Open-source software is a prerequisite for safe civil nuclear energy.

Nuclear power is one of the most consequential technologies humanity has ever built. The software that models, simulates, and governs its operation should be open, peer-reviewed, and accessible — not locked behind institutional walls or proprietary licenses.

We believe that the future of civilian nuclear is built on transparent tools. When engineers everywhere can inspect, extend, and improve the simulation codes underlying reactor design and safety analysis, we raise the floor for the entire field. Obscure software is a liability. Open software is infrastructure.

This is not a niche concern. As the world debates nuclear's role in a decarbonised energy system, the communities capable of building and certifying new designs must have access to the same quality tools — regardless of geography, institution, or budget.

A curated index of nuclear open-source tools is maintained at awesome-nuclear. Computational fluid dynamics codes relevant to nuclear thermal-hydraulics are collected at Code4CFD. For coupled multiphysics simulation of nuclear systems, see foam-for-Nuclear.

These projects exist. They work.