diff --git a/Cargo.toml b/Cargo.toml
index 545281b..6a248cd 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -34,7 +34,7 @@ system-lua = ["pkg-config"]
 [dependencies]
 libc = { version = "0.2" }
 failure = { version = "0.1.2" }
-num-traits = { version = "0.2" }
+num-traits = { version = "0.2.6" }
 compiletest_rs = { version = "0.3", optional = true }
 
 [build-dependencies]