Migration Guide

principle-econ was renamed to principle-viz and joined the EconViz family alongside utility-viz.

No compatibility layer

principle-econ stops receiving updates after v0.1.0, and there is no principle_econ shim in principle-viz. Update your imports and commands when you switch.

What changed

	principle-econ	principle-viz
Distribution	`uv add principle-econ`	`uv add principle-viz`
Import	`import principle_econ`	`import principle_viz`
CLI	`principle-econ`	`principle-viz`

Switch packages

uv remove principle-econ
uv add principle-viz

Then replace the package name in your code and scripts:

principle_econ becomes principle_viz in every import.
principle-econ becomes principle-viz in shell scripts and CI.

Module layout is unchanged

Sub-packages such as core, policy, welfare, plot, api and cli keep their names, so principle_econ.core.line is now principle_viz.core.line.

Behavior changes since 0.1.0

Upgrading from principle-econ 0.1.0 also brings the figure changes made up to v0.10.0.

Area	Change
Legend	`MarketFigure.finalize()` no longer adds a legend. Pass `finalize(legend=True)` to keep the old behavior
Welfare labels	Regions are named ("Consumer surplus", "DWL", ...) instead of lettered `A/B/C/D`
`LabeledRegion`	Carries `key`, `label` and `short_label` instead of `letter`
Curve names	Placed beside the curve end instead of only in the legend
Dependency	Requires `mosaickit>=0.5.1,<0.6.0`, installed automatically

Calculations are unchanged

Welfare and equilibrium results are the same. Only the drawing and labeling changed.

For contributors

The project switched from Poetry to uv: pyproject.toml is PEP 621 with uv_build, and uv.lock replaces poetry.lock. Use uv sync to set up, as described in Installation.