  We present divERGe, an open source, high-performance C/C++/Python library for
functional renormalization group (FRG) calculations on lattice fermions. The
versatile model interface is tailored to real materials applications and
seamlessly integrates with existing, standard tools from the ab-initio
community. The code fully supports multi-site, multi-orbital, and non-SU(2)
models in all of the three included FRG variants: TU$^2$FRG, N-patch FRG, and
grid FRG. With this, the divERGe library paves the way for widespread
application of FRG as a tool in the study of competing orders in quantum
materials.
