diff --git a/src/libextra/lib.rs b/src/libextra/lib.rs
index 70a21da6816..e0200f48cfe 100644
--- a/src/libextra/lib.rs
+++ b/src/libextra/lib.rs
@@ -59,11 +59,9 @@ pub mod url;
 pub mod json;
 pub mod tempfile;
 pub mod time;
-pub mod base64;
 pub mod workcache;
 pub mod enum_set;
 pub mod stats;
-pub mod hex;
 
 #[cfg(unicode)]
 mod unicode;
diff --git a/src/librustc/back/link.rs b/src/librustc/back/link.rs
index 72ae70565a7..957ca3b46c9 100644
--- a/src/librustc/back/link.rs
+++ b/src/librustc/back/link.rs
@@ -34,7 +34,7 @@ use std::run;
 use std::str;
 use std::io;
 use std::io::fs;
-use extra::hex::ToHex;
+use serialize::hex::ToHex;
 use extra::tempfile::TempDir;
 use syntax::abi;
 use syntax::ast;
diff --git a/src/librustc/util/sha2.rs b/src/librustc/util/sha2.rs
index 116ec6bba29..940cebf7847 100644
--- a/src/librustc/util/sha2.rs
+++ b/src/librustc/util/sha2.rs
@@ -16,7 +16,7 @@ use std::iter::range_step;
 use std::num::Zero;
 use std::vec;
 use std::vec::bytes::{MutableByteVector, copy_memory};
-use extra::hex::ToHex;
+use serialize::hex::ToHex;
 
 /// Write a u32 into a vector, which must be 4 bytes long. The value is written in big-endian
 /// format.
@@ -529,7 +529,7 @@ mod tests {
     use std::vec;
     use std::rand::isaac::IsaacRng;
     use std::rand::Rng;
-    use extra::hex::FromHex;
+    use serialize::hex::FromHex;
 
     // A normal addition - no overflow occurs
     #[test]
diff --git a/src/libextra/base64.rs b/src/libserialize/base64.rs
similarity index 97%
rename from src/libextra/base64.rs
rename to src/libserialize/base64.rs
index 556032af1ac..c22eefdb330 100644
--- a/src/libextra/base64.rs
+++ b/src/libserialize/base64.rs
@@ -63,8 +63,8 @@ impl<'a> ToBase64 for &'a [u8] {
      * # Example
      *
      * ```rust
-     * extern mod extra;
-     * use extra::base64::{ToBase64, STANDARD};
+     * extern mod serialize;
+     * use serialize::base64::{ToBase64, STANDARD};
      *
      * fn main () {
      *     let str = [52,32].to_base64(STANDARD);
@@ -189,8 +189,8 @@ impl<'a> FromBase64 for &'a str {
      * This converts a string literal to base64 and back.
      *
      * ```rust
-     * extern mod extra;
-     * use extra::base64::{ToBase64, FromBase64, STANDARD};
+     * extern mod serialize;
+     * use serialize::base64::{ToBase64, FromBase64, STANDARD};
      * use std::str;
      *
      * fn main () {
@@ -261,8 +261,8 @@ impl<'a> FromBase64 for &'a str {
 
 #[cfg(test)]
 mod test {
-    use test::BenchHarness;
-    use base64::*;
+    use extra::test::BenchHarness;
+    use base64::{Config, FromBase64, ToBase64, STANDARD, URL_SAFE};
 
     #[test]
     fn test_to_base64_basic() {
diff --git a/src/libextra/hex.rs b/src/libserialize/hex.rs
similarity index 96%
rename from src/libextra/hex.rs
rename to src/libserialize/hex.rs
index d4e1ae12337..409bf4af809 100644
--- a/src/libextra/hex.rs
+++ b/src/libserialize/hex.rs
@@ -28,7 +28,8 @@ impl<'a> ToHex for &'a [u8] {
      * # Example
      *
      * ```rust
-     * use extra::hex::ToHex;
+     * extern mod serialize;
+     * use serialize::hex::ToHex;
      *
      * fn main () {
      *     let str = [52,32].to_hex();
@@ -88,7 +89,8 @@ impl<'a> FromHex for &'a str {
      * This converts a string literal to hexadecimal and back.
      *
      * ```rust
-     * use extra::hex::{FromHex, ToHex};
+     * extern mod serialize;
+     * use serialize::hex::{FromHex, ToHex};
      * use std::str;
      *
      * fn main () {
@@ -137,8 +139,8 @@ impl<'a> FromHex for &'a str {
 
 #[cfg(test)]
 mod tests {
-    use test::BenchHarness;
-    use hex::*;
+    use extra::test::BenchHarness;
+    use hex::{FromHex, ToHex};
 
     #[test]
     pub fn test_to_hex() {
diff --git a/src/libserialize/lib.rs b/src/libserialize/lib.rs
index 5f473b25369..3b71b2237b1 100644
--- a/src/libserialize/lib.rs
+++ b/src/libserialize/lib.rs
@@ -30,4 +30,8 @@ pub use self::serialize::{Decoder, Encoder, Decodable, Encodable,
     DecoderHelpers, EncoderHelpers};
 
 mod serialize;
+
+pub mod base64;
 pub mod ebml;
+pub mod hex;
+