diff --git a/pkgs/development/compilers/rustc/0.12.nix b/pkgs/development/compilers/rustc/0.12.nix
index 7b7dc3198b47..9cbe3fec2c40 100644
--- a/pkgs/development/compilers/rustc/0.12.nix
+++ b/pkgs/development/compilers/rustc/0.12.nix
@@ -18,7 +18,7 @@ assert !stdenv.isFreeBSD;
 
 with ((import ./common.nix) {inherit stdenv; version = "0.12.0"; });
 
-let snapshot = if stdenv.system == "i686-linux"
+let snapshotHash = if stdenv.system == "i686-linux"
       then "555aca74f9a268f80cab2df1147dc6406403e9e4"
       else if stdenv.system == "x86_64-linux"
       then "6a43c2f6c8ba2cbbcb9da1f7b58f748aef99f431"
@@ -29,7 +29,7 @@ let snapshot = if stdenv.system == "i686-linux"
       else abort "no-snapshot for platform ${stdenv.system}";
     snapshotDate = "2014-10-04";
     snapshotRev = "749ff5e";
-    snapshotName = "rust-stage0-${snapshotDate}-${snapshotRev}-${platform}-${snapshot}.tar.bz2";
+    snapshotName = "rust-stage0-${snapshotDate}-${snapshotRev}-${platform}-${snapshotHash}.tar.bz2";
 
 in stdenv.mkDerivation {
   inherit name;
@@ -37,7 +37,7 @@ in stdenv.mkDerivation {
   inherit meta;
 
   src = fetchurl {
-    url = http://static.rust-lang.org/dist/rust-0.12.0.tar.gz;
+    url = "http://static.rust-lang.org/dist/rust-${version}.tar.gz";
     sha256 = "1dv9wxh41230zknbwj34zgjnh1kgvvy6k12kbiy9bnch9nr6cgl8";
   };
 
@@ -46,7 +46,7 @@ in stdenv.mkDerivation {
     name = "rust-stage0";
     src = fetchurl {
       url = "http://static.rust-lang.org/stage0-snapshots/${snapshotName}";
-      sha1 = snapshot;
+      sha1 = snapshotHash;
     };
     dontStrip = true;
     installPhase = ''
diff --git a/pkgs/development/compilers/rustc/common.nix b/pkgs/development/compilers/rustc/common.nix
index 915b54666346..8debb4342dac 100644
--- a/pkgs/development/compilers/rustc/common.nix
+++ b/pkgs/development/compilers/rustc/common.nix
@@ -21,7 +21,7 @@
     then "i686-apple-darwin"
     else if stdenv.system == "x86_64-darwin"
     then "x86_64-apple-darwin"
-    else abort "no snapshot to bootstrap for this platform (missing target triple";
+    else abort "no snapshot to bootstrap for this platform (missing target triple)";
 
   meta = with stdenv.lib; {
     homepage = http://www.rust-lang.org/;
diff --git a/pkgs/development/compilers/rustc/head.nix b/pkgs/development/compilers/rustc/head.nix
index b10e593ed39d..4899e51e2ef4 100644
--- a/pkgs/development/compilers/rustc/head.nix
+++ b/pkgs/development/compilers/rustc/head.nix
@@ -18,9 +18,14 @@ assert !stdenv.isFreeBSD;
 
 */
 
-with ((import ./common.nix) {inherit stdenv; version = "0.13.0-pre-3497-g6539cb4";});
+let shortVersion = "0.13-dev";
+    rev = "6539cb417f4a7c2d9d1afce44c196578d2b67f38";
+    revShort = builtins.substring 0 7 rev;
+in
 
-let snapshot = if stdenv.system == "i686-linux"
+with ((import ./common.nix) {inherit stdenv; version = "${shortVersion}-g${revShort}"; });
+
+let snapshotHash = if stdenv.system == "i686-linux"
       then "b880b98d832c9a049b8ef6a50df50061e363de5a"
       else if stdenv.system == "x86_64-linux"
       then "82a09c162474b69d2d1e4e8399086f3f0f4e31c3"
@@ -28,19 +33,20 @@ let snapshot = if stdenv.system == "i686-linux"
       then "569055bb10d96ab25f78ecf2c80ffbccd5e69b8d"
       else if stdenv.system == "x86_64-darwin"
       then "cff1f9ebd63dae6890359b7d353bd9486d8ecdfc"
-      else abort "no-snapshot for platform ${stdenv.system}";
+      else abort "no snapshot for platform ${stdenv.system}";
     snapshotDate = "2015-01-04";
     snapshotRev = "b2085d9";
-    snapshotName = "rust-stage0-${snapshotDate}-${snapshotRev}-${platform}-${snapshot}.tar.bz2";
+    snapshotName = "rust-stage0-${snapshotDate}-${snapshotRev}-${platform}-${snapshotHash}.tar.bz2";
+in
 
-in stdenv.mkDerivation {
+stdenv.mkDerivation {
   inherit name;
   inherit version;
   inherit meta;
 
   src = fetchgit {
     url = https://github.com/rust-lang/rust;
-    rev = "6539cb417f4a7c2d9d1afce44c196578d2b67f38";
+    inherit rev;
     sha256 = "14nc42j46hvlqms77245vil2wplmvci3ramxrmjyjqg0bql1w28m";
   };
 
