Meta AI Open-Sources Rebalancer: A C++ Assignment Solver That Runs About 40 Million Placement Problems a Day

Meta has open-sourced Rebalancer, a C++ and Python library used internally for over nine years to solve approximately 40 million assignment problems daily, supporting local search and MIP solvers such as Gurobi, FICO Xpress, and HiGHS. The library is available under Apache 2.0 and can be installed via pip.