Migrate from setup.py to pyproject.toml (#3319)

* Migrate from setup.py to pyproject.toml with hatchling

Modernize build configuration to use pyproject.toml, consistent with
other PolicyEngine repositories. All dependencies, entry points, and
metadata preserved. Updated Makefile references accordingly.

Co-Authored-By: Claude Opus 4.6 <[email protected]>

* Add hatch wheel packages config for package discovery

Hatchling requires explicit package listing when there is no
__init__.py in the package directory.

Co-Authored-By: Claude Opus 4.6 <[email protected]>

---------

Co-authored-by: Claude Opus 4.6 <[email protected]>

Author: MaxGhenis

Makefile

@@ -1,5 +1,5 @@
 install:
-	pip install -e ".[dev]" --config-settings editable_mode=compat
+	pip install -e ".[dev]"
 	bash .github/setup_env.sh
 
 debug:
@@ -31,6 +31,6 @@ deploy:
 changelog:
 	build-changelog changelog.yaml --output changelog.yaml --update-last-date --start-from 0.1.0 --append-file changelog_entry.yaml
 	build-changelog changelog.yaml --org PolicyEngine --repo policyengine-api --output CHANGELOG.md --template .github/changelog_template.md
-	bump-version changelog.yaml setup.py policyengine_api/constants.py
+	bump-version changelog.yaml pyproject.toml policyengine_api/constants.py
 	rm changelog_entry.yaml || true
 	touch changelog_entry.yaml 

changelog_entry.yaml

@@ -0,0 +1,4 @@
+- bump: minor
+  changes:
+    changed:
+    - Migrated from setup.py to pyproject.toml with hatchling build backend

pyproject.toml

@@ -0,0 +1,67 @@
+[build-system]
+requires = ["hatchling"]
+build-backend = "hatchling.build"
+
+[project]
+name = "policyengine-api"
+version = "3.37.0"
+description = "PolicyEngine API"
+readme = "README.md"
+license = "AGPL-3.0-only"
+authors = [
+    { name = "PolicyEngine", email = "[email protected]" },
+]
+requires-python = ">=3.11"
+classifiers = [
+    "Programming Language :: Python :: 3",
+    "Programming Language :: Python :: 3.11",
+    "Programming Language :: Python :: 3.12",
+    "Programming Language :: Python :: 3.13",
+    "Programming Language :: Python :: 3.14",
+    "License :: OSI Approved :: GNU Affero General Public License v3",
+]
+dependencies = [
+    "anthropic",
+    "assertpy",
+    "click>=8,<9",
+    "cloud-sql-python-connector",
+    "faiss-cpu",
+    "flask>=3,<4",
+    "flask-cors>=5,<6",
+    "Flask-Caching>=2,<3",
+    "google-cloud-logging>=3,<4",
+    "gunicorn",
+    "httpx>=0.27.0",
+    "markupsafe>=3,<4",
+    "microdf_python>=1.0.0",
+    "openai",
+    "policyengine_canada==0.96.3",
+    "policyengine-ng==0.5.1",
+    "policyengine-il==0.1.0",
+    "policyengine_uk==2.39.0",
+    "policyengine_us==1.590.2",
+    "policyengine_core>=3.16.6",
+    "policyengine>=0.7.0",
+    "pydantic",
+    "pymysql",
+    "python-dotenv",
+    "redis",
+    "rq",
+    "sqlalchemy>=2,<3",
+    "streamlit",
+    "werkzeug",
+]
+
+[project.optional-dependencies]
+dev = [
+    "pytest-timeout",
+    "coverage",
+    "pytest-snapshot",
+    "ruff>=0.9.0",
+]
+
+[project.scripts]
+policyengine-api-setup = "policyengine_api.setup_data:setup_data"
+
+[tool.hatch.build.targets.wheel]
+packages = ["policyengine_api"]