  MathRepo, located at https://mathrepo.mis.mpg.de, is an online repository for
mathematical research data. In mathematics, research data comes in many
different flavours. For instance, in computer algebra it most often takes the
form of mathematical documents, notebooks, research-software packages and
libraries, computer algebra systems, algorithms, and collections of
mathematical objects. In this work we give an overview of the type of
contributions hosted by MathRepo, we discuss the principles that should be
followed to make a research-data repository good, and the current challenges we
are facing as MathRepo's maintainers.
