frontend: fix nix build

frontend/default.nix

@@ -1,8 +1,8 @@
-{ nixpkgs ? <nixpkgs>
-, config ? {}
+{ sources ? import ../nix/sources.nix
+, pkgs ? import sources.nixpkgs {}
 }:
 
-with (import nixpkgs config);
+with pkgs;
 
 let
   mkDerivation =
@@ -17,8 +17,7 @@ let
     stdenv.mkDerivation {
       inherit name src;
 
-      buildInputs = [ elmPackages.elm ]
-        ++ lib.optional outputJavaScript nodePackages_10_x.uglify-js;
+      buildInputs = [ elmPackages.elm ];
 
       buildPhase = pkgs.elmPackages.fetchElmDeps {
         elmPackages = import srcs;
@@ -34,11 +33,6 @@ let
         ${lib.concatStrings (map (module: ''
           echo "compiling ${elmfile module}"
           elm make ${elmfile module} --output $out/${module}.${extension} --docs $out/share/doc/${module}.json
-          ${lib.optionalString outputJavaScript ''
-            echo "minifying ${elmfile module}"
-            uglifyjs $out/${module}.${extension} --compress 'pure_funcs="F2,F3,F4,F5,F6,F7,F8,F9,A2,A3,A4,A5,A6,A7,A8,A9",pure_getters,keep_fargs=false,unsafe_comps,unsafe' \
-                | uglifyjs --mangle --output=$out/${module}.min.${extension}
-          ''}
         '') targets)}
       '';
     };

frontend/elm-srcs.nix

@@ -1,5 +1,10 @@
 {
 
+      "elm/json" = {
+        sha256 = "0kjwrz195z84kwywaxhhlnpl3p251qlbm5iz6byd6jky2crmyqyh";
+        version = "1.1.3";
+      };
+
       "elm/html" = {
         sha256 = "1n3gpzmpqqdsldys4ipgyl1zacn0kbpc3g4v3hdpiyfjlgh8bf3k";
         version = "1.0.0";
@@ -15,21 +20,41 @@
         version = "1.0.5";
       };
 
-      "elm/json" = {
-        sha256 = "0kjwrz195z84kwywaxhhlnpl3p251qlbm5iz6byd6jky2crmyqyh";
-        version = "1.1.3";
-      };
-
       "elm/url" = {
         sha256 = "0av8x5syid40sgpl5vd7pry2rq0q4pga28b4yykn9gd9v12rs3l4";
         version = "1.0.0";
       };
 
+      "elm/http" = {
+        sha256 = "008bs76mnp48b4dw8qwjj4fyvzbxvlrl4xpa2qh1gg2kfwyw56v1";
+        version = "2.0.0";
+      };
+
       "elm/time" = {
         sha256 = "0vch7i86vn0x8b850w1p69vplll1bnbkp8s383z7pinyg94cm2z1";
         version = "1.0.0";
       };
 
+      "rtfeldman/elm-iso8601-date-strings" = {
+        sha256 = "1fa5sslklldy0dq8bm0zdkb9ni50yxhb09xb6lgk00x55bmza9ik";
+        version = "1.1.3";
+      };
+
+      "elm/bytes" = {
+        sha256 = "02ywbf52akvxclpxwj9n04jydajcbsbcbsnjs53yjc5lwck3abwj";
+        version = "1.0.8";
+      };
+
+      "elm/file" = {
+        sha256 = "1rljcb41dl97myidyjih2yliyzddkr2m7n74x7gg46rcw4jl0ny8";
+        version = "1.0.5";
+      };
+
+      "elm/parser" = {
+        sha256 = "0a3cxrvbm7mwg9ykynhp7vjid58zsw03r63qxipxp3z09qks7512";
+        version = "1.1.0";
+      };
+
       "elm/virtual-dom" = {
         sha256 = "0q1v5gi4g336bzz1lgwpn5b1639lrn63d8y6k6pimcyismp2i1yg";
         version = "1.0.2";