diff --git a/nixos/tests/buildbot.nix b/nixos/tests/buildbot.nix
index f5c8c4863b6f..5655a34a8b51 100644
--- a/nixos/tests/buildbot.nix
+++ b/nixos/tests/buildbot.nix
@@ -1,12 +1,11 @@
+# Test ensures buildbot master comes up correctly and workers can connect
+
 { system ? builtins.currentSystem,
   config ? {},
   pkgs ? import ../.. { inherit system config; }
 }:
 
-with import ../lib/testing.nix { inherit system pkgs; };
-
-# Test ensures buildbot master comes up correctly and workers can connect
-makeTest {
+import ./make-test-python.nix {
   name = "buildbot";
 
   nodes = {
@@ -39,75 +38,76 @@ makeTest {
       services.openssh.enable = true;
       networking.firewall.allowedTCPPorts = [ 22 9418 ];
       environment.systemPackages = with pkgs; [ git ];
+      systemd.services.git-daemon = {
+        description   = "Git daemon for the test";
+        wantedBy      = [ "multi-user.target" ];
+        after         = [ "network.target" ];
+
+        serviceConfig.Restart = "always";
+        path = with pkgs; [ coreutils git openssh ];
+        environment = { HOME = "/root"; };
+        preStart = ''
+          git config --global user.name 'Nobody Fakeuser'
+          git config --global user.email 'nobody\@fakerepo.com'
+          rm -rvf /srv/repos/fakerepo.git /tmp/fakerepo
+          mkdir -pv /srv/repos/fakerepo ~/.ssh
+          ssh-keyscan -H gitrepo > ~/.ssh/known_hosts
+          cat ~/.ssh/known_hosts
+
+          mkdir -p /src/repos/fakerepo
+          cd /srv/repos/fakerepo
+          rm -rf *
+          git init
+          echo -e '#!/bin/sh\necho fakerepo' > fakerepo.sh
+          cat fakerepo.sh
+          touch .git/git-daemon-export-ok
+          git add fakerepo.sh .git/git-daemon-export-ok
+          git commit -m fakerepo
+        '';
+        script = ''
+          git daemon