diff --git a/pkgs/development/libraries/fftw/default.nix b/pkgs/development/libraries/fftw/default.nix
index 7f4188208ff..37a7f1ce8fe 100644
--- a/pkgs/development/libraries/fftw/default.nix
+++ b/pkgs/development/libraries/fftw/default.nix
@@ -3,7 +3,7 @@
 , lib
 , gfortran
 , perl
-, llvmPackages
+, llvmPackages ? null
 , precision ? "double"
 , enableAvx ? stdenv.hostPlatform.avxSupport
 , enableAvx2 ? stdenv.hostPlatform.avx2Support
@@ -11,50 +11,56 @@
 , enableFma ? stdenv.hostPlatform.fmaSupport
 , enableMpi ? false
 , mpi
-, withDoc ? stdenv.cc.isGNU
 }:
 
+with lib;
 
-assert lib.elem precision [ "single" "double" "long-double" "quad-precision" ];
+assert stdenv.cc.isClang -> llvmPackages != null;
+assert elem precision [ "single" "double" "long-double" "quad-precision" ];
 
-stdenv.mkDerivation rec {
-  pname = "fftw-${precision}";
+let
   version = "3.3.9";
+  withDoc = stdenv.cc.isGNU;
+in
+
+stdenv.mkDerivation {
+  name = "fftw-${precision}-${version}";
 
   src = fetchurl {
     urls = [
-      "https://fftw.org/fftw-${version}.tar.gz"
+      "http://fftw.org/fftw-${version}.tar.gz"
       "ftp://ftp.fftw.org/pub/fftw/fftw-${version}.tar.gz"
     ];
     sha256 = "sha256-vyx85AsEroEa9xTetRJRDMLBe5q51t3PSf5Eh+6nrz0=";
   };
 
   outputs = [ "out" "dev" "man" ]
-    ++ lib.optional withDoc "info"; # it's dev-doc only
+    ++ optional withDoc "info"; # it's dev-doc only
   outputBin = "dev"; # fftw-wisdom
 
   nativeBuildInputs = [ gfortran ];
 
-  buildInputs = lib.optionals stdenv.cc.isClang [
+  buildInputs = optionals stdenv.cc.isClang [
     # TODO: This may mismatch the LLVM version sin the stdenv, see #79818.
     llvmPackages.openmp
-  ] ++ lib.optional enableMpi mpi;
+  ] ++ optional enableMpi mpi;
 
-  configureFlags = [
-    "--enable-shared"
-    "--enable-threads"
-    "--enable-openmp"
-  ] ++ lib.optional (precision != "double") "--enable-${precision}"
+  configureFlags =
+    [ "--enable-shared"
+      "--enable-threads"
+    ]
+    ++ optional (precision != "double") "--enable-${precision}"
     # all x86_64 have sse2
     # however, not all float sizes fit
-    ++ lib.optional (stdenv.isx86_64 && (precision == "single" || precision == "double") )  "--enable-sse2"
-    ++ lib.optional enableAvx "--enable-avx"
-    ++ lib.optional enableAvx2 "--enable-avx2"
-    ++ lib.optional enableAvx512 "--enable-avx512"
-    ++ lib.optional enableFma "--enable-fma"
-    ++ lib.optional enableMpi "--enable-mpi"
+    ++ optional (stdenv.isx86_64 && (precision == "single" || precision == "double") )  "--enable-sse2"
+    ++ optional enableAvx "--enable-avx"
+    ++ optional enableAvx2 "--enable-avx2"
+    ++ optional enableAvx512 "--enable-avx512"
+    ++ optional enableFma "--enable-fma"
+    ++ [ "--enable-openmp" ]
+    ++ optional enableMpi "--enable-mpi"
     # doc generation causes Fortran wrapper generation which hard-codes gcc
-    ++ lib.optional (!withDoc) "--disable-doc";
+    ++ optional (!withDoc) "--disable-doc";
 
   enableParallelBuilding = true;
 
diff --git a/pkgs/development/libraries/stfl/default.nix b/pkgs/development/libraries/stfl/default.nix
index 56b97235b0c..20676c16b9c 100644
--- a/pkgs/development/libraries/stfl/default.nix
+++ b/pkgs/development/libraries/stfl/default.nix
@@ -10,11 +10,13 @@ stdenv.mkDerivation rec {
 
   buildInputs = [ ncurses libiconv ];
 
