Add pyproject.toml and update CI for reproducible Python environment

- Add export/pyproject.toml with numpy, ase, pytest dependencies
- Update export-ci.yml to use uv for Python dependency management
- Include liblammps.so* in LAMMPS artifact for runtime linking
- Set LD_LIBRARY_PATH for LAMMPS shared library in CI
- Add export/.gitignore for venv and build artifacts

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <[email protected]>

Author: jameskermode

.github/workflows/export-ci.yml

@@ -71,6 +71,7 @@ jobs:
           name: lammps-build
           path: |
             lammps/build/lmp
+            lammps/build/liblammps.so*
             lammps/src/*.h
           retention-days: 1
 
@@ -128,10 +129,14 @@ jobs:
         uses: actions/setup-python@v5
         with:
           python-version: '3.11'
-          cache: 'pip'
+
+      - name: Install uv
+        uses: astral-sh/setup-uv@v4
 
       - name: Install Python dependencies
-        run: pip install numpy ase pytest
+        run: |
+          cd export
+          uv sync
 
       - name: Cache Julia packages
         uses: actions/cache@v4
@@ -157,6 +162,7 @@ jobs:
 
       - name: Run Python tests
         run: |
+          source export/.venv/bin/activate
           julia --project=export export/test/runtests.jl python
 
   test-lammps-serial:
@@ -181,6 +187,7 @@ jobs:
         run: |
           chmod +x lammps/build/lmp
           echo "$GITHUB_WORKSPACE/lammps/build" >> $GITHUB_PATH
+          echo "LD_LIBRARY_PATH=$GITHUB_WORKSPACE/lammps/build:$LD_LIBRARY_PATH" >> $GITHUB_ENV
 
       - name: Cache Julia packages
         uses: actions/cache@v4
@@ -284,6 +291,7 @@ jobs:
         run: |
           chmod +x lammps/build/lmp
           echo "$GITHUB_WORKSPACE/lammps/build" >> $GITHUB_PATH
+          echo "LD_LIBRARY_PATH=$GITHUB_WORKSPACE/lammps/build:$LD_LIBRARY_PATH" >> $GITHUB_ENV
 
       - name: Cache Julia packages
         uses: actions/cache@v4

export/.gitignore

@@ -0,0 +1,16 @@
+# Python virtual environment
+.venv/
+__pycache__/
+*.pyc
+
+# uv lock file (generated)
+uv.lock
+
+# Test artifacts
+test/build/
+test/lammps/*.dump
+test/lammps/*.log
+test/lammps/log.lammps
+
+# LAMMPS plugin build
+lammps/plugin/build/

export/pyproject.toml

@@ -0,0 +1,21 @@
+[project]
+name = "ace-export-tests"
+version = "0.1.0"
+description = "Python dependencies for ACE export testing"
+requires-python = ">=3.9"
+dependencies = [
+    "numpy>=1.20",
+    "ase>=3.22",
+    "pytest>=7.0",
+]
+
+[project.optional-dependencies]
+dev = [
+    "pytest-cov",
+]
+
+[tool.pytest.ini_options]
+testpaths = ["test/python"]
+python_files = ["test_*.py"]
+python_classes = ["Test*"]
+python_functions = ["test_*"]