Software
The Sequent Calculus Trainer is a tool that aims at supporting students in learning how to correctly construct proofs in the sequent calculus for propositional logic and first-order logic with equality.
The PGSolver library is a collection of algorithms for solving parity games that appear somewhere in the literature, as well as some new heuristics etc. It also defines a standard specification format for parity games as well as winning regions and strategies, and provides a collection of benchmark games. Co-developer of this tool is Oliver Friedmann.