GROMACS recently made its latest bug fix release, version 5.1.2! As part of BioExcel, GROMACS is continuing its transition to becoming a state-of-the-art C++11 library. Modularizing and simplifying the main molecular dynamics loop is a critical part of this, so that the core development team and third-party users of GROMACS libraries can re-use the infrastructure for new and exciting biomolecular simulation workflows. Several bugs potentially affecting code paths important for automated free-energy workflows were identified as part of the modularization, and have now been fixed in 5.1.2. Test cases have been constructed as part of the BioExcel commitment to professional quality assurance in our software engineering, and will ensure these issues remain fixed over the long term.

You can find the code, documentation, release notes, and test suite at the links below.

ftp://ftp.gromacs.org/pub/gromacs/gromacs-5.1.2.tar.gz
http://manual.gromacs.org/documentation/5.1.2/index.html (including installation guide, user guide, reference manual)
http://manual.gromacs.org/documentation/5.1.2/ReleaseNotes/index.html
http://gerrit.gromacs.org/download/regressiontests-5.1.2.tar.gz