.
The last thirty days
Dailies are computed from the date on this device, so they work with no connection and everyone gets the same theorem.
Drills, built fresh each time
The Forge
Pick a move and the forge grows a new theorem around it, then checks that it can be finished before handing it to you. Mastery fades over a few weeks, which is what brings you back.
Everything you have proved
Satchel
Every theorem you finish becomes a tool you keep. Tap any one to watch your own proof rebuild itself, step by step.
Nothing yet. Prove one theorem and it becomes a tool you keep.
Kept on this device only
You
Rigor
Seals
Daily streak
Gold crowns
Silver crowns
Rigor is a local score. There is no server behind it and no leaderboard to climb, so it only ever measures you against the shortest known proof.
Settings
Woodblock clicks and the closing chord, synthesised on the device.
A short thunk when a step snaps home.
One notification a day, only until you have solved that day’s proof. Off by default.
Your progress
Everything lives in this app’s storage on this phone. Nothing is uploaded, because the app cannot reach the network at all.
Axiom. Rigor as play.
Free, complete, and offline.
Moves
Satchel