diff --git a/pkgs/development/libraries/haskell/amazonka-cloudwatch/default.nix b/pkgs/development/libraries/haskell/amazonka-cloudwatch/default.nix
deleted file mode 100644
index 16660edfe73..00000000000
--- a/pkgs/development/libraries/haskell/amazonka-cloudwatch/default.nix
+++ /dev/null
@@ -1,16 +0,0 @@
-# This file was auto-generated by cabal2nix. Please do NOT edit manually!
-
-{ cabal, amazonkaCore }:
-
-cabal.mkDerivation (self: {
-  pname = "amazonka-cloudwatch";
-  version = "0.0.4";
-  sha256 = "1lsf5il184c1ldjhg3x32c1dzlba3r3q3fpzpam3kwyzz54d4k79";
-  buildDepends = [ amazonkaCore ];
-  meta = {
-    homepage = "https://github.com/brendanhay/amazonka";
-    description = "Amazon CloudWatch SDK";
-    license = "unknown";
-    platforms = self.ghc.meta.platforms;
-  };
-})
diff --git a/pkgs/development/libraries/haskell/amazonka-core/default.nix b/pkgs/development/libraries/haskell/amazonka-core/default.nix
deleted file mode 100644
index b7fa286d4e2..00000000000
--- a/pkgs/development/libraries/haskell/amazonka-core/default.nix
+++ /dev/null
@@ -1,30 +0,0 @@
-# This file was auto-generated by cabal2nix. Please do NOT edit manually!
-
-{ cabal, aeson, attoparsec, base16Bytestring, base64Bytestring
-, bifunctors, caseInsensitive, conduit, conduitExtra, cryptohash
-, cryptohashConduit, dataDefaultClass, hashable, httpClient
-, httpTypes, lens, mmorph, mtl, nats, resourcet, semigroups, tagged
-, tasty, tastyHunit, text, time, transformers, unorderedContainers
-, vector, xmlConduit
-}:
-
-cabal.mkDerivation (self: {
-  pname = "amazonka-core";
-  version = "0.0.4";
-  sha256 = "1h3bp4d13mg3n935qgw5dhwadb4ivcd3m8jk9l90jcgkgsni0zy4";
-  buildDepends = [
-    aeson attoparsec base16Bytestring base64Bytestring bifunctors
-    caseInsensitive conduit conduitExtra cryptohash cryptohashConduit
-    dataDefaultClass hashable httpClient httpTypes lens mmorph mtl nats
-    resourcet semigroups tagged text time transformers
-    unorderedContainers vector xmlConduit
-  ];
-  testDepends = [ tasty tastyHunit text time ];
-  jailbreak = true;
-  meta = {
-    homepage = "https://github.com/brendanhay/amazonka";
-    description = "Core functionality, serialisation primitives, and data types for the Amazonka Amazon Web Services SDKs";
-    license = "unknown";
-    platforms = self.ghc.meta.platforms;
-  };
-})
diff --git a/pkgs/development/libraries/haskell/amazonka/default.nix b/pkgs/development/libraries/haskell/amazonka/default.nix
deleted file mode 100644
index fabbe13b37e..00000000000
--- a/pkgs/development/libraries/haskell/amazonka/default.nix
+++ /dev/null
@@ -1,22 +0,0 @@
-# This file was auto-generated by cabal2nix. Please do NOT edit manually!
-
-{ cabal, amazonkaCore, conduit, exceptions, httpConduit, lens
-, mmorph, monadControl, mtl, resourcet, text, time
-, transformersBase
-}:
-
-cabal.mkDerivation (self: {
-  pname = "amazonka";
-  version = "0.0.4";
-  sha256 = "12hwkrn7azs1sxx9f5agk875y6r6wvjxmmx0xg3034p6ipjvh883";
-  buildDepends = [
-    amazonkaCore conduit exceptions httpConduit lens mmorph
-    monadControl mtl resourcet text time transformersBase
-  ];
-  meta = {
-    homepage = "https://github.com/brendanhay/amazonka";
-    description = "Comprehensive Amazon Web Services SDK";
-    license = "unknown";
-    platforms = self.ghc.meta.platforms;
-  };
-})
diff --git a/pkgs/development/libraries/haskell/nats/0.2.nix b/pkgs/development/libraries/haskell/nats/0.2.nix
deleted file mode 100644
index e870d171383..00000000000
--- a/pkgs/development/libraries/haskell/nats/0.2.nix
+++ /dev/null
@@ -1,16 +0,0 @@
-# This file was auto-generated by cabal2nix. Please do NOT edit manually!
-
-{ cabal, hashable }:
-
-cabal.mkDerivation (self: {
-  pname = "nats";
-  version = "0.2";
-  sha256 = "05skqs5ahbrnwlsxjihkvmsw0n49k9mqdhrv9nqh4dmd1j622r73";
-  buildDepends = [ hashable ];
-  meta = {
-    homepage = "http://github.com/ekmett/nats/";
-    description = "Natural numbers";
-    license = self.stdenv.lib.licenses.bsd3;
-    platforms = self.ghc.meta.platforms;
-  };
-})
diff --git a/pkgs/development/libraries/haskell/nats/1.nix b/pkgs/development/libraries/haskell/nats/default.nix
similarity index 100%
rename from pkgs/development/libraries/haskell/nats/1.nix
rename to pkgs/development/libraries/haskell/nats/default.nix
diff --git a/pkgs/top-level/haskell-packages.nix b/pkgs/top-level/haskell-packages.nix
index 6c0dda9c20c..5dbc6a5d4dd 100644
--- a/pkgs/top-level/haskell-packages.nix
+++ b/pkgs/top-level/haskell-packages.nix
@@ -55,14 +55,12 @@
 # modifyPrio argument can be set to lowPrio to make all Haskell packages have
 # low priority.
 
