diff --git a/pyproject.toml b/pyproject.toml
index aef0fc9b..4430627a 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -21,7 +21,7 @@ authors = [{ name = "F. F. Martinez Gamo" }]
 python = "^3.10"
 # Minimal core - truly minimal for primality testing
 networkx = {version = "^2.6", optional = true}
-cachetools = {version = "^5.0", optional = true}
+cachetools = {version = "^6.2", optional = true}
 numpy = {version = "^1.24", optional = true}
 scipy = {version = "^1.9", optional = true}
 sympy = {version = "^1.10", optional = true}