Filter out irrelevant files

release.nix

 { packages ? (_: []), systemPackages ? (_: []), pkgs ? import <nixpkgs> {}, rtsopts ? "-M3g -N2" }:
 
 let
-  src = pkgs.lib.cleanSource ./.;
+  cleanSource = name: type: let
+      baseName = baseNameOf (toString name);
+      lib = pkgs.lib;
+    in !(
+      (type == "directory" &&
+        (  baseName == ".git"
+        || baseName == "dist"
+        || baseName == ".stack-work"
+      ))                                                          ||
+      (type == "symlink"   && (lib.hasPrefix "result" baseName))  ||
+      lib.hasSuffix ".hi"    baseName                             ||
+      lib.hasSuffix ".ipynb" baseName                             ||
+      lib.hasSuffix ".nix"   baseName                             ||
+      lib.hasSuffix ".o"     baseName                             ||
+      lib.hasSuffix ".sock"  baseName                             ||
+      lib.hasSuffix ".yaml"  baseName
+    );
+  src = builtins.filterSource cleanSource ./.;
   displays = self: builtins.listToAttrs (
     map
       (display: { name = display; value = self.callCabal2nix display "${src}/ihaskell-display/${display}" {}; })