MaxGhenis · Sep 30, 2026 · Sep 30, 2026 · Sep 30, 2026 · Sep 30, 2026 · Sep 30, 2026
diff --git a/docs/analysis/pe_us_bridge_20260930/household_a_waterfall.png b/docs/analysis/pe_us_bridge_20260930/household_a_waterfall.png
diff --git a/docs/analysis/pe_us_bridge_20260930/household_a_waterfall.svg b/docs/analysis/pe_us_bridge_20260930/household_a_waterfall.svg
diff --git a/docs/analysis/pe_us_bridge_20260930/household_b_waterfall.png b/docs/analysis/pe_us_bridge_20260930/household_b_waterfall.png
diff --git a/docs/analysis/pe_us_bridge_20260930/household_b_waterfall.svg b/docs/analysis/pe_us_bridge_20260930/household_b_waterfall.svg
diff --git a/docs/analysis/pe_us_bridge_20260930/household_c_waterfall.png b/docs/analysis/pe_us_bridge_20260930/household_c_waterfall.png
diff --git a/docs/analysis/pe_us_bridge_20260930/household_c_waterfall.svg b/docs/analysis/pe_us_bridge_20260930/household_c_waterfall.svg
diff --git a/docs/analysis/pe_us_bridge_20260930/pe_us_minimum_benefit_sample_households.json b/docs/analysis/pe_us_bridge_20260930/pe_us_minimum_benefit_sample_households.json
diff --git a/docs/analysis/pe_us_bridge_20260930/pe_us_minimum_benefit_sample_households.md b/docs/analysis/pe_us_bridge_20260930/pe_us_minimum_benefit_sample_households.md
diff --git a/docs/design/pe_us_bridge.md b/docs/design/pe_us_bridge.md
diff --git a/scripts/first_estimates_birth_evidence.py b/scripts/first_estimates_birth_evidence.py
@@ -334,6 +334,11 @@
     Path("scripts/track_u2_component_diagnostics.py"),
     Path("scripts/run_track_u2_registered.py"),
     Path("scripts/u2_u1_differential.py"),
+    # The opt-in PolicyEngine-US bridge passes benefit amounts to an
+    # external tax-benefit model after the fact; nothing historical imports
+    # it.
+    Path("src/populace_dynamics/bridge/__init__.py"),
+    Path("src/populace_dynamics/bridge/policyengine_us.py"),
 )
 POST_REVIEW_SHARED_SOURCE_BLOBS = {
     Path(

diff --git a/scripts/pe_us_minimum_benefit_sample_households.py b/scripts/pe_us_minimum_benefit_sample_households.py
diff --git a/src/populace_dynamics/bridge/__init__.py b/src/populace_dynamics/bridge/__init__.py
@@ -0,0 +1,8 @@
+"""Bridges from Microcosm Dynamics to external tax-benefit models.
+
+:mod:`populace_dynamics.bridge.policyengine_us` passes Microcosm benefit
+amounts to PolicyEngine-US as household inputs and decomposes the change
+in PolicyEngine-US's ``household_net_income``.  The package is opt-in: the
+historical projection never imports it, and it adds no dependency on
+``policyengine-us`` (that model runs in a separate interpreter).
+"""