-  preBuild = ''
+  buildPhase = ''
     sed -i s/gcc/cc/g Makefile
     sed -i s%ncursesw/ncurses.h%ncurses.h% stfl_internals.h
-  '' + lib.optionalString stdenv.isDarwin ''
+  '' + ( lib.optionalString stdenv.isDarwin ''
     sed -i s/-soname/-install_name/ Makefile
+  '' ) + ''
+    make
   '';
 
   installPhase = ''
@@ -24,11 +26,11 @@ stdenv.mkDerivation rec {
     ln -s $out/lib/libstfl.so.0.24 $out/lib/libstfl.so.0
   '';
 
-  meta = with lib; {
+  meta = {
     homepage    = "http://www.clifford.at/stfl/";
     description = "A library which implements a curses-based widget set for text terminals";
-    maintainers = with maintainers; [ lovek323 ];
-    license     = licenses.lgpl3;
-    platforms   = platforms.unix;
+    maintainers = with lib.maintainers; [ lovek323 ];
+    license     = lib.licenses.lgpl3;
+    platforms   = lib.platforms.unix;
   };
 }
diff --git a/pkgs/development/libraries/telepathy/qt/default.nix b/pkgs/development/libraries/telepathy/qt/default.nix
index f11759b01f5..dbbaca7e11a 100644
--- a/pkgs/development/libraries/telepathy/qt/default.nix
+++ b/pkgs/development/libraries/telepathy/qt/default.nix
@@ -1,19 +1,20 @@
-{ lib, stdenv, fetchurl, cmake, qtbase, pkg-config, python3, dbus-glib, dbus
+{ lib, stdenv, fetchurl, cmake, qtbase, pkg-config, python3Packages, dbus-glib, dbus
 , telepathy-farstream, telepathy-glib }:
 
-stdenv.mkDerivation rec {
-  pname = "telepathy-qt";
-  version = "0.9.8";
+let
+  inherit (python3Packages) python dbus-python;
+in stdenv.mkDerivation rec {
+  name = "telepathy-qt-0.9.8";
 
   src = fetchurl {
-    url = "https://telepathy.freedesktop.org/releases/telepathy-qt/telepathy-qt-${version}.tar.gz";
+    url = "https://telepathy.freedesktop.org/releases/telepathy-qt/${name}.tar.gz";
     sha256 = "bf8e2a09060addb80475a4938105b9b41d9e6837999b7a00e5351783857e18ad";
   };
 
-  nativeBuildInputs = [ cmake pkg-config python3 ];
+  nativeBuildInputs = [ cmake pkg-config python ];
   propagatedBuildInputs = [ qtbase telepathy-farstream telepathy-glib ];
   buildInputs = [ dbus-glib ];
-  checkInputs = [ dbus.daemon python3.pkgs.dbus-python ];
+  checkInputs = [ dbus.daemon dbus-python ];
 
   # No point in building tests if they are not run
   # On 0.9.7, they do not even build with QT4
@@ -28,6 +29,5 @@ stdenv.mkDerivation rec {
     homepage = "https://telepathy.freedesktop.org/components/telepathy-qt/";
     license = licenses.lgpl21;
     platforms = platforms.linux;
-    maintainers = with maintainers; [ ];
   };
 }
diff --git a/pkgs/development/libraries/tokyo-tyrant/default.nix b/pkgs/development/libraries/tokyo-tyrant/default.nix
index 879666f2490..6431e6a1a7a 100644
--- a/pkgs/development/libraries/tokyo-tyrant/default.nix
+++ b/pkgs/development/libraries/tokyo-tyrant/default.nix
@@ -11,27 +11,31 @@ stdenv.mkDerivation rec {
   nativeBuildInputs = [ pkg-config ];
   buildInputs = [ tokyocabinet ];
 
-  doCheck = false; # FIXME
+  doCheck = false;                                # FIXME
 
-  meta = with lib; {
+  meta = {
     description = "Network interface of the Tokyo Cabinet DBM";
-    longDescription = ''
-      Tokyo Tyrant is a package of network interface to the DBM called
-      Tokyo Cabinet.  Though the DBM has high performance, you might
-      bother in case that multiple processes share the same database, or
-      remote processes access the database.  Thus, Tokyo Tyrant is
-      provided for concurrent and remote connections to Tokyo Cabinet.  It
-      is composed of the server process managing a database and its access
-      library for client applications.
 
