diff --git a/Cargo.toml b/Cargo.toml
index 54c0a51..7761124 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -11,7 +11,7 @@ categories = ["authentication"]
 license = "Apache-2.0/MIT"
 
 [dependencies]
-atomicwrites = "0.2.1"
+atomicwrites = "0.4.0"
 error-chain = "0.11.0"
 futures = "0.1.13"
 futures-error-chain = "0.1.0"