diff --git a/pyproject.toml b/pyproject.toml
index 71f48ad..0dbb9b4 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -92,7 +92,7 @@ dev-pytest = [
   "frequenz-repo-config[extra-lint-examples] == 0.13.8",
   "pytest-mock == 3.15.1",
   "pytest-asyncio == 1.3.0",
-  "async-solipsism == 0.8",
+  "async-solipsism == 0.9",
 ]
 dev = [
   "frequenz-client-microgrid[dev-mkdocs,dev-flake8,dev-formatting,dev-mkdocs,dev-mypy,dev-noxfile,dev-pylint,dev-pytest]",