diff --git a/pyproject.toml b/pyproject.toml
index 0b9ab5a..1bdc1d3 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -24,6 +24,7 @@ classifiers = [
     'Topic :: Scientific/Engineering',
 ]
 dependencies = [
+    "importlib_resources; python_version<'3.9'",
     "pyusb>1.1.1",
     "pyvcd>=0.2.4",
     "prompt-toolkit>3.0.16",