diff --git a/pyproject.toml b/pyproject.toml
new file mode 100644
index 0000000..a3be834
--- /dev/null
+++ b/pyproject.toml
@@ -0,0 +1,19 @@
+[project]
+name = "spending-analysis"
+version = "0.1.0"
+requires-python = ">=3.12"
+dependencies = [
+    "PySide6>=6.6",
+    "sqlalchemy>=2.0",
+    "pandas>=2.0",
+    "matplotlib>=3.8",
+]
+
+[project.optional-dependencies]
+dev = [
+    "pytest>=8.0",
+    "pytest-qt>=4.2",
+]
+
+[project.scripts]
+spending-analysis = "src.main:main"
diff --git a/src/__init__.py b/src/__init__.py
new file mode 100644
index 0000000..e69de29
diff --git a/src/models/__init__.py b/src/models/__init__.py
new file mode 100644
index 0000000..e69de29
diff --git a/src/services/__init__.py b/src/services/__init__.py
new file mode 100644
index 0000000..e69de29
diff --git a/src/ui/__init__.py b/src/ui/__init__.py
new file mode 100644
index 0000000..e69de29
diff --git a/tests/__init__.py b/tests/__init__.py
new file mode 100644
index 0000000..e69de29
diff --git a/tests/models/__init__.py b/tests/models/__init__.py
new file mode 100644
index 0000000..e69de29
diff --git a/tests/services/__init__.py b/tests/services/__init__.py
new file mode 100644
index 0000000..e69de29