Siemens Abruptly Takes Down OpenRadioss, But a Fork is Already Live

The globally recognized tech and engineering company has quietly shut down the OpenRadioss project at the start of this month, keeping the GitHub page around but completely removing the repository.

I sound complainy because usually when an open project is discontinued, the maintainers put it into a read-only, public archive state, which allows other developers to learn and fork off it.

OpenRadioss was the open source release of Radioss, a finite element solver Altair Engineering developed for crash testing, blast response, impact analysis, and other structure loading scenarios.

They had released it in September 2022, drawing in a multinational community of researchers, software developers, and industry contributors who extended the solver and built upon the code.

Siemens, which acquired Altair last year, kept the repo and its contents publicly available for more than a year after the acquisition before abruptly deleting it and redirecting people to its transition page for Simcenter Radioss.

A fork appears

Brian Clemens, the co-founder of Rocky Linux has already got an OpenRadioss fork up and running, which carries the full OpenRadioss commit history, ships under the same GNU AGPLv3 license, and is hosted on GitHub.

It's called OpenCourant, named after mathematician Richard Courant and the Courant-Friedrichs-Lewy (CFL) condition, a stability criterion central to solvers like this one.

In fact, this fork owes its existence to the AGPL. You see, Siemens is legally within its rights to take down the repository, but the license applying to every commit gave anyone the right to fork, distribute, and build on the code.

It's just sad to see how abruptly the takedown was carried out; makes you think they didn't want people to get a heads-up.

Also worth noting is that OpenCourant is an independent community project, and it is actively looking for past OpenRadioss contributors to pitch in.

What's already shipping?

Initially, the upstream build pipeline that depended on proprietary Siemens infrastructure could not be transferred. That was rebuilt from scratch, and the results appear promising.

Just days since its inception, the project is already distributing Linux and Windows x86_64 packages.

And before that, a closed-source hm_reader input-reader binary that was never committed to the git history disappeared along with the upstream OpenRadioss repository.

Thankfully, an unnamed community member who had kept a copy came forward, the OpenCourant team independently verified it, and it now ships in every build. Though they are still looking for specific release archives to start work on ARM64 support and improve current platform compatibility.

If you are interested in OpenCourant, then its package options include the Starter and Engine offerings in single and double precision, SMP builds, and converters for animation files and time history data.

You can download the latest builds from the official downloads page.

If you get lost, the INSTALL.md file can be a good resource, though keep in mind it is still the OpenRadioss version, as the OpenCourant team has yet to update it to reflect the new project.