evalhyd is a software stack to evaluate deterministic and probabilistic streamflow predictions. It features a core library in C++ where all the evaluation metrics and the required functionalities are implemented. It comes with Python bindings and R bindings, as well as a Command Line Interface (CLI), all giving access through very similar interfaces to the same metrics and functionalities implemented in the C++ core. The documentation for the evalhyd stack is accessible at https://hydrogr.github.io/evalhyd/