diff --git a/pkgs/development/haskell-modules/configuration-ghc-7.10.x.nix b/pkgs/development/haskell-modules/configuration-ghc-7.10.x.nix
index 87626eace6a3..b089e3b3fa00 100644
--- a/pkgs/development/haskell-modules/configuration-ghc-7.10.x.nix
+++ b/pkgs/development/haskell-modules/configuration-ghc-7.10.x.nix
@@ -292,4 +292,10 @@ self: super: {
   diagrams-core = overrideCabal super.diagrams-core (drv: {
     prePatch = "sed -i 's|4\.8|4.9|' diagrams-core.cabal";
   });
+
+  # diagrams/diagrams-core#83
+  diagrams-lib = overrideCabal super.diagrams-lib (drv: {
+    prePatch = "sed -i 's|4\.8|4.9|' diagrams-lib.cabal";
+    patches = [ ./diagrams-lib-flexible-contexts.patch ];
+  });
 }
diff --git a/pkgs/development/haskell-modules/diagrams-lib-flexible-contexts.patch b/pkgs/development/haskell-modules/diagrams-lib-flexible-contexts.patch
new file mode 100644
index 000000000000..385bc75b5823
--- /dev/null
+++ b/pkgs/development/haskell-modules/diagrams-lib-flexible-contexts.patch
@@ -0,0 +1,11 @@
+diff -Naur diagrams-lib-1.2.0.9-orig/src/Diagrams/TwoD/Polygons.hs diagrams-lib-1.2.0.9/src/Diagrams/TwoD/Polygons.hs
+--- diagrams-lib-1.2.0.9-orig/src/Diagrams/TwoD/Polygons.hs	2015-04-02 22:13:26.000000000 -0400
++++ diagrams-lib-1.2.0.9/src/Diagrams/TwoD/Polygons.hs	2015-04-11 18:17:28.095156620 -0400
+@@ -4,6 +4,7 @@
+ {-# LANGUAGE TemplateHaskell           #-}
+ {-# LANGUAGE TypeFamilies              #-}
+ {-# LANGUAGE ViewPatterns              #-}
++{-# LANGUAGE FlexibleContexts          #-}
+ 
+ -----------------------------------------------------------------------------
+ -- |