diff --git a/Cargo.toml b/Cargo.toml
index ca5af728ce..4745cef5ae 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -20,12 +20,12 @@ preadv_pwritev = []
 signalfd = []
 
 [dependencies]
-libc     = "0.2.4"
-bitflags = "0.3.3"
+libc     = "^0.2.4"
+bitflags = "^0.3.3"
 
 [dev-dependencies]
-rand = "0.3.8"
-tempdir = "0.3"
+rand    = "^0.3.13"
+tempdir = "^0.3.4"
 
 [dev-dependencies.nix-test]
 path    = "nix-test"