Checker status
Public on purpose. A site whose whole claim is "the server checks it" should say plainly which checkers are live, so you can tell the difference between not proved and we could not run the prover today.
| Isolation — required before any submission runs | available |
| Lean 4 + Mathlib — the only tool that can set ∎ | available |
| SageMath | available |
| PARI/GP | available |
| Z3 / SMT | available |