Decision diagrams (DDs) are an important data structure in computer science with applications ranging from circuit design and verification to machine learning. Most prominently, binary DDs are commonly used to succinctly represent Boolean functions. Due to the practical importance of DDs, there is an ongoing quest for high-performance software libraries supporting the construction and manipulation of DDs. With OxiDD, we present a new framework for DDs that focuses on safety, concurrency, and modularity. Following a highly modular design we implement OxiDD in Rust, which facilitates the integration of various kinds of DDs such as MTBDDs, ZBDDs, and TDDs, all within safe code also in a concurrent setting. Already in its initial release, OxiDD does not compromise performance, which we show to be on par with or even better than established highly optimized DD libraries.