Cyclus 1.3 Release Notes

Author:Cyclus Developers

The Cyclus core team is excited to announce the latest stable version of the cyclus ecosystem!

Major features


  • ~3x speedups for recipe-based simulations
  • Basic inventory policies added
  • Support for recursive containers in archetypes
  • Many new recursive containers added to sqlite backend
  • Regression tests run on macs!
  • A MockSim interface for full simulation testing without input files
  • Added customizeable TimeSeries output for recording archetype-specific time series
  • Added json-to-xml conversion capability
  • Added new ResMap container
  • Decay added (via Pyne)! An input file flag can be set to
    • never: never decay
    • manual: archetypes must call the decay API manually
    • lazy: materials are decayed as needed when their Material::comp function is called


  • New facility archetypes added
    • Reactor
    • FuelFab
    • Separations
    • Enrichment
  • Other facility archetypes removed
    • BatchReactor
    • EnrichmentFacility
  • Some experimental archetype APIs updated
    • GrowthRegion
  • Much better end-of-life fuel handling in reactors
  • Regression tests run on macs!


  • First release for a new analysis and visualization tool for Cyclus simulation output
  • Command line tool and Python interface
  • Calculates metrics of user interest from a Cyclus database
    • Writes metrics back to database
    • Simple for users to extend the suite of metrics
      • Designed so calculations can be based on dependencies (other metrics or root metrics)
      • Uses pandas data types
    • Uses PyNE for nuclear data
  • Visualization available from the command line via matplotlib


Since v1.2.0,

  • Cyclus: 409 commits resulting in 113 files changed, 8466 insertions(+), 1760 deletions(-)
  • Cycamore: 353 commits resulting in 79 files changed, 7466 insertions(+), 6830 deletions(-)
  • Cymetric: 366 commits resulting in 49 files changed, 5978 insertions(+), 266 deletions(-)


The following people contributed to this release of Cyclus. A “*” by their name indicates a first time contributor. Names follow alphabetically,

  • Robert Carlsen
  • Denia Djokic*
  • Robert Flanagan
  • Matthew Gidden
  • Katy Huff
  • Meghan McGarry*
  • Arrielle Opotowsky
  • Olzhas Rakhimov
  • Anthony Scopatz
  • Paul Wilson
  • John Xia