The goal is to help studying logic and solvers by providing easy-to-use, pure browser-based javascript tools for both full classical predicate logic and propositional formulas at the logictools.org site.
The high-performance predicate logic prover gkc is written in C and available available under the AGPL v3 licence as a command line tool on Linux, Windows and macOS and Wasm for running in the browser. The browser version on this site is inevitably crippled when compared to the command-line version: the latter can utilize multiple cores, all the available memory, shared memory databases and has several additional options not available in the browser. The browser version runs on a single core and has severe memory restrictions.
The educational propositional provers are self-contained, no-dependencies, easy-to-hack javascript code under the MIT licence. The focus is on simplicity, ease of use, hacking and experimenting, not state of the art efficiency-wise.
Contact the author Tanel Tammet as (tanel.tammet at gmail.com).