European Environment for Scientific Software Installations (EESSI)

EESSI featured on Discovered by Compute podcast

Kenneth Hoste — Thu, 08 Oct 2026 15:22:49 +0000

EESSI featured on Discovered by Compute podcast

An interview on EESSI, as well as the impact of AI on the development and maintainers of open source sof...

Why you should vote for EESSI (again)

Kenneth Hoste — Mon, 28 Sep 2026 12:30:49 +0000

Why you should vote for EESSI (again)

At the Supercomputing 2024 conference EESSI won an HPCWire Readers' Choice Award.

On 14 September 2026, EESSI got nominated again for the HPCWire Readers' Choice Award.

We have not been sitting still, EESSI has continued to evolve significantly since late 2024.

In this blog post we take a look at the progress that has been made, highlighting some of the recent developments, enhancements, and milestones.

Read on to see what has changed in EESSI since November 2024, and why we think that EESSI deserves your vote more than ever before... :smiling_face_with_3_hearts:

EESSI nominated (again) for HPCwire Readers’ Choice Awards

Kenneth Hoste — Sun, 20 Sep 2026 12:53:33 +0000

EESSI nominated (again) for HPCwire Readers’ Choice Awards

![HPCwire Readers' Choice Awards 2026](hpcwire-readers-choice-awards-2026.webp){width=50%}

EESSI has been nominated (again) for the HPCwire Readers’ Choice Awards, in the "Best HPC Programming Tool or Technology" category.

You can help us win the award by joining the vote.

Testing MattX with EESSI

Kris Buytaert — Tue, 08 Sep 2026 08:51:15 +0000

Testing MattX with EESSI

Almost 2 decades ago openMosix was the hottest open source Single System Image (SSI) cluster out there. OpenMosix could migrate long running processes across a cluster and thus effectively allowing HPC workloads to be spread across a cluster or migrated to a node with more resources, with no changes to the code. The project however never got a 2.6 kernel port and thus was EOL by early 2008.

Earlier this year Matt Rechenburg, one of the original openMosix community members released MattX, the Modern SSI Cluster , which brought back the openMosix vibes. MattX lacked a test suite and thus I had a suite build. Initially the Mattx Test suite just spun up a number of VM's and migrated basic processes around to validate the new releases. Working on that Test suite I wondered if it weren't a good idea to take let some real HPC workloads migrate around, and where better to find them than in the EESSI demo project.

Portable test run of ESPResSo on EuroHPC systems via EESSI

Kenneth Hoste — Mon, 07 Sep 2026 11:14:22 +0000

Portable test run of ESPResSo on EuroHPC systems via EESSI

![ESPResSo logo](espresso.png){width=30%}

Since 14 June 2024, ESPResSo v4.2.2 is available in the EESSI production repository software.eessi.io, optimized for the 8 CPU targets that are fully supported by version 2023.06 of EESSI. This allows running ESPResSo effortlessly on the EuroHPC systems where EESSI is already available, like Vega and Karolina.

On 27 June 2024, an additional installation of ESPResSo v4.2.2 that is optimized for Arm A64FX processors was added, which enables also running ESPResSo efficiently on Deucalion, even though EESSI is not available yet system-wide on Deucalion (see below for more details).

With the portable test for ESPResSo that is available in the EESSI test suite we can easily evaluate the scalability of ESPResSo across EuroHPC systems, even if those systems have different system architectures.

Update on EESSI in EuroHPC Federation Platform

Kenneth Hoste — Mon, 07 Sep 2026 10:38:04 +0000

Update on EESSI in EuroHPC Federation Platform

Since our blog post in Feb'25 announcing that EESSI will be integrated in the EuroHPC Federation Platform (EFP), we have been working hard on making this a reality.

![EFP Federated Software Catalog](EFP-FSC-202602.webp){width=70%}

The Federated Software Catalog (FSC) component of EFP will use EESSI as a base. As a result, EESSI will soon be available on all EuroHPC supercomputers.

In fact, EESSI is already available on the majority of them today!

EuroHPC User Day (22-23 Oct 2024, Amsterdam)

Kenneth Hoste — Mon, 07 Sep 2026 10:22:55 +0000

EuroHPC User Day (22-23 Oct 2024, Amsterdam)

![EuroHPC User Day 2024](eurohpc_user_day_2024.webp){width=30%}

We had a great time at the EuroHPC User Day 2024 in Amsterdam earlier this week.

