Add local Marketplace impact slice

.gitignore

@@ -46,6 +46,10 @@ Thumbs.db
 
 # Data/cache
 .cache/
+!aca_calc/data/
+!aca_calc/data/*.json
+!src/data/
+!src/data/**
 # data/ is gitignored except for the stub fixtures committed for build/CI.
 data/*
 !data/households
@@ -68,4 +72,4 @@ next-env.d.ts
 .vercel
 
 # Env
-.env*.local
+.env*.local

CONTRIBUTING.md

@@ -2,43 +2,66 @@
 
 ## Code Structure
 
-### Main Application (`app.py`)
+### React Application
 
-**Key Functions:**
+The user-facing ACA calculator lives in the Next.js/React app:
 
-1. **`calculate_ptc()`** - Core calculation logic
-   - Builds household situation dictionary
-   - Applies reform parameters if requested
-   - Returns PTC and SLCSP values
-   - County format: "Travis County" → "TRAVIS_COUNTY_TX"
+- `app/`: Next.js shell
+- `src/App.jsx`: top-level application routing and tabs
+- `src/components/Calculator.jsx`: calculator orchestration
+- `src/components/CalculatorForm.jsx`: household input form
+- `src/components/CalculatorResults.jsx`: calculator outputs and charts
+- `src/views/LocalImpact.jsx`: local enrollment and premium context
 
-2. **`create_chart()`** - Visualization
-   - Generates income sweep curves
-   - Shows user's position on curves
-   - Compares baseline vs reform scenarios
+Run it locally with:
 
-3. **`main()`** - Streamlit UI
-   - Handles user inputs
-   - Displays results
-   - Manages session state
+```bash
+npm run dev
+```
+
+The calculator route is `/#calculator`.
+
+### Python Package
+
+Reusable PolicyEngine and data access logic lives in `aca_calc/`:
+
+1. `aca_calc/calculations/ptc.py`
+   - Builds household situations
+   - Applies ACA reform parameters when requested
+   - Returns PTC, SLCSP, FPL, and FPL percentage values
+
+2. `aca_calc/calculations/household.py`
+   - Builds PolicyEngine household dictionaries
+   - Handles spouse, dependent, county, ZIP, and income-axis structure
+
+3. `aca_calc/enrollment_context.py`
+   - Loads checked-in CMS Marketplace enrollment fixtures
+   - Labels HealthCare.gov-platform states versus fallback-only states
+   - Provides county and congressional district local context
 
 ### Data Files
 
-- **`counties.json`**: 3,143 counties across all 50 states + DC
-- **`process_counties.py`**: Updates county data from PolicyEngine
+- `counties.json`: counties across all states plus DC
+- `aca_calc/data/enrollment_context_2026_counties.json`: tiny county fixture
+- `aca_calc/data/enrollment_context_2026_districts.json`: tiny district fixture
+- `aca_calc/data/marketplace_platforms_2026.json`: state Marketplace platform config
+- `process_counties.py`: updates county data from PolicyEngine
 
 ## Testing
 
 ```bash
-# Quick verification test
-python tests/test_reform_verification.py
+npm run lint
+npm run build
+uv run pytest
+```
 
-# Comprehensive tests
-python tests/test_app_comprehensive.py
+For local impact work, the focused Python tests are:
 
-# State-specific tests
-python tests/test_texas.py
-python tests/test_nj.py
+```bash
+uv run pytest \
+  tests/test_enrollment_context.py \
+  tests/test_enrollment_ingest.py \
+  tests/test_congressional_district_ingest.py
 ```
 