-      Tokyo Tyrant is written in the C language, and provided as API of C,
-      Perl, and Ruby.  Tokyo Tyrant is available on platforms which have
-      API conforming to C99 and POSIX.  Tokyo Tyrant is a free software
-      licensed under the GNU Lesser General Public License.
-    '';
+    longDescription =
+      '' Tokyo Tyrant is a package of network interface to the DBM called
+         Tokyo Cabinet.  Though the DBM has high performance, you might
+         bother in case that multiple processes share the same database, or
+         remote processes access the database.  Thus, Tokyo Tyrant is
+         provided for concurrent and remote connections to Tokyo Cabinet.  It
+         is composed of the server process managing a database and its access
+         library for client applications.
+
+         Tokyo Tyrant is written in the C language, and provided as API of C,
+         Perl, and Ruby.  Tokyo Tyrant is available on platforms which have
+         API conforming to C99 and POSIX.  Tokyo Tyrant is a free software
+         licensed under the GNU Lesser General Public License.
+       '';
+
     homepage = "https://fallabs.com/tokyotyrant/";
-    license = licenses.lgpl21Plus;
-    platforms = platforms.linux;
-    maintainers = with maintainers; [ ];
+
+    license = lib.licenses.lgpl21Plus;
+
+    platforms = lib.platforms.gnu ++ lib.platforms.linux;         # arbitrary choice
+    maintainers = [ ];
   };
 }
diff --git a/pkgs/development/tools/iaca/3.0.nix b/pkgs/development/tools/iaca/3.0.nix
index b1bdbd6da86..731b6431717 100644
--- a/pkgs/development/tools/iaca/3.0.nix
+++ b/pkgs/development/tools/iaca/3.0.nix
@@ -1,24 +1,20 @@
 { lib, stdenv, requireFile, unzip }:
+with lib;
 
 stdenv.mkDerivation {
-  pname = "iaca";
-  version = "3.0";
-
+  name = "iaca-3.0";
   src = requireFile {
     name = "iaca-version-v3.0-lin64.zip";
     sha256 = "0qd81bxg269cwwvfmdp266kvhcl3sdvhrkfqdrbmanawk0w7lvp1";
     url = "https://software.intel.com/en-us/articles/intel-architecture-code-analyzer-download";
   };
-
   unpackCmd = ''${unzip}/bin/unzip "$src"'';
-
   installPhase = ''
     mkdir -p $out/bin
     cp iaca $out/bin
     patchelf --set-interpreter ${stdenv.glibc}/lib/ld-linux-x86-64.so.2 $out/bin/iaca
   '';
-
-  meta = with lib; {
+  meta = {
     description = "Intel Architecture Code Analyzer";
     homepage = "https://software.intel.com/en-us/articles/intel-architecture-code-analyzer/";
     license = licenses.unfree;
diff --git a/pkgs/os-specific/darwin/maloader/default.nix b/pkgs/os-specific/darwin/maloader/default.nix
index d860ac38bce..9142484e043 100644
--- a/pkgs/os-specific/darwin/maloader/default.nix
+++ b/pkgs/os-specific/darwin/maloader/default.nix
@@ -1,12 +1,10 @@
-{ lib, stdenv, fetchFromGitHub, opencflite, clang, libcxx }:
+{ lib, stdenv, fetchgit, opencflite, clang, libcxx }:
 
 stdenv.mkDerivation {
-  pname = "maloader";
-  version = "unstable-2014-02-25";
+  name = "maloader-0git";
 
-  src = fetchFromGitHub {
-    owner = "shinh";
-    repo = "maloader";
+  src = fetchgit {
+    url = "git://github.com/shinh/maloader.git";
     rev = "5f220393e0b7b9ad0cf1aba0e89df2b42a1f0442";
     sha256 = "0dd1pn07x1y8pyn5wz8qcl1c1xwghyya4d060m3y9vx5dhv9xmzw";
   };
@@ -30,12 +28,11 @@ stdenv.mkDerivation {
     done
   '';
 
-  meta = with lib; {
+  meta = {
     description = "Mach-O loader for Linux";
     homepage = "https://github.com/shinh/maloader";
-    license = licenses.bsd2;
-    platforms = platforms.linux;
-    maintainers = with maintainers; [ ];
+    license = lib.licenses.bsd2;
+    platforms = lib.platforms.linux;
     broken = true; # 2018-09-08, no succesful build since 2017-08-21
   };
 }