Both MultiXscale and EESSI were strongly represented, and the work we have been doing was clearly being appreciated.

Chasing a NaN: correct RVV HPL on a RISC-V SpaceMiT X60, through EESSI

Hugo Meiland — Sun, 12 Jul 2026 05:24:27 +0000

Chasing a NaN: correct RVV HPL on a RISC-V SpaceMiT X60, through EESSI

A fresh-install, end-to-end walkthrough on an Orange Pi RV2: reproduce a silent NaN failure in the stock EESSI HPL, trace it to one RISC-V vector kernel, and fix it — correct results — with a single eb --from-pr.

EESSI activities at ISC'26

Kenneth Hoste — Mon, 06 Jul 2026 14:45:03 +0000

EESSI activities at ISC'26

During the week of 22-26 June 2026, EESSI was part of the official program of the ISC'26 conference in Hamburg (Germany) in various ways.

Next to the Introduction to EESSI half-day tutorial and a Birds-of-a-Feather (BoF) session we organized ourselves, EESSI was also featured prominently in two other BoF sessions, including the one on the EuroHPC Federation Platform.

![](isc26-EESSI-tutorial-sign.webp){width=25%} ![](isc26-EESSI-tutorial-room.webp){width=25%} ![](isc26-BoF-01.webp){width=25%} ![](isc26-BoF-02.webp){width=25%}

In addition, we gave presentations in two workshops, witnessed how EESSI got mentioned by speakers in other sessions, and had lots of interesting discussions with members of the HPC community at the ISC exhibit or when bumping into people in the hallway track.

MPI at Warp Speed: EESSI Meets Slingshot-11

Richard Topouchian — Fri, 05 Jun 2026 13:49:20 +0000

MPI at Warp Speed: EESSI Meets Slingshot-11

High-performance computing environments are constantly evolving, and keeping pace with the latest interconnect technologies is crucial for maximising application performance. However, we cannot rebuild all the software in EESSI that depends on improvements to communication libraries. So how do we take advantage of new technological developments?

Specifically we look at taking benefit of the HPE/Cray Slingshot-11. Slingshot-11 promises to offer a significant advancement in HPC networking, offering improved bandwidth, lower latency, and better scalability for exascale computing workloads ... so this should be worth the effort!

In this blog post, we present the requirements for building OpenMPI 5.x with Slingshot-11 support on HPE/Cray systems and its integration with EESSI using the host_injections mechanism of EESSI to inject custom-built OpenMPI libraries. This approach enables overriding EESSI’s default MPI library with an ABI-compatible, Slingshot-optimized version which should give us optimal performance.

MPI at Warp Speed: EESSI Meets Slingshot-11(bis)

Richard Topouchian — Fri, 05 Jun 2026 13:49:20 +0000

MPI at Warp Speed: EESSI Meets Slingshot-11_^(bis)

Building on our initial HPE/Cray Slingshot‑11 results, we further refined MPI tuning and validated the setup using EESSI 2025.06.

The outcome is a significant performance improvement, bringing MPI support in EESSI much closer to vendor tuned Cray MPI environments.

lfoss/2025b now available in the EESSI RISC-V stack

Julián Morillo — Wed, 13 May 2026 07:39:51 +0000

`lfoss/2025b` now available in the EESSI RISC-V stack

The EESSI RISC-V software stack available through the dev.eessi.io/riscv repository now includes the lfoss/2025b toolchain.

This is an important milestone for the RISC-V enablement work in EESSI, since it brings a modern LLVM-based software toolchain to the growing collection of software available for RISC-V systems through EESSI.

Choosing EESSI as a base for MUSICA

Adam McCartney — Thu, 02 Apr 2026 18:28:09 +0000

Choosing EESSI as a base for MUSICA

![MUSICA](MUSICA-v2-32-Matthias_Heisler.jpg){width=75%}

MUSICA (Multi-Site Computer Austria) is the latest addition to Austria's national supercomputing infrastructure. The system's compute resources are distributed across three locations in Austria: Vienna, Innsbruck, and Linz. We describe the process that led to the adoption of EESSI as a base for the software stack on the MUSICA system at the Austrian Scientific Computing (ASC) research center.

