diff --git a/util/Cargo.toml b/util/Cargo.toml
index ad51295fb..0936eae16 100644
--- a/util/Cargo.toml
+++ b/util/Cargo.toml
@@ -12,7 +12,8 @@ log = "0.3"
 env_logger = "0.3"
 rustc-serialize = "0.3"
 arrayvec = "0.3"
-mio = "0.5.0"
+mio = "0.5.1"
+nix ="0.5.0"
 rand = "0.3.12"
 time = "0.1.34"
 tiny-keccak = "1.0"