diff --git a/pyproject.toml b/pyproject.toml
index f0ff8a0..56787ca 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -16,9 +16,9 @@ secondary = true
 [tool.poetry.dependencies]
 python = "^3.7"
 flax = "^0.3.4"
-PyYAML = "^5.4.1"
+PyYAML = ">=5.4.1"
 rich = "^10.7.0"
-optax = "^0.0.9"
+optax = ">=0.0.9"
 einops = "^0.3.2"
 treeo = "^0.0.9"
 # treeo = { path = "../treeo", develop = true }