diff --git a/MANIFEST.in b/MANIFEST.in
new file mode 100644
index 0000000..5ea09b2
--- /dev/null
+++ b/MANIFEST.in
@@ -0,0 +1,3 @@
+graft tests
+
+global-exclude *~ *.py[cod] *.so
\ No newline at end of file
diff --git a/pyproject.toml b/pyproject.toml
index fa617e8..955bf5a 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -85,8 +85,6 @@ include = ["prolif*"]
 [tool.setuptools.package-data]
 "prolif.data" = ["*"]
 "prolif.data.vina" = ["*"]
-"tests" = ["*"]
-"tests.plotting" = ["*"]
 
 [tool.setuptools.dynamic]
 version = { attr = "prolif._version.__version__" }