  This paper presents an open-source toolbox, MMRec for multimodal
recommendation. MMRec simplifies and canonicalizes the process of implementing
and comparing multimodal recommendation models. The objective of MMRec is to
provide a unified and configurable arena that can minimize the effort in
implementing and testing multimodal recommendation models. It enables
multimodal models, ranging from traditional matrix factorization to modern
graph-based algorithms, capable of fusing information from multiple modalities
simultaneously. Our documentation, examples, and source code are available at
\url{https://github.com/enoche/MMRec}.
