Here are some (randomly selected) projects I am currently working on or contributing to. For a full overview, see my GitHub page.
A tool that generates GAP documentation from source code and doxygen style comments.
A GAP package for category theory. It facilitates the implementation of specific instances of categories and provides a language for writing generic categorical algorithms. See research for more details.
A GAP project for computations in homological algebra, consisting of multiple packages along with interfaces to other CAS.
A python wrapper kernel for using the Singular CAS in Jupyter. It accesses Singular using Singulars callable library and PySingular, a wrapper for some library functions written in C++ for python 2 and 3.
A python wrapper kernel for using the polymake CAS in Jupyter. It accesses polymake using polymakes callable and JuPyMake, a wrapper for the necessary polymake callable library functions written in C++ for python 2 and 3. The Jupyter kernel is shipped with polymake.
Python 2/3 interface for the Normaliz library for convex geometry. It provides full access to all functionality of the library, along with more python-esque classes and wrappers for functions and output. It is currently used in SageMath.