 ## PolicyEngine Integration
@@ -49,70 +72,74 @@ python tests/test_nj.py
 situation = {
     "people": {...},
     "families": {...},
-    "spm_units": {...},      # Required!
+    "spm_units": {...},
     "tax_units": {...},
     "households": {...},
-    "marital_units": {...}   # If married/partnered
+    "marital_units": {...},
 }
 ```
 
-**Important**: Always include `spm_units` for accurate ACA calculations.
+Always include `spm_units` for accurate ACA calculations. Add
+`marital_units` when the household includes a spouse or child dependents.
 
 ### Reform Parameters
 
 IRA enhancements modify these PolicyEngine parameters:
+
 ```python
-"gov.aca.ptc_phase_out_rate[0-6].amount"  # Contribution percentages
-"gov.aca.ptc_income_eligibility[2].amount"  # Remove 400% FPL cap
+"gov.aca.ptc_phase_out_rate[0-6].amount"
+"gov.aca.ptc_income_eligibility[2].amount"
 ```
 
 ### County Format
 
-PolicyEngine expects: `COUNTY_NAME_STATE`
-- Examples: `TRAVIS_COUNTY_TX`, `BERGEN_COUNTY_NJ`
-- All caps, underscores instead of spaces
-- State abbreviation suffix
+PolicyEngine expects `COUNTY_NAME_STATE`:
+
+- `TRAVIS_COUNTY_TX`
+- `BERGEN_COUNTY_NJ`
+
+Use all caps, underscores instead of spaces, and a state abbreviation suffix.
 
 ## Common Issues
 
 ### SLCSP Returns $0
+
 - Check county name format
-- Verify state has marketplace data
-- Try without county (uses state default)
+- Verify state has Marketplace pricing data
+- Try without county to use the state default
 
 ### Reform Not Applied
-- Ensure `use_reform=True` parameter
-- Check Reform.from_dict() imports correctly
-- Verify date format: "2026-01-01.2100-12-31"
 
-### Calculations Don't Match Notebook
+- Ensure `use_reform=True`
+- Check `Reform.from_dict()` imports correctly
+- Verify date ranges use the expected PolicyEngine parameter format
+
+### Calculations Do Not Match Notebook Values
+
 - Check PolicyEngine version
 - Verify household structure matches
 - Confirm income is split correctly for couples
 
 ## Adding Features
 
 ### New State-Specific Logic
-1. Add to `calculate_ptc()` function
-2. Test with multiple counties in that state
-3. Compare against PolicyEngine web app
+
+1. Add reusable logic under `aca_calc/`.
+2. Wire UI behavior through React components in `src/`.
+3. Test with multiple counties or districts in that state.
 
 ### UI Changes
-1. Modify `main()` function
-2. Update session state handling
-3. Test with various household types
 
-### New Visualizations
-1. Add to or modify `create_chart()`
-2. Use Plotly for consistency
-3. Include hover tooltips
+1. Keep navigation in `src/App.jsx`.
+2. Keep calculator state in the calculator components.
+3. Match existing component and CSS conventions.
 
-## Performance Tips
+### New Visualizations
 
-- Use `@st.cache_data` for expensive operations
-- Load counties.json once at startup
-- Minimize redundant PolicyEngine simulations
+1. Prefer existing Recharts/D3 patterns.
+2. Keep chart data preparation separate from visual rendering.
+3. Include labels and hover states that work on desktop and mobile.
 
 ## Questions?
 
-Check PolicyEngine docs: https://policyengine.github.io/policyengine-us/
+Check PolicyEngine docs: https://policyengine.github.io/policyengine-us/

Makefile

@@ -11,7 +11,7 @@ format:
 	@echo "Formatting complete"
 
 debug:
-	uv run streamlit run app.py
+	npm run dev
 
 clean:
 	rm -rf __pycache__ .pytest_cache .coverage htmlcov

README.md

@@ -1,42 +1,54 @@
 # ACA Premium Tax Credit Calculator
 
-Compare 2026 Premium Tax Credits with and without Inflation Reduction Act (IRA) enhancements.
+Compare 2026 Premium Tax Credits with and without Inflation Reduction Act
+(IRA) enhancements, and pair household impacts with local Marketplace
+enrollment context.
 
-**🔗 [Try the Calculator](https://policyengine-aca-calc.streamlit.app/)**
+**Try the calculator:** https://www.policyengine.org/us/aca-calc#calculator
 
 ## Overview
 
-The Inflation Reduction Act enhanced ACA subsidies through 2025. This calculator shows what your credits would be in 2026 with and without extending these enhancements.
+The Inflation Reduction Act enhanced ACA subsidies through 2025. This
+calculator shows what household credits would be in 2026 with and without
+extending those enhancements.
 
-**Key Differences:**
-- **With IRA Extension**: No income cap, lower premium contributions (0-8.5% of income)
-- **After IRA Expires**: 400% FPL cap ("subsidy cliff"), higher contributions (2-9.5% of income)
+Key differences:
 
-## Quick Start
-
-### Use the Live App
+- **With IRA extension:** no income cap, lower premium contributions
+  (0-8.5% of income)
+- **After IRA expires:** 400% FPL cap ("subsidy cliff"), higher contributions
+  (2-9.5% of income)
+- **Local impact:** Marketplace enrollment context for HealthCare.gov-platform
+  geographies where fine-grained CMS PUF data are available
 
-Visit **[https://policyengine-aca-calc.streamlit.app/](https://policyengine-aca-calc.streamlit.app/)** to use the calculator immediately.
+## Quick Start
 
 ### Run Locally
 
