From 3f349cb0de0bbde2738ad175adf9dc8d697e1805 Mon Sep 17 00:00:00 2001
From: Peter Simons <simons@cryp.to>
Date: Sat, 1 Nov 2014 16:56:03 +0100
Subject: [PATCH] haskell-snap: jailbreak to fix build with latest version of
 'lens'

---
 pkgs/development/libraries/haskell/snap/snap.nix | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/pkgs/development/libraries/haskell/snap/snap.nix b/pkgs/development/libraries/haskell/snap/snap.nix
index c28ee69fb2c..14769499c21 100644
--- a/pkgs/development/libraries/haskell/snap/snap.nix
+++ b/pkgs/development/libraries/haskell/snap/snap.nix
@@ -21,7 +21,9 @@ cabal.mkDerivation (self: {
     snapCore snapServer stm syb text time transformers
     unorderedContainers vector vectorAlgorithms xmlhtml
   ];
-  jailbreak = true;
+  patchPhase = ''
+    sed -i -e 's|lens *>=.*|lens|' snap.cabal
+  '';
   meta = {
     homepage = "http://snapframework.com/";
     description = "Top-level package for the Snap Web Framework";