diff --git a/pyproject.toml b/pyproject.toml
index ba496ebfce1..b50e9bfc8c7 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -159,7 +159,7 @@ full = [
     "pyx>=0.15",
     "scipy>=1.5.0",
     "glue-core!=1.2.4;python_version >= '3.10'",  # see https://github.com/glue-viz/glue/issues/2263
-    "ratarmount~=0.8.1;platform_system!='Windows' and platform_system!='Darwin'",
+    "ratarmount>=0.8.1,<0.10.0; platform_system!='Windows'",
     "yt[adaptahop]",
     "yt[ahf]",
     "yt[amrex]",