-let override = overrides: self_: let
-  self = self_ // overrides;
+self : let callPackage = x : y : modifyPrio (newScope self x y); in
 
-  callPackage = x : y : modifyPrio (newScope self x y);
 # Indentation deliberately broken at this point to keep the bulk
 # of this file at a low indentation level.
 
-in {
+{
   inherit callPackage;
 
   # GHC and its wrapper
@@ -172,34 +170,6 @@ in {
 
   alsaPcm = callPackage ../development/libraries/haskell/alsa-pcm {};
 
-  inherit (let
-    new-transformers-self = if self.overridden or false
-      then self
-      else override {
-        overridden = true;
-
-        mtl = new-transformers-self.mtl_2_2_1;
-
-        transformers = new-transformers-self.transformers_0_4_2_0;
-
-        cabal = new-transformers-self.cabal.override {
-          enableCheckPhase = false;
-        };
-
-        nats = new-transformers-self.nats_0_2;
-      } new-transformers-self;
-
-    inherit (new-transformers-self) callPackage;
-  in {
-      amazonkaCore =
-        callPackage ../development/libraries/haskell/amazonka-core {};
-
-      amazonka = callPackage ../development/libraries/haskell/amazonka {};
-
-      amazonkaCloudwatch =
-        callPackage ../development/libraries/haskell/amazonka-cloudwatch {};
-  }) amazonka amazonkaCore amazonkaCloudwatch;
-
   amqp = callPackage ../development/libraries/haskell/amqp {};
 
   annotatedWlPprint = callPackage ../development/libraries/haskell/annotated-wl-pprint {};
@@ -1859,9 +1829,7 @@ in {
 
   nat = callPackage ../development/libraries/haskell/nat {};
 
-  nats_1 = callPackage ../development/libraries/haskell/nats/1.nix {};
-  nats_0_2 = callPackage ../development/libraries/haskell/nats/0.2.nix {};
-  nats = self.nats_1;
+  nats = callPackage ../development/libraries/haskell/nats {};
 
   naturals = callPackage ../development/libraries/haskell/naturals {};
 
@@ -3291,4 +3259,4 @@ in {
 
 # End of the main part of the file.
 
-}; in override {}
+}