diff --git a/default.nix b/default.nix
index c3773ff..35f0ee9 100644
--- a/default.nix
+++ b/default.nix
@@ -1,9 +1,9 @@
-{ compiler ? "ghc865" }:
+{ compiler ? "ghc8107" }:
 
 let
   nixpkgs = builtins.fetchTarball {
-    url    = "https://github.com/NixOS/nixpkgs/archive/ae66c3e40486c0e88a6cefc8d275c248fc6a696c.tar.gz";
-    sha256 = "1gw4kdlkmxyil8capnagv41hqmh31hkibidjgy3bxhlljr8xgfkc";
+    url    = "https://github.com/NixOS/nixpkgs/archive/391f93a83c3a486475d60eb4a569bb6afbf306ad.tar.gz";
+    sha256 = "0s5f7j2akh3g0013880jfbigdaac1z76r9dv46yw6k254ba2r6nq";
   };
 
   config = {};
@@ -19,8 +19,6 @@ let
               };
 
               manualOverrides = haskellPackagesNew: haskellPackagesOld: {
-                optparse-applicative =
-                  haskellPackagesNew.optparse-applicative_0_16_1_0;
               };
 
               default = old.overrides or (_: _: {});
diff --git a/optparse-applicative.nix b/optparse-applicative.nix
deleted file mode 100644
index c2b0528..0000000
--- a/optparse-applicative.nix
+++ /dev/null
@@ -1,15 +0,0 @@
-{ mkDerivation, ansi-wl-pprint, base, bytestring, process
-, QuickCheck, stdenv, transformers, transformers-compat
-}:
-mkDerivation {
-  pname = "optparse-applicative";
-  version = "0.16.0.0";
-  sha256 = "09c53c339c41167701343afaeccd5993c6bd827290a2b30053f2a7375555cb2b";
-  libraryHaskellDepends = [
-    ansi-wl-pprint base process transformers transformers-compat
-  ];
-  testHaskellDepends = [ base bytestring QuickCheck ];
-  homepage = "https://github.com/pcapriotti/optparse-applicative";
-  description = "Utilities and combinators for parsing command line options";
-  license = stdenv.lib.licenses.bsd3;
-}
diff --git a/turtle.cabal b/turtle.cabal
index 853620a..f8856e7 100644
--- a/turtle.cabal
+++ b/turtle.cabal
@@ -112,7 +112,7 @@ test-suite tests
     Default-Language: Haskell2010
     Build-Depends:
         base    >= 4   && < 5   ,
-        doctest >= 0.7 && < 0.19
+        doctest >= 0.7
 
 test-suite regression-broken-pipe
     Type: exitcode-stdio-1.0