diff --git a/src/lib.rs b/src/lib.rs
index a172cb6..05ea05a 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -85,7 +85,7 @@ mod reader;
 /// encoding function, the encoder will verify that the structure can be encoded
 /// within that limit.  This verification occurs before any bytes are written to
 /// the Writer, so recovering from an the error is possible.
-#[derive(Clone, Copy, Show, Hash, Eq, PartialEq, Ord, PartialOrd)]
+#[derive(Clone, Copy, Debug, Hash, Eq, PartialEq, Ord, PartialOrd)]
 pub enum SizeLimit {
     Infinite,
     Bounded(u64)
diff --git a/src/reader.rs b/src/reader.rs
index 55d0649..18859ea 100644
--- a/src/reader.rs
+++ b/src/reader.rs
@@ -7,7 +7,7 @@ use rustc_serialize::Decoder;
 
 use super::SizeLimit;
 
-#[derive(Eq, PartialEq, Clone, Show)]
+#[derive(Eq, PartialEq, Clone, Debug)]
 pub struct InvalidEncoding {
     desc: &'static str,
     detail: Option<String>,
@@ -28,7 +28,7 @@ impl fmt::Display for InvalidEncoding {
 ///
 /// If decoding from a Buffer, assume that the buffer has been left
 /// in an invalid state.
-#[derive(Eq, PartialEq, Clone, Show)]
+#[derive(Eq, PartialEq, Clone, Debug)]
 pub enum DecodingError {
     /// If the error stems from the reader that is being used
     /// during decoding, that error will be stored and returned here.
diff --git a/src/test.rs b/src/test.rs
index fb4735b..9ccb0be 100644
--- a/src/test.rs
+++ b/src/test.rs
@@ -64,7 +64,7 @@ fn test_tuple() {
 
 #[test]
 fn test_basic_struct() {
-    #[derive(RustcEncodable, RustcDecodable, PartialEq, Show)]
+    #[derive(RustcEncodable, RustcDecodable, PartialEq, Debug)]
     struct Easy {
         x: isize,
         s: String,
@@ -75,13 +75,13 @@ fn test_basic_struct() {
 
 #[test]
 fn test_nested_struct() {
-    #[derive(RustcEncodable, RustcDecodable, PartialEq, Show)]
+    #[derive(RustcEncodable, RustcDecodable, PartialEq, Debug)]
     struct Easy {
         x: isize,
         s: String,
         y: usize
     }
-    #[derive(RustcEncodable, RustcDecodable, PartialEq, Show)]
+    #[derive(RustcEncodable, RustcDecodable, PartialEq, Debug)]
     struct Nest {
         f: Easy,
         b: usize,
@@ -97,7 +97,7 @@ fn test_nested_struct() {
 
 #[test]
 fn test_struct_tuple() {
-    #[derive(RustcEncodable, RustcDecodable, PartialEq, Show)]
+    #[derive(RustcEncodable, RustcDecodable, PartialEq, Debug)]
     struct TubStr(usize, String, f32);
 
     the_same(TubStr(5, "hello".to_string(), 3.2));
@@ -112,7 +112,7 @@ fn option() {
 
 #[test]
 fn enm() {
-    #[derive(RustcEncodable, RustcDecodable, PartialEq, Show)]
+    #[derive(RustcEncodable, RustcDecodable, PartialEq, Debug)]
     enum TestEnum {
         NoArg,
         OneArg(usize),
@@ -126,7 +126,7 @@ fn enm() {
 
 #[test]
 fn struct_enum() {
-    #[derive(RustcEncodable, RustcDecodable, PartialEq, Show)]
+    #[derive(RustcEncodable, RustcDecodable, PartialEq, Debug)]
     enum TestEnum {
         NoArg,
         OneArg(usize),
@@ -232,3 +232,8 @@ fn test_encoded_size() {
 
     assert!(encoded_size(&vec![0u32, 1u32, 2u32]) == 8 + 3 * (4))
 }
+
+#[test]
+fn encode_box() {
+    the_same(Box::new(5));
+}