diff --git a/.github/workflows/coverage.yml b/.github/workflows/coverage.yml
index 2898e39..da3a31e 100644
--- a/.github/workflows/coverage.yml
+++ b/.github/workflows/coverage.yml
@@ -31,7 +31,7 @@ jobs:
         run: |
           python -m pytest --cov=lazy_loader --durations=10
           # Tests fail if using `--doctest-modules`. I.e.,
-          # python -m pytest --cov=lazy_loader --doctest-modules --durations=20
+          # python -m pytest --cov=src --durations=10 --doctest-modules
 
       - name: Upload coverage to Codecov
         uses: codecov/codecov-action@v5
diff --git a/MANIFEST.in b/MANIFEST.in
index fc49293..ce1d4c7 100644
--- a/MANIFEST.in
+++ b/MANIFEST.in
@@ -1 +1,9 @@
 include CHANGELOG.md
+include .spin/cmds.py
+recursive-include tests *
+
+global-exclude *~
+global-exclude *.pyc
+
+prune */.pytest_cache
+prune */__pycache__
diff --git a/pyproject.toml b/pyproject.toml
index 36bd7a5..ba778f2 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -25,7 +25,7 @@ dependencies = [
 ]
 
 [project.optional-dependencies]
-test = ["pytest >= 8.0", "pytest-cov >= 5.0"]
+test = ["pytest >= 8.0", "pytest-cov >= 5.0", "coverage[toml] >= 7.2"]
 lint = ["pre-commit == 4.2.0"]
 dev = ["changelist == 0.5"]
 
@@ -48,7 +48,7 @@ log_cli_level = "info"
 
 [tool.ruff]
 exclude = [
-  "lazy_loader/tests/fake_pkg/__init__.pyi",
+  "tests/fake_pkg/__init__.pyi",
 ]
 
 [tool.ruff.lint]
@@ -92,3 +92,13 @@ ignore = [
 
 [tool.ruff.format]
 docstring-code-format = true
+
+[tool.coverage.run]
+branch = true
+source = ["lazy_loader", "tests"]
+
+[tool.coverage.paths]
+source = [
+  "src/lazy_loader",
+  "*/site-packages/lazy_loader",
+]
diff --git a/lazy_loader/__init__.py b/src/lazy_loader/__init__.py
similarity index 100%
rename from lazy_loader/__init__.py
rename to src/lazy_loader/__init__.py
diff --git a/lazy_loader/tests/__init__.py b/tests/__init__.py
similarity index 100%
rename from lazy_loader/tests/__init__.py
rename to tests/__init__.py
diff --git a/lazy_loader/tests/fake_pkg/__init__.py b/tests/fake_pkg/__init__.py
similarity index 100%
rename from lazy_loader/tests/fake_pkg/__init__.py
rename to tests/fake_pkg/__init__.py
diff --git a/lazy_loader/tests/fake_pkg/__init__.pyi b/tests/fake_pkg/__init__.pyi
similarity index 100%
rename from lazy_loader/tests/fake_pkg/__init__.pyi
rename to tests/fake_pkg/__init__.pyi
diff --git a/lazy_loader/tests/fake_pkg/some_func.py b/tests/fake_pkg/some_func.py
similarity index 100%
rename from lazy_loader/tests/fake_pkg/some_func.py
rename to tests/fake_pkg/some_func.py
diff --git a/lazy_loader/tests/import_np_parallel.py b/tests/import_np_parallel.py
similarity index 100%
rename from lazy_loader/tests/import_np_parallel.py
rename to tests/import_np_parallel.py
diff --git a/lazy_loader/tests/test_lazy_loader.py b/tests/test_lazy_loader.py
similarity index 97%
rename from lazy_loader/tests/test_lazy_loader.py
rename to tests/test_lazy_loader.py
index 9fcc783..e0d0221 100644
--- a/lazy_loader/tests/test_lazy_loader.py
+++ b/tests/test_lazy_loader.py
@@ -128,7 +128,7 @@ def test_lazy_attach_returns_copies():
 
 
 def test_attach_same_module_and_attr_name():
-    from lazy_loader.tests import fake_pkg
+    from tests import fake_pkg
 
     # Grab attribute twice, to ensure that importing it does not
     # override function by module
@@ -136,7 +136,7 @@ def test_attach_same_module_and_attr_name():
     assert isinstance(fake_pkg.some_func, types.FunctionType)
 
     # Ensure imports from submodule still work
-    from lazy_loader.tests.fake_pkg.some_func import some_func
+    from tests.fake_pkg.some_func import some_func
 
     assert isinstance(some_func, types.FunctionType)
 
@@ -157,7 +157,7 @@ def test_stub_loading(tmp_path):
 
 
 def test_stub_loading_parity():
-    from lazy_loader.tests import fake_pkg
+    from tests import fake_pkg
 
     from_stub = lazy.attach_stub(fake_pkg.__name__, fake_pkg.__file__)
     stub_getter, stub_dir, stub_all = from_stub