GROMACS Developments

The GROMACS 2025 series is being released this year: version 2025.0 was released on the 11^th of February 2025, 2025.1 in March, and 2025.2 in May (see manual.gromacs.org/2025.2/release-notes/2025/major/highlights.html ).

GROMACS 2025 is mainly characterised by the inclusion of a (limited) interface to the PLUMED package ( www.plumed.org ), more support for hydrodynamics simulations and for force-field forms including neural-network potentials, plus improvements in performance.

A PLUMED interface using the MDModules interface is being shipped with GROMACS. This functions in a similar way to the Colvars interface that was implemented for GROMACS in 2024. Now it is only necessary to link GROMACS with PLUMED; special code hacking is no longer required! This guarantees that PLUMED sees an up-to-date state with integration on GPU. Note that the PLUMED interface is currently limited to certain features at present, whereas the entire Colvars package is included in GROMACS. Also neural network potentials are implemented via an interface, in this case with PyTorch. More specifically, PyTorch is used to train the model, then the trained model is exported and the coordinates are fed into GROMACS via TorchScript and the PyTorch C++ API. Currently, neural network potential/ molecular mechanics (NNP/MM) simulations using mechanical embedding schemes are also possible.

GROMACS’ recent performance improvements include automatically turning on more GPU features, an initial version of a HIP backend that targets AMD GPUs and more OpenMP parallelisation, plus GPU-direct communication is now used by default when the MPI library supports it. In addition, enhanced particle-particle (PP) halo exchange using GPU kernel-initiated communication has been implemented using NVSHMEM, thereby improving performance when scaling to multiple NVIDIA GPUs.

Moreover, GROMACS 2025 has the option to have different CMAP types for each amino acid, which will make it possible to use the most current Amber protein force field (that is, ff19SB) soon. Also, there is support for volume scaling of centres of mass of more than one position restraint group, which has enabled shear with walls and constant pressure in 2025.

Now the developers are working to bring new features into the 2026 release. You can follow the development of GROMACS by looking at the GROMACS GitLab repository ( gitlab.com/gromacs ) or at the developer discussions section of the GROMACS discussion forum ( forums.gromacs.org ). Finally, GROMACS developer calls are held every second Wednesday (alternating between 11:00 and 17:00 CET/CEST) and everybody is welcome to join these calls. Information about how to join the calls is posted on the forums.

As always, if you need some help with your simulations, you are welcome to sign up in the user discussion section of the GROMACS user forum (which can be found at forums.gromacs.org ) and ask your questions there. You can also keep yourself updated by following the latest GROMACS news on www.gromacs.org .

To find out more about GROMACS 2025, you can watch the “What’s new in GROMACS 2025” webinar (see bioexcel.eu/webinar-whats-new-in-gromacs-2025-2025-2-18 ).

If you are interested in attending the next “Learn to Code in GROMACS” workshop, keep an eye on bioexcel.eu/events  for announcements.