diff --git a/pyproject.toml b/pyproject.toml
index 38a50df..5950d64 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -39,7 +39,7 @@ dependencies = [
   # Make sure to update the version for cross-referencing also in the
   # mkdocs.yml file when changing the version here (look for the config key
   # plugins.mkdocstrings.handlers.python.import)
-  "frequenz-sdk == 1.0.0-rc900",
+  "frequenz-sdk == 1.0.0-rc900, < 1.0.0-rc1000",
   "frequenz-channels >= 1.1.0, < 2.0.0",
   "frequenz-client-dispatch >= 0.6.0, < 0.7.0",
 ]