diff --git a/pyproject.toml b/pyproject.toml
index dcff4fa..281d4d1 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -20,7 +20,7 @@ black = "^23.7.0"
 flake8 = "^6.1.0"
 coverage = "^7.3.1"
 pytest = "^7.4.1"
-snakemake = "^8.18.0"
+snakemake = ">=8.18,<10.0"
 snakemake-storage-plugin-s3 = "^0.2.7"
 
 [tool.coverage.run]