diff --git a/beeref/assets/__init__.py b/beeref/assets/__init__.py
index ed8bff5..2778317 100644
--- a/beeref/assets/__init__.py
+++ b/beeref/assets/__init__.py
@@ -38,6 +38,7 @@ class BeeAssets:
         logger.debug(f'Assets path: {self.PATH}')
 
         self.logo = QtGui.QIcon(os.path.join(self.PATH, 'logo.png'))
+        assert self.logo.isNull() is False
         self.cursor_rotate = self.cursor_from_image(
             'cursor_rotate.png', (20, 20))
         self.cursor_flip_h = self.cursor_from_image(
@@ -49,6 +50,7 @@ class BeeAssets:
         app = QtWidgets.QApplication.instance()
         scaling = app.primaryScreen().devicePixelRatio()
         img = QtGui.QImage(os.path.join(self.PATH, filename))
+        assert img.isNull() is False
         pixmap = QtGui.QPixmap.fromImage(img)
         pixmap.setDevicePixelRatio(scaling)
         return QtGui.QCursor(
diff --git a/pyproject.toml b/pyproject.toml
index e947a3c..e1cb30e 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -1,10 +1,13 @@
 [build-system]
-requires = ["setuptools"]
+requires = ["setuptools>=61.0.0"]
 build-backend = "setuptools.build_meta"
 
 [tool.setuptools.packages.find]
 include = ["beeref*"]
 
+[tool.setuptools.package-data]
+"*" = ["*.html", "*.png"]
+
 [project]
 name = "BeeRef"
 version = "0.3.4-dev"