McXtrace - Monte Carlo Xray Tracing, is a joint venture by

Our code is based on technology from

Code repository (shared with 'McStas') is located at github.com/mccode-dev

For information on our progress, please subscribe to our user mailinglist..

• To download the latest release: download area
• For installation instructions :
• McXtrace 3.x installation
• For a quick list of the available commands: commands

Recent McXtrace News

Migrating from McXtrace 1.x to 3.x? - Use the wiki-based guides

March 31st: First circular: PHOTONS AND NEUTRONS REALISTIC ARTIFICIAL INTELLIGENCE DATASETS (PaNRAID)

Dear Colleagues,

In collaboration with the French DIADEM Academy, we invite interested participants to attend the following course in September:

	PHOTONS AND NEUTRONS REALISTIC ARTIFICIAL INTELLIGENCE DATASETS (PaNRAID)

Dates: 21-25 September
Location: Île d’Oléron, France

Objective

The course will develop an integrated approach for generating synthetic data for supervised learning. This approach combines multi-scale materials simulations (DFT, MD, XAS spectroscopy) with comprehensive digital twins of experimental X‑ray and neutron facilities, explicitly accounting for instrumental effects and experimental artefacts.

Intended audience

• Doctoral students
• Postdoctoral researchers
• Faculty and teaching-research staff
• Researchers and research engineers

Further information and pre-registration: https://formation.pepr-diadem.fr/formation-panraid

Attached are PDF flyers in French and English.

Best regards,
Peter Willendrup

March 28th, 2026: McXtrace 1.x and McStas 2.x formally out of support

Dear all,

We have decided to formally declare that we no longer support McXtrace 1.x and McStas 2.x, so user issues with these released will from now on always prompt us to request that you upgrade.

If you are still running such an old release, please upgrade and port your comps/instruments using the information in the use the wiki-based porting-guides

We are of course at your service if you have issues porting your existing code, please create a GitHub issue.

What's Changed - Main Changes:

Bugfixes, new features, all common to McStas and McXtrace:

• macOS bundles in 3.6.1 did not actually install that version but something earlier. Fixed by pinning in yml file, @willend in #2285
• PDF manuals had wrong version numbers, @willend in #2285
• Allow mcrun / mcdisplay to run / visualize without access to .c/.instr by @willend in #2281
• mcgui/mxgui editable font colors, handle long filenames without extreme window resizing by @willend in #2275
• Fix cross-platform sort-order issue in PowderN by @willend in #2272
• Platform-independent reflection list sort in Single_crystal by @willend in #2273
• mcrun/mxrun: feature addition - scan by seed by @willend in #2276
• Add mcplot toggle to "plot 1D-curves from 0-value" in linear mode by @willend in #2278
• Add commentstring to vim editor by @Lomholy in #2284

Other stuff

• %Example adjustments, McXtrace by @willend in #2269
• Test_SANS/Test_SAXS, supplement stats by x10 SPLIT by @willend in #2270
• Use ${{ matrix.mpi }} to ensure different output dirs by @willend in #2271
• Fix indentation bug - issue #2279 by @willend in #2280
• Temporarily disable this instr from McXtrace tests by @willend in #2283

Full Changelog:https://github.com/mccode-dev/McCode/compare/v3.6.1...v3.6.5