MERRILL
Micromagnetic Earth Related Robust Interpreted Language Laboratory

Changelog

Version history and release notes for MERRILL — what changed, what was fixed, and when

Full source history and tagged releases are on Bitbucket. For download links see the Downloads page.

Current release

v1.8.6p 2024 Stable
  • Updated material parameter conventions for consistency across mineral types.
  • Improved handling of non-stoichiometric titanomagnetite compositions (Fe3-xTixO4).
  • Minor corrections to IRM/DCD protocol output formatting.
  • Pre-compiled packages refreshed for macOS (Apple Silicon + Intel), Linux, and Windows.

Download v1.8.6p →

Previous releases

v1.8.5 2023
  • Added pyrrhotite and greigite material parameter presets.
  • Nudged-elastic-band (NEB) path search stability improvements for large meshes.
  • FORC simulation output now includes field step metadata in header.
  • Fixed edge case in multi-phase assemblage energy minimisation.
v1.8.0 2022
  • Major refactor of the energy minimisation core — improved convergence for vortex-state grains.
  • New scripted FORC protocol with configurable field sweep parameters.
  • Magnetisation output now exported in VTK format for direct ParaView visualisation.
  • Windows package introduced for the first time.
v1.7.x series 2019–2021
  • Introduced scripted hysteresis and IRM/DCD measurement protocols.
  • Added support for tetrahedral meshes from Netgen/GMSH export.
  • Exchange stiffness A made configurable per simulation.
  • Multiple bug fixes to boundary condition handling in elongated grains.
v1.0 — Initial public release 2018
  • First public release of MERRILL as described in Geochemistry, Geophysics, Geosystems (Ó Conbhuí et al., 2018).
  • Core finite-element solver for 3D micromagnetics on tetrahedral meshes.
  • macOS and Linux packages only.

Coming next — MERRILL 3

MERRILL 3 is a ground-up redevelopment with a Python API, CI/CD pipeline, and expanded benchmark suite, currently planned for release in Q4 2027. See the Development Roadmap for full details.

Known limitations in v1.8.6p

  • Maximum practical mesh size is approximately 50,000 nodes on a modern workstation (memory-limited).
  • MScript does not yet support parallel multi-grain batch runs natively; shell scripting is required.
  • VTK output is limited to magnetisation vectors; stress/strain coupling is not implemented.
  • Windows packages are unsigned — users may need to grant permission on first run.
  • Apple Silicon binaries are compiled for arm64; Rosetta 2 is not required but Intel packages are also provided for compatibility.