 ```bash
-# Install dependencies
-pip install -r requirements.txt
-
-# Run the app
-streamlit run app.py
+npm install
+npm run dev
 ```
 
-The app will open at http://localhost:8501
+The React app runs at http://localhost:3000. The calculator is available at
+http://localhost:3000/#calculator.
+
+Python tests and data utilities use the Python package in `aca_calc/`:
+
+```bash
+uv run pytest
+```
 
 ## Features
 
-- ✅ **All 50 States + DC**: Accurate calculations for every jurisdiction
-- ✅ **3,143 Counties**: County-specific marketplace pricing
-- ✅ **Real-time Comparison**: Side-by-side baseline vs. IRA extension
-- ✅ **Interactive Charts**: See how credits change across income levels
-- ✅ **Household Flexibility**: Single, married, with/without dependents
+- All 50 states plus DC
+- County-specific ACA pricing inputs
+- Interactive household calculator for baseline, IRA extension, and additional
+  reform scenarios
+- Local impact page with county and congressional district Marketplace
+  enrollment context
+- Tiny checked-in CMS-style enrollment fixtures, structured for later ingestion
+  of processed full PUF files
 
 ## Example Results
 
@@ -50,32 +62,44 @@ The app will open at http://localhost:8501
 ## Technical Details
 
 Built with:
-- **[PolicyEngine US](https://policyengine.org)**: Open-source tax-benefit microsimulation
-- **[Streamlit](https://streamlit.io)**: Interactive web interface
-- **[Plotly](https://plotly.com)**: Data visualization
 
-County data sourced from PolicyEngine's ACA rating areas database.
+- **Next.js + React:** interactive web application
+- **PolicyEngine US:** open-source tax-benefit microsimulation
+- **Recharts + D3:** data visualization
+- **Python utilities:** enrollment fixture loaders and ingest helpers
+
+County data are sourced from PolicyEngine's ACA rating area data. Enrollment
+context starts with small checked-in fixtures under `aca_calc/data/` and can be
+repointed to processed CMS Marketplace PUF files later.
 
 ## Project Structure
 
-```
+```text
 .
-├── app.py                  # Main Streamlit application
-├── counties.json           # County data for all states
-├── process_counties.py     # County data processor
-├── requirements.txt        # Python dependencies
-├── tests/                  # Test files
-├── notebooks/              # Analysis notebooks
-└── archive/                # Historical files
+├── app/                         # Next.js app shell
+├── src/                         # React UI, pages, and client-side helpers
+│   ├── components/              # Calculator, charts, and shared components
+│   └── views/LocalImpact.jsx    # Local impact view
+├── aca_calc/                    # Python calculation and data-access helpers
+│   ├── calculations/            # PolicyEngine household/PTC utilities
+│   └── data/                    # Small checked-in enrollment fixtures
+├── tests/                       # Python unit tests
+├── package.json                 # React/Next scripts
+├── pyproject.toml               # Python package/dependencies
+└── requirements.txt             # Python runtime dependencies
 ```
 
 ## Development
 
 ```bash
-# Run tests
-python tests/test_reform_verification.py
+npm run lint
+npm run build
+uv run pytest
+```
+
+To update county data:
 
-# Update county data
+```bash
 python process_counties.py
 ```
 
@@ -85,4 +109,4 @@ Open source - see PolicyEngine US license for underlying calculations.
 
 ## Credits
 
-Calculations powered by [PolicyEngine US](https://github.com/PolicyEngine/policyengine-us)
+Calculations powered by [PolicyEngine US](https://github.com/PolicyEngine/policyengine-us).