GRBoondi: A code for evolving Generalized Proca theories on arbitrary backgrounds

While numerical simulations offer unparalleled precision and robustness in studying complex phys- ical systems, their execution is often hindered by complexity, costliness, and time consumption due to the intricate equations involved. This challenge is already encountered in General Relativity, where non-flat spacetimes exacerbate the computational burden. This complexity is further in- tensified when dealing with additional degrees of freedom. To address this challenge head-on, we introduce GRBoondi , a groundbreaking fixed-background numerical relativity code designed to pro- vide a unified interface for numerically solving Generalized Proca theories. GRBoondi grants users the ability to make arbitrary modifications to the Proca equations of motion on any background, providing a robust and versatile tool for exploring diverse classes of Generalized Proca theories. This letter serves as part of the submission of GRBoondi to the Journal of Open Source Software. For access to the code, please visit https://github.com/ShaunFell/GRBoondi.git