Following the growing interest that we observe in the use of OpenFOAM for nuclear reactor analysis, the current work presents a point-kinetics model and associated open-source code that can easily be integrated in existing thermal–hydraulic solvers to streamline the use of OpenFOAM for multi-physics investigations. As a proof of concept, we have integrated the new solver in the GeN-Foam multiphysics platform, and validated it against past experimental measurements from the Fast Flux Test Facility, a 400 MW (th) Sodium-cooled Fast Reactor located at the Hanford Site, Washington, USA. Both steady-state and transient simulations provide satisfactory results, also in view of previous studies with other codes. Overall, the developed point-kinetics model and its integration in GeN-Foam have proven to be suitable for the system-level investigation of nuclear reactor transients, thus enabling a more widespread use by the nuclear community of a major open-source toolkit like OpenFOAM.