v2026.1.1

This release makes allocation use adaptive timestepping by default, just like the physical layer.
That means users run into infeasible optimization problems less.
We also added support for multiple inflow links for UserDemand, so it can tap directly from multiple sources.
Besides that the Python package saw some performance improvements, and we squashed several bugs.

Added

• Support multiple inflow links for UserDemand. #3035
• Adaptive timestepping for allocation. #3026
• Add numerical documentation. #2994

Changed

• Improve order of tracers in plot/legend. #3052
• Python: Speed up validation. #3036
• Python: Speed up add API. #3015
• Delwaq: Change system timer and verbosity control. #3032
• run_delwaq: show stdout like run_ribasim. #3027

Fixed

• Fix allocation infeasibility reporting for some constraints. #3078
• QGIS: More robust run cancellation. #3077
• Delwaq: Remove boundary-boundary connections. #3063
• Fix starttime < endtime validation. #3059
• Fix wrongly reported intra-Junction flows. #3054
• Fix allocation bug with allocation-controlled and flow demand node IDs. #3044
• Filter missing data out of NetCDF. #3033

All changes

What's Changed

• Update installation docs for v2026.1.0 by @visr in #3013
• Update hatch version by @visr in #3010
• QGIS: Remove supportsQt6 from metadata.txt by @visr in #3011
• Update Julia manifest by @evetion in #3016
• Improve PID control setup in examples and adjust integral coefficient… by @verheem in #3017
• Update pixi lockfile by @evetion in #3018
• Bump prefix-dev/setup-pixi from 0.9.4 to 0.9.5 by @dependabot[bot] in #3020
• fix hallucinated Common Infeasibility Causes by @verheem in #3024
• Update for xmipy v1.5 error message by @visr in #3025
• Switch Python type checker from Mypy to Pyrefly by @visr in #3019
• run_delwaq: show stdout like run_ribasim by @visr in #3027
• Remove du_buff workaround, use get_du again by @verheem in #3021
• add numerical documentation by @verheem in #2994
• [Python] Speed up add API. by @evetion in #3015
• Fix display of Model. by @evetion in #3030
• [Delwaq] Change system timer, and verbosity control. by @evetion in #3032
• [Python] Speed up validation by @evetion in #3036
• Filter missing data out of NetCDF by @visr in #3033
• Fix integration test by @visr in #3038
• Fix node validation coverage by @visr in #3047
• fix bug in allocation meuse model by @verheem in #3044
• Switch back to SQLite fork by @visr in #3051
• Fix wrongly reported intra-Junction flows by @visr in #3054
• Improve GitHub Actions secure usage by @visr in #3055
• Update prek hooks by @evetion in #3057
• Update pixi lockfile by @evetion in #3056
• restore regression tests PID control by @verheem in #3058
• Bump julia-actions/cache from 3.0.2 to 3.1.0 in the all-actions group by @dependabot[bot] in #3061
• [delwaq] Remove boundary-boundary connections. by @evetion in #3063
• Upload MSIX with release assets by @visr in #3060
• Fix starttime < endtime validation by @visr in #3059
• Adaptive timestepping for allocation by @verheem in #3026
• Override QGIS task cancel by @visr in #3077
• Improve order of tracers in plot/legend by @evetion in #3052
• guard for infeasible constraints coming from the solver which have no constaint ref by @verheem in #3078
• Support UserDemand with multiple inflow links by @verheem in #3035

Full Changelog: v2026.1.0...v2026.1.1