A curated list of open source projects used in nuclear science and engineering.

• BART — Finite-element, discrete ordinates code developed by UC-Berkeley
• Dragon — Lattice code developed by Polytechnique Montreal
• FRENSIE — Monte Carlo neutron/photon transport code
• Geant4 — High-energy Monte Carlo particle transport code
• OpenMC — Monte Carlo neutron/photon transport code
• OpenMOC — Method of characteristics code
• Warp — Monte Carlo neutron transport code on GPUs

• ACE Format — Documentation of the ACE format
• csg2csg — Tool to translate between different CSG types
• DAGMC — Direct accelerated geometry Monte Carlo toolkit
• serpent-tools — Python-based tool suite for Serpent

• EMPIRE — Nuclear reaction model code
• FRENDY — Nuclear data processing
• FUDGE — Python-based nuclear data processing
• NJOY21 — Nuclear data processing
• PREPRO — Nuclear data processing
• SANDY — Sampling tool for nuclear data
• PyNjoy 2012 — Nuclear data processing

• ALARA — Activation code widely used for fusion
• ONIX — Python-based burnup code

• ADPRES — Neutron diffusion equation based nuclear reactor simulator and core analysis tool
• PyRK — Neutronic and thermal hydraulic reactor transient analysis in 0-D

• Cyclus — Nuclear fuel cycle simulator

• Nek5000 — Spectral-element CFD code
• nekRS — Spectral-element CFD code targeting modern processors and accelerators
• OpenFOAM — Finite volume CFD code

• ENRICO — Monte Carlo + CFD coupling application
• MOOSE — Finite-element, multiphysics framework
• Okapi — OpenMC wrapped as a MOOSE app
• SALOME — Interoperability between CAD and multiphysics software

• Moltres — A molten salt reactor simulator code

• PyNE — Python/C++ nuclear engineering toolkit
• ARMI — Reactor analysis automation framework
• LaTeX classes and BibTeX style for ANS publications

• ARFC (UIUC) — Advanced Reactors and Fuel Cycles
• CNERG (UW-Madison) — Computational Nuclear Engineering Research Group
• CRPG (MIT) — Computational Reactor Physics Group