diff --git a/pkgs/development/compilers/ghc/6.10.1-binary.nix b/pkgs/development/compilers/ghc/6.10.1-binary.nix
index c43f8525a33f..5a15cc0dff7e 100644
--- a/pkgs/development/compilers/ghc/6.10.1-binary.nix
+++ b/pkgs/development/compilers/ghc/6.10.1-binary.nix
@@ -1,6 +1,10 @@
 {stdenv, fetchurl, perl, libedit, ncurses, gmp}:
 
-assert stdenv.system == "i686-darwin" || stdenv.system == "x86_64-linux" || stdenv.system == "i686-linux";
+let
+  supportedPlatforms = ["i686-darwin" "x86_64-linux" "i686-linux"];
+in
+
+assert stdenv.lib.elem stdenv.system supportedPlatforms;
 
 stdenv.mkDerivation rec {
   version = "6.10.1";
@@ -100,5 +104,5 @@ stdenv.mkDerivation rec {
         [ $(./main) == "yes" ]
       '';
 
-  meta.platforms = stdenv.lib.platforms.haskellPlatforms;
+  meta.platforms = supportedPlatforms;
 }
diff --git a/pkgs/development/compilers/ghc/6.10.2-binary.nix b/pkgs/development/compilers/ghc/6.10.2-binary.nix
index 1f917d3029a1..bd80a4cab1a1 100644
--- a/pkgs/development/compilers/ghc/6.10.2-binary.nix
+++ b/pkgs/development/compilers/ghc/6.10.2-binary.nix
@@ -1,6 +1,10 @@
 {stdenv, fetchurl, perl, libedit, ncurses, gmp}:
 
-assert stdenv.system == "i686-darwin" || stdenv.system == "x86_64-linux" || stdenv.system == "i686-linux";
+let
+  supportedPlatforms = ["i686-darwin" "x86_64-linux" "i686-linux"];
+in
+
+assert stdenv.lib.elem stdenv.system supportedPlatforms;
 
 stdenv.mkDerivation rec {
   version = "6.10.2";
@@ -99,4 +103,5 @@ stdenv.mkDerivation rec {
         [ $(./main) == "yes" ]
       '';
 
+  meta.platforms = supportedPlatforms;
 }
diff --git a/pkgs/development/compilers/ghc/6.12.1-binary.nix b/pkgs/development/compilers/ghc/6.12.1-binary.nix
index b0a0bae890c9..6394780eb68c 100644
--- a/pkgs/development/compilers/ghc/6.12.1-binary.nix
+++ b/pkgs/development/compilers/ghc/6.12.1-binary.nix
@@ -1,6 +1,10 @@
 {stdenv, fetchurl, perl, ncurses, gmp}:
 
-assert stdenv.system == "i686-darwin" || stdenv.system == "x86_64-linux" || stdenv.system == "i686-linux";
+let
+  supportedPlatforms = ["x86_64-linux" "i686-linux"];
+in
+
+assert stdenv.lib.elem stdenv.system supportedPlatforms;
 
 stdenv.mkDerivation rec {
   version = "6.12.1";
@@ -101,4 +105,5 @@ stdenv.mkDerivation rec {
         [ $(./main) == "yes" ]
       '';
 
+  meta.platforms = supportedPlatforms;
 }
diff --git a/pkgs/development/compilers/ghc/6.4.2-binary.nix b/pkgs/development/compilers/ghc/6.4.2-binary.nix
index 50a49b728d78..63cc08db34b1 100644
--- a/pkgs/development/compilers/ghc/6.4.2-binary.nix
+++ b/pkgs/development/compilers/ghc/6.4.2-binary.nix
@@ -1,6 +1,10 @@
 {stdenv, fetchurl, perl, readline, ncurses, gmp}:
 
-assert stdenv.system == "i686-darwin" || stdenv.system == "x86_64-linux" || stdenv.system == "i686-linux";
+let
+  supportedPlatforms = ["i686-darwin" "x86_64-linux" "i686-linux"];
+in
+
+assert stdenv.lib.elem stdenv.system supportedPlatforms;
 
 stdenv.mkDerivation {
   name = if stdenv.system == "i686-darwin" then "ghc-6.6.1-binary" else "ghc-6.4.2-binary";
@@ -64,4 +68,5 @@ stdenv.mkDerivation {
 
   '' else "";
 
+  meta.platforms = supportedPlatforms;
 }