Update PolicyEngine Core

MaxGhenis · MaxGhenis · commit 40f1802a688e · 2026-06-04T12:32:52.000Z
diff --git a/CHANGELOG.md b/CHANGELOG.md
@@ -1,3 +1,10 @@
+## [3.27.0] - 2026-06-04
+
+### Added
+
+- Forbid random number generation inside variable formulas. A rules-engine formula must be a pure, deterministic function of its inputs, so any call to `numpy.random` or the standard library `random` module while a formula runs now raises `NonDeterministicFormulaError`. Stochastic inputs must be precomputed deterministically when building the dataset. Removes the per-variable `np.random.seed` previously applied before each calculation, which existed only to make formula-level randomness reproducible.
+
+
 ## [3.26.11] - 2026-05-21
 
 ### Fixed
diff --git a/changelog.d/forbid-randomness-in-formulas.added.md b/changelog.d/forbid-randomness-in-formulas.added.md
diff --git a/pyproject.toml b/pyproject.toml
@@ -1,6 +1,6 @@
 [project]
 name = "policyengine-core"
-version = "3.26.11"
+version = "3.27.0"
 description = "Core microsimulation engine enabling country-specific policy models."
 readme = "README.md"
 authors = [
