diff --git a/pkgs/development/tools/build-managers/buildbot/default.nix b/pkgs/development/tools/build-managers/buildbot/default.nix
index b9b8dc71927..ad37aee5bb9 100644
--- a/pkgs/development/tools/build-managers/buildbot/default.nix
+++ b/pkgs/development/tools/build-managers/buildbot/default.nix
@@ -1,76 +1,83 @@
-{ stdenv, lib, fetchurl, coreutils, openssh, buildbot-worker, makeWrapper,
-  pythonPackages, gnused, plugins ? [] }:
+{ stdenv, lib, openssh, buildbot-worker, pythonPackages, runCommand, makeWrapper }:
 
-pythonPackages.buildPythonApplication (rec {
-  name = "${pname}-${version}";
-  pname = "buildbot";
-  version = "0.9.4";
-  src = fetchurl {
-    url = "mirror://pypi/b/${pname}/${name}.tar.gz";
-    sha256 = "0wklrn4fszac9wi8zw3vbsznwyff6y57cz0i81zvh46skb6n3086";
-  };
-
-  buildInputs = with pythonPackages; [
-    lz4
-    txrequests
-    pyjade
-    boto3
-    moto
-    txgithub
-    mock
-    setuptoolsTrial
-    isort
-    pylint
-    astroid
-    pyflakes
-    openssh
-    buildbot-worker
-    makeWrapper
-    treq
-  ];
-
-  propagatedBuildInputs = with pythonPackages; [
-
-    # core
-    twisted
-    jinja2
-    zope_interface
-    sqlalchemy
-    sqlalchemy_migrate
-    future
-    dateutil
-    txaio
-    autobahn
-    pyjwt
-
-    # tls
-    pyopenssl
-    service-identity
-    idna
-
-    # docs
-    sphinx
-    sphinxcontrib-blockdiag
-    sphinxcontrib-spelling
-    pyenchant
-    docutils
-    ramlfications
-    sphinx-jinja
-
-  ] ++ plugins;
-
-  postPatch = ''
-    ${gnused}/bin/sed -i 's|/usr/bin/tail|${coreutils}/bin/tail|' buildbot/scripts/logwatcher.py
+let
+  withPlugins = plugins: runCommand "wrapped-${package.name}" {
+    buildInputs = [ makeWrapper ];
+    passthru.withPlugins = moarPlugins: withPlugins (moarPlugins ++ plugins);
+  } ''
+    makeWrapper ${package}/bin/buildbot $out/bin/buildbot \
+      --prefix PYTHONPATH : ${lib.makeSearchPathOutput "lib" pythonPackages.python.sitePackages plugins}
   '';
 
-  postFixup = ''
-    makeWrapper $out/bin/.buildbot-wrapped $out/bin/buildbot --set PYTHONPATH "$PYTHONPATH"
-  '';
+  package = pythonPackages.buildPythonApplication (rec {
+    name = "${pname}-${version}";
+    pname = "buildbot";
+    version = "0.9.4";
 
-  meta = with stdenv.lib; {
-    homepage = http://buildbot.net/;
-    description = "Continuous integration system that automates the build/test cycle";
-    maintainers = with maintainers; [ nand0p ryansydnor ];
-    license = licenses.gpl2;
-  };
-})
+    src = pythonPackages.fetchPypi {
+      inherit pname version;
+      sha256 = "0wklrn4fszac9wi8zw3vbsznwyff6y57cz0i81zvh46skb6n3086";
+    };
+
+    buildInputs = with pythonPackages; [
+      lz4
+      txrequests
+      pyjade
+      boto3
+      moto
+      txgithub
+      mock
+      setuptoolsTrial
+      isort
+      pylint
+      astroid
+      pyflakes
+      openssh
+      buildbot-worker
+      treq
+    ];
+
+    propagatedBuildInputs = with pythonPackages; [
+
+      # core
+      twisted
+      jinja2
+      zope_interface
+      sqlalchemy
+      sqlalchemy_migrate
+      future
+      dateutil
+      txaio
+      autobahn
+      pyjwt
+
+      # tls
+      pyopenssl
+      service-identity
+      idna
+
+      # docs
+      sphinx
+      sphinxcontrib-blockdiag
+      sphinxcontrib-spelling
+      pyenchant
+      docutils
+      ramlfications
+      sphinx-jinja
+
+    ];
+
+    postPatch = ''
+      substituteInPlace buildbot/scripts/logwatcher.py --replace '/usr/bin/tail' "$(type -P tail)"
+    '';
+
+    passthru = { inherit withPlugins; };
+
+    meta = with stdenv.lib; {
+      homepage = http://buildbot.net/;
+      description = "Continuous integration system that automates the build/test cycle";
+      maintainers = with maintainers; [ nand0p ryansydnor ];
+      license = licenses.gpl2;
+    };
+  });
+in package
diff --git a/pkgs/development/tools/build-managers/buildbot/worker.nix b/pkgs/development/tools/build-managers/buildbot/worker.nix
index 3023555d22c..b9b4b86aa44 100644
--- a/pkgs/development/tools/build-managers/buildbot/worker.nix
+++ b/pkgs/development/tools/build-managers/buildbot/worker.nix
@@ -1,12 +1,12 @@
-{ stdenv, fetchurl, gnused, coreutils, pythonPackages }:
+{ stdenv, pythonPackages }:
 
 pythonPackages.buildPythonApplication (rec {
   name = "${pname}-${version}";
   pname = "buildbot-worker";
   version = "0.9.4";
 
-  src = fetchurl {
-    url = "mirror://pypi/b/${pname}/${name}.tar.gz";
+  src = pythonPackages.fetchPypi {
+    inherit pname version;
     sha256 = "0rdrr8x7sn2nxl51p6h9ad42s3c28lb6sys84zrg0d7fm4zhv7hj";
   };
 
@@ -14,7 +14,7 @@ pythonPackages.buildPythonApplication (rec {
   propagatedBuildInputs = with pythonPackages; [ twisted future ];
 
   postPatch = ''
-    ${gnused}/bin/sed -i 's|/usr/bin/tail|${coreutils}/bin/tail|' buildbot_worker/scripts/logwatcher.py
+    substituteInPlace buildbot_worker/scripts/logwatcher.py --replace '/usr/bin/tail' "$(type -P tail)"
   '';
 
   meta = with stdenv.lib; {
diff --git a/pkgs/top-level/all-packages.nix b/pkgs/top-level/all-packages.nix
index 12504c5099e..a2cc71f0aad 100644
--- a/pkgs/top-level/all-packages.nix
+++ b/pkgs/top-level/all-packages.nix
@@ -6212,12 +6212,8 @@ with pkgs;
   buildbot-plugins = callPackage ../development/tools/build-managers/buildbot/plugins.nix {
     pythonPackages = python2Packages;
   };
-  buildbot-ui = self.buildbot.override {
-    plugins = with self.buildbot-plugins; [ www ];
-  };
-  buildbot-full = self.buildbot.override {
-    plugins = with self.buildbot-plugins; [ www console-view waterfall-view ];
-  };
+  buildbot-ui = buildbot.withPlugins (with self.buildbot-plugins; [ www ]);
+  buildbot-full = buildbot.withPlugins (with self.buildbot-plugins; [ www console-view waterfall-view ]);
 
   buildkite-agent = callPackage ../development/tools/continuous-integration/buildkite-agent { };