I am also involved in software development. Most of the projects can be found on my Github profile but the following three are the ones I regularly contribute to:
- GAPT is a framework for proof theory and automated reasoning
- Vampire is an award-winning first-order theorem prover
- TLAPS is an interactive proof system for the first order temporal logic TLA+
If you are interested in Prolog and OCaml, you might want to visit my Stack Overflow profile.