# First GROMACS 2021 release candidate **URL:** \ **Category:** Announcements\ **Created:** [December 30, 2020, 4:44pm UTC](https://gromacs.bioexcel.eu/t/first-gromacs-2021-release-candidate/1357 "2020-12-30T16:44:30Z")\ **Posts on this page:** 4\ **Page:** 1
**Author:** ![pszilard](https://dub1.discourse-cdn.com/flex017/user_avatar/gromacs.bioexcel.eu/pszilard/32/21_2.png) [@pszilard](https://gromacs.bioexcel.eu/u/pszilard)\ **Post date:** [December 30, 2020, 4:44pm UTC](https://gromacs.bioexcel.eu/t/first-gromacs-2021-release-candidate/1357/1 "2020-12-30T16:44:30Z")
Hi GROMACS users, Thanks to all of you who tested the GROMACS 2021 beta releases! We have improved a couple of things based on the feedback to the beta releases and are proud to announce the first release candidate of GROMACS 2021! We are making this available to you to get an early taste of how GROMACS 2021 will look and work, and most importantly to get feedback from you about how well things work. While we try our hardest to keep the quality of GROMACS as high as possible, we’re human, we overlook things while doing other things, and we need your many pairs of eyes to help build a tool that we can all use to do good science! We really need you to test your kinds of simulation on your hardware, both for correctness and performance. This is particularly important if you are using “interesting” hardware or compilers, because we can’t test all of them! Please do not use this version for doing science you plan to publish - it needs more testing before it’s reliable enough for that. Similarly, please don’t use this version as a base for a project that bundles or forks GROMACS. What new things can you expect? (See the release notes for more details.) - Free energy perturbation with AWH - Support for ARM SVE - Multiple time stepping simulations - Stochastic rescaling barostat for equilibration and production - PME offloading to GPUs also for free energy simulations - API for nonbonded interactions with NB-LIB There are lots of other new things, and a few old things removed - please see the release notes for the complete list. All the content of GROMACS 2020.4 is present, apart from features that have been removed. Your testing helps us harden the final release. To follow progress and give further feedback have a look at the [2021 milestone on gitlab](https://gitlab.com/gromacs/gromacs/-/milestones/94) and [report issues there](https://gitlab.com/gromacs/gromacs/-/issues). If all goes to plan, we hope to ship the final 2021 release in the middle of January next year, but that relies on people joining in and helping us test! We hope you will consider making that contribution, so that we can continue to deliver high-quality free simulation software that will be useful to you. Find the code, manual, release notes, installation instructions and testsuite at the links below. Code: ftp://ftp.gromacs.org/pub/gromacs/gromacs-2021-rc1.tar.gz Documentation: [http://manual.gromacs.org/documentation/2021-rc1/index.html](http://manual.gromacs.org/documentation/2021-rc1/index.html) (includes install guide, user guide, reference manual) Release Notes: [http://manual.gromacs.org/documentation/2021-rc1/release-notes/index.html](http://manual.gromacs.org/documentation/2021-rc1/release-notes/index.html) Test Suite: ftp://ftp.gromacs.org/pub/regressiontests/regressiontests-2021-rc1.tar.gz Happy testing! Szilárd ---
**Author:** ![pszilard](https://dub1.discourse-cdn.com/flex017/user_avatar/gromacs.bioexcel.eu/pszilard/32/21_2.png) [@pszilard](https://gromacs.bioexcel.eu/u/pszilard)\ **Post date:** [December 30, 2020, 7:46pm UTC](https://gromacs.bioexcel.eu/t/first-gromacs-2021-release-candidate/1357/2 "2020-12-30T19:46:44Z")
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**Author:** ![avilla](https://avatars.discourse-cdn.com/v4/letter/a/f1d935/32.png) [@avilla](https://gromacs.bioexcel.eu/u/avilla)\ **Post date:** [December 31, 2020, 4:56pm UTC](https://gromacs.bioexcel.eu/t/first-gromacs-2021-release-candidate/1357/3 "2020-12-31T16:56:15Z")
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**Author:** ![avilla](https://avatars.discourse-cdn.com/v4/letter/a/f1d935/32.png) [@avilla](https://gromacs.bioexcel.eu/u/avilla)\ **Post date:** [January 28, 2021, 3:23pm UTC](https://gromacs.bioexcel.eu/t/first-gromacs-2021-release-candidate/1357/4 "2021-01-28T15:23:22Z")