Easy EESSI at EMBL

Renato Alves — Tue, 17 Feb 2026 18:23:42 +0000

Easy EESSI at EMBL

Experiences from EMBL's CoDash hackathon on EESSI

Bringing EESSI and EMBL's computational community closer together during EMBL's CoDash hackathon. Simultaneously working towards bringing a large repository of scientific software in-use at EMBL's HPC cluster to EESSI.

Using Spack on top of EESSI: A Proof of Concept

Loris Ercole — Mon, 09 Feb 2026 14:34:51 +0000

Using Spack on top of EESSI: A Proof of Concept

![Spack + EESSI](spack-plus-eessi.webp){width=75%}

EESSI provides a rich set of software installations, which were built and installed using EasyBuild.

Can we convince Spack to reuse software installed in EESSI, and by doing so make EESSI more attractive to those of you who prefer using Spack over EasyBuild?

Several people have expressed interest in exposing the software installations provided by EESSI to Spack, so they can be used as dependencies when building and installing software with Spack.

Recently, we have explored how this could be achieved through a proof-of-concept with QuantumESPRESSO.

The goal here is to build and install only QuantumESPRESSO with Spack, and leveraging software installations from EESSI for all required dependencies, including the compiler and libraries for MPI, BLAS/LAPACK, FFTW, etc.

Using Spack on Top of EESSI: Best of Both Worlds

Loris Ercole — Mon, 09 Feb 2026 14:34:51 +0000

Using Spack on Top of EESSI: Best of Both Worlds

![Spack + EESSI](../01/spack-plus-eessi.webp){width=75%}

The HPC software landscape offers powerful tools for managing scientific software, such as EasyBuild and Spack.

EESSI provides a ready-to-use software stack with thousands of optimized software installations that were built with EasyBuild.

Imagine you are working on an HPC system with EESSI already available. You have access to a wealth of optimized installations for scientific software packages, libraries, tools, as well as compilers. But you need to install a new tool or a specific version of a package that's not in EESSI yet.

You can already extend EESSI with new software through the EESSI-extend module. This utility provides you with a pre-configured EasyBuild installation that you can use to build packages from easyconfig files.

Like EasyBuild, Spack is a flexible build tool that also offers a vast repository of build recipes maintained by a large and active community, making it a familiar tool for many HPC users. By enabling Spack to leverage software installations already available in EESSI as dependencies, we can offer users the best of both worlds: the convenience of a pre-built, optimized software stack combined with the flexibility to quickly build new packages using tools they already know.

EESSI at FOSDEM'26

Helena Vela Beltran — Wed, 04 Feb 2026 21:43:16 +0000

EESSI at FOSDEM'26

This year's FOSDEM exceeded all expectations a first-time attendee like me could have. Filled with interesting talks, wide range of diverse people and impactful projects, I bring back home a bag full of stickers, lovely memories and some Belgian chocolates.

![Stickers](stickers.webp){width=70%}

GitHub CI/CD workflows with EESSI

Jean-Noël Grad — Wed, 04 Feb 2026 20:31:23 +0000

GitHub CI/CD workflows with EESSI

In a previous blog post, “An example CI workflow that leverages EESSI CI tools”, Pedro Santos Neves explained how to set up a GitLab CI workflow. This post will focus on GitHub CI workflows and show how to access the development repository of EESSI.

EuroHPC User Days 2025 + CI/CD Hackathon

Kenneth Hoste — Sun, 11 Jan 2026 10:10:09 +0000

EuroHPC User Days 2025 + CI/CD Hackathon

![EuroHPC User Days 2025](eurohpc-user-days-2025.webp){width=50%}

The [EuroHP...

EESSI on Kubernetes: A Proof of Concept

Davide Grassano — Mon, 08 Dec 2025 11:56:55 +0000

EESSI on Kubernetes: A Proof of Concept

Kubernetes, also known as K8s, is an open-source container orchestration platform widely used for automating the deployment, scaling, and management of containerized applications. Normally, deploying a specific application on Kubernetes requires preparing a container image including the target software and all its dependencies. Furthermore, the software should be optimized depending on the target hardware architecture to achieve the best performance, which could prove particularly challenging especially on heterogeneous systems. Implementing an integration of EESSI with Kubernetes will allow the many sites and enterprises that already use K8s to more easily get access to a wide variety of optimized software installations.

In this blog post, we present a proof of concept (PoC) for deploying EESSI on a Kubernetes cluster.