Harmonize pyproject.toml etc. across projects

.gitignore

@@ -1,11 +1,59 @@
 # Ignore the cloned package repositories in this meta-workspace
-ttsim/
 gettsim/
 gettsim-personas/
 soep-preparation/
+ttsim/
+
+# Claude Code
+.claude/
+
+# Distribution / packaging
+*.egg
+*.egg-info/
+*.manifest
+*.spec
+.eggs/
+.installed.cfg
+build/
+dist/
+MANIFEST
+sdist/
+wheels/
+
+# Documentation
+docs/_build/
+
+# IDE
+.idea/
+.vscode/
+
+# Jupyter
+.ipynb_checkpoints/
 
-# Common local/IDE noise (kept minimal; each repo can have its own .gitignore)
+# macOS
 .DS_Store
-*.pyc
-__pycache__/
+
+# pixi
 .pixi/
+node_modules/
+
+# Python
+__pycache__/
+*.py[cod]
+*.so
+*$py.class
+
+# Ruff
+.ruff_cache/
+
+# Testing
+.cache/
+.coverage
+.coverage.*
+.hypothesis/
+.pytest_cache/
+coverage.xml
+htmlcov/
+
+# Version file (generated by hatch-vcs)
+src/*/_version.py

.gitmodules

@@ -0,0 +1,4 @@
+[submodule ".ai-instructions"]
+	path = .ai-instructions
+	url = git@github.com:OpenSourceEconomics/ai-instructions.git
+	branch = make-submodule

.pre-commit-config.yaml

@@ -5,6 +5,10 @@ repos:
       - id: check-hooks-apply
       - id: check-useless-excludes
       # - id: identity  # Prints all files passed to pre-commits. Debugging.
+  - repo: https://github.com/tox-dev/pyproject-fmt
+    rev: v2.18.1
+    hooks:
+      - id: pyproject-fmt
   - repo: https://github.com/lyz-code/yamlfix
     rev: 1.19.1
     hooks:
@@ -13,51 +17,59 @@ repos:
     rev: v6.0.0
     hooks:
       - id: check-added-large-files
-        args: [--maxkb=10000]
+        args:
+          - --maxkb=10000
+      - id: check-ast
       - id: check-case-conflict
+      - id: check-docstring-first
       - id: check-merge-conflict
+      - id: check-toml
       - id: check-vcs-permalinks
       - id: check-yaml
-      - id: check-toml
       - id: debug-statements
       - id: end-of-file-fixer
       - id: fix-byte-order-marker
-        types: [text]
-      - id: forbid-submodules
+        types:
+          - text
       - id: mixed-line-ending
-        args: [--fix=lf]
+        args:
+          - --fix=lf
         description: Forces to replace line ending by the UNIX 'lf' character.
       - id: no-commit-to-branch
-        args: [--branch, main]
+        args:
+          - --branch
+          - main
       - id: trailing-whitespace
-      - id: check-ast
-      - id: check-docstring-first
   - repo: https://github.com/adrienverge/yamllint.git
-    rev: v1.37.1
+    rev: v1.38.0
     hooks:
       - id: yamllint
   - repo: https://github.com/astral-sh/ruff-pre-commit
-    rev: v0.14.10
+    rev: v0.15.6
     hooks:
       - id: ruff-check
-        types_or: [python, jupyter]
-        args: [--fix]
+        args:
+          - --fix
+        types_or:
+          - jupyter
+          - pyi
+          - python
       - id: ruff-format
-        types_or: [python, jupyter]
+        types_or:
+          - jupyter
+          - pyi
+          - python
   - repo: https://github.com/executablebooks/mdformat
     rev: 1.0.0
     hooks:
       - id: mdformat
-        additional_dependencies: [mdformat-gfm, mdformat-ruff]
-        args: [--wrap, '88']
-        files: (README.md|CHANGES.md|CODE_OF_CONDUCT.md)
-  # - repo: local
-  #   hooks:
-  #     - id: ty
-  #       name: ty
-  #       entry: ty
-  #       language: system
-  #       types: [python]
-  #       args: [--config-file=pyproject.toml]
+        additional_dependencies:
+          - mdformat-gfm
+          - mdformat-gfm-alerts
+          - mdformat-ruff
+        args:
+          - --wrap
+          - '88'
+        files: (AGENTS\.md|CLAUDE\.md|README\.md|CHANGES\.md|CODE_OF_CONDUCT\.md|modules/.*\.md|profiles/.*\.md)
 ci:
   autoupdate_schedule: monthly

.yamllint.yml

@@ -0,0 +1,36 @@
+---
+rules:
+  braces: enable
+  brackets: enable
+  colons: enable
+  commas: enable
+  comments:
+    level: warning
+  comments-indentation:
+    level: warning
+  document-end: disable
+  document-start:
+    level: warning
+  empty-lines: enable
+  empty-values: disable
+  float-values: disable
+  hyphens: enable
+  indentation: {spaces: 2}
+  key-duplicates: enable
+  key-ordering: disable
+  line-length:
+    allow-non-breakable-inline-mappings: true
+    allow-non-breakable-words: true
+    max: 88
+  new-line-at-end-of-file: enable
+  new-lines:
+    type: unix
+  octal-values: disable
+  quoted-strings: disable
+  trailing-spaces: enable
+  truthy:
+    level: warning
+yaml-files:
+  - '*.yaml'
+  - '*.yml'
+  - .yamllint

AGENTS.md

@@ -0,0 +1,94 @@
+@.ai-instructions/profiles/tier-a.md @.ai-instructions/modules/jax.md
+@.ai-instructions/modules/pandas.md @.ai-instructions/modules/optimagic.md
+@.ai-instructions/modules/plotting.md @.ai-instructions/modules/project-structure.md
+@.ai-instructions/modules/pytask.md @.ai-instructions/modules/ml-econometrics.md
+
+# dev-gettsim
+
+## Overview
+
+This is a [pixi](https://pixi.sh) workspace containing four related projects for the
+German tax and transfer microsimulation system:
+
+- **ttsim** (`ttsim/`) - Core computation engine with DAG-based architecture supporting
+  NumPy and JAX backends
+- **gettsim** (`gettsim/`) - German policy implementations (functions, parameters,
+  tests)
+- **gettsim-personas** (`gettsim-personas/`) - Example household personas for testing
+  and exploration
+- **soep-preparation** (`soep-preparation/`) - Data preparation for SOEP survey data
+
+Each subdirectory has its own `CLAUDE.md` with project-specific guidance. Refer to
+`ttsim/CLAUDE.md` and `gettsim/CLAUDE.md` for detailed architecture and conventions.
+
+## Build & Test
+
+```bash
+# Run all tests across all projects
+pixi run -e py314 tests
+
+# Run tests with JAX backend
+pixi run -e py314-jax tests-jax
+
+# Run tests for a specific project
+pixi run -e py314 tests ttsim/tests/
+pixi run -e py314 tests gettsim/src/gettsim/tests_germany/
+pixi run -e py314 tests gettsim-personas/tests/
+pixi run -e py314 tests soep-preparation/tests/
+
+# Run specific test
+pixi run -e py314 tests -k "test_end_to_end"
+
+# Type checking (all projects)
+pixi run ty
+
+# Type checking with JAX backend
+pixi run ty-jax
+
+# Quality checks (linting, formatting)
+prek run --all-files
+
+# Available environments: py314, py314-jax, py314-cuda, py314-metal, type-checking, type-checking-jax
+```
+
+## Command Rules
+
+Always use these command mappings:
+
+- **Python**: Use `pixi run python` instead of `python` or `python3`
+- **Type checker**: Use `pixi run ty` instead of running ty/mypy/pyright directly
+- **Tests**: Use `pixi run tests` instead of `pytest` directly
+- **Linting/formatting**: Use `prek run --all-files` instead of `ruff` directly
+- **All quality checks**: Use `prek run --all-files`
+
+Before finishing any task that modifies code, always run these three verification steps
+in order:
+
+1. `pixi run ty` (type checker)
+1. `prek run --all-files` (quality checks: linting, formatting, yaml, etc.)
+1. `pixi run -e py314 tests -n 7` (full test suite)
+
+## Architecture
+
+- **Two-level DAG system**: Interface DAG (high-level orchestration) and TT DAG (core
+  computation)
+- **Single entry point**: `gettsim.main()` or `ttsim.main()` with `MainTarget`,
+  `InputData`, `TTTargets` helpers
+- **Backend abstraction**: `"numpy"` or `"jax"` backends; use `xnp(backend)` for array
+  operations
+- **Qualified names (qnames)**: Double-underscore separated paths (e.g.,
+  `"kindergeld__betrag_m"`)
+- **German naming**: Policy code uses German (Kindergeld, Bürgergeld), infrastructure
+  uses English
+
+## Python Version
+
+The root workspace sets `requires-python = ">=3.11"` to match the most permissive
+sub-project (ttsim, gettsim, gettsim-personas all require `>=3.11`; soep-preparation
+requires `>=3.14`). The `ty` type checker uses this to determine what's valid at
+runtime, so it must stay consistent with the individual projects' constraints.
+
+## pytest Configuration
+
+The workspace uses `--import-mode=importlib` to handle test files with identical names
+across projects. This is configured in the root `pyproject.toml`.

CLAUDE.md

@@ -0,0 +1 @@
+@AGENTS.md

conftest.py

@@ -1,15 +1,12 @@
 from __future__ import annotations
 
-from typing import TYPE_CHECKING
+from types import ModuleType
+from typing import Literal
 
 import pytest
 from ttsim.interface_dag_elements.backend import dnp as ttsim_dnp
 from ttsim.interface_dag_elements.backend import xnp as ttsim_xnp
 
-if TYPE_CHECKING:
-    from types import ModuleType
-    from typing import Literal
-
 
 def pytest_addoption(parser):
     parser.addoption(