diff --git a/.travis.yml b/.travis.yml
index 42fe126..92a2bad 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -1,4 +1,5 @@
 language: rust
+sudo: false
 rust:
     - stable
     - beta
diff --git a/Cargo.toml b/Cargo.toml
index ef4d6d2..0d3ca72 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -13,8 +13,8 @@ description = "A binary serialization / deserialization strategy and implementat
 [dependencies]
 rustc-serialize = "0.3.*"
 byteorder = "0.4.*"
-num = "*"
-serde = "*"
+num = "^0.1"
+serde = "^0.6"
 
 [dev-dependencies]
 serde_macros = "*"