@@ -49,7 +55,7 @@ in stdenv.mkDerivation {
     name = "rust-stage0";
     src = fetchurl {
       url = "http://static.rust-lang.org/stage0-snapshots/${snapshotName}";
-      sha1 = snapshot;
+      sha1 = snapshotHash;
     };
     dontStrip = true;
     installPhase = ''
diff --git a/pkgs/development/tools/build-managers/cargo/common.nix b/pkgs/development/tools/build-managers/cargo/common.nix
index 901fde593894..f0d8f92dfaa3 100644
--- a/pkgs/development/tools/build-managers/cargo/common.nix
+++ b/pkgs/development/tools/build-managers/cargo/common.nix
@@ -1,8 +1,8 @@
-{stdenv, fetchurl, zlib}:
+{stdenv, version}:
 
-with stdenv.lib;
+{
+  inherit version;
 
-rec {
   platform = if stdenv.system == "i686-linux"
     then "i686-unknown-linux-gnu"
     else if stdenv.system == "x86_64-linux"
@@ -13,40 +13,12 @@ rec {
     then "x86_64-apple-darwin"
     else throw "no snapshot to bootstrap for this platform (missing platform url suffix)";
 
-  snapshotHash = if stdenv.system == "i686-linux"
-    then "ab8bba0918d3d2ddbd7fd21f147e223dbf04cece"
-    else if stdenv.system == "x86_64-linux"
-    then "0efe0f7bcbcbeb5494affcc8a2207db448a08c45"
-    else if stdenv.system == "i686-darwin"
-    then "e5097005b0a27c186b8edee24982fd4c3ebba81e"
-    else if stdenv.system == "x86_64-darwin"
-    then "6c0bb776e5645fb93b67341b111c715f39b25511"
-    else throw "no snapshot for platform ${stdenv.system}";
-
-  snapshotDate = "2014-12-30";
-  snapshotName = "cargo-nightly-${platform}.tar.gz";
-
-  snapshot = stdenv.mkDerivation {
-    name = "cargo-snapshot-${snapshotDate}";
-    src = fetchurl {
-      url = "https://static-rust-lang-org.s3.amazonaws.com/cargo-dist/${snapshotDate}/${snapshotName}";
-      sha1 = snapshotHash;
-    };
-    dontStrip = true;
-    installPhase = ''
-      mkdir -p "$out"
-      cp -r bin "$out/bin"
-    '' + (if stdenv.isLinux then ''
-      patchelf --interpreter "${stdenv.glibc}/lib/${stdenv.cc.dynamicLinker}" \
-               --set-rpath "${stdenv.cc.gcc}/lib/:${stdenv.cc.gcc}/lib64/:${zlib}/lib" \
-               "$out/bin/cargo"
-    '' else "");
-  };
-
-  meta = {
+  meta = with stdenv.lib; {
     homepage = http://crates.io;
     description = "Downloads your Rust project's dependencies and builds your project";
     license = [ licenses.mit licenses.asl20 ];
     platforms = platforms.linux;
   };
+
+  name = "cargo-${version}";
 }
diff --git a/pkgs/development/tools/build-managers/cargo/snapshot.nix b/pkgs/development/tools/build-managers/cargo/snapshot.nix
index e86b19ca33eb..b873aee62f9e 100644
--- a/pkgs/development/tools/build-managers/cargo/snapshot.nix
+++ b/pkgs/development/tools/build-managers/cargo/snapshot.nix
@@ -2,6 +2,42 @@
 
 /* Cargo binary snapshot */
 
-with ((import ./common.nix) { inherit stdenv fetchurl zlib; });
+let snapshotDate = "2014-12-30";
+in
 
-snapshot // { inherit meta; }
+with ((import ./common.nix) { inherit stdenv; version = "snapshot-${snapshotDate}"; });
+
+let snapshotHash = if stdenv.system == "i686-linux"
+      then "ab8bba0918d3d2ddbd7fd21f147e223dbf04cece"
+      else if stdenv.system == "x86_64-linux"
+      then "0efe0f7bcbcbeb5494affcc8a2207db448a08c45"
+      else if stdenv.system == "i686-darwin"
+      then "e5097005b0a27c186b8edee24982fd4c3ebba81e"
+      else if stdenv.system == "x86_64-darwin"
+      then "6c0bb776e5645fb93b67341b111c715f39b25511"
+      else throw "no snapshot for platform ${stdenv.system}";
+    snapshotName = "cargo-nightly-${platform}.tar.gz";
+in
+
+
+stdenv.mkDerivation {
+  inherit name;
+  inherit version;
+  inherit meta;
+
+  src = fetchurl {
+    url = "https://static-rust-lang-org.s3.amazonaws.com/cargo-dist/${snapshotDate}/${snapshotName}";
+    sha1 = snapshotHash;
+  };
+
+  dontStrip = true;
+
+  installPhase = ''
+    mkdir -p "$out"
+    cp -r bin "$out/bin"
+  '' + (if stdenv.isLinux then ''
+    patchelf --interpreter "${stdenv.glibc}/lib/${stdenv.cc.dynamicLinker}" \
+             --set-rpath "${stdenv.cc.gcc}/lib/:${stdenv.cc.gcc}/lib64/:${zlib}/lib" \
+             "$out/bin/cargo"
+  '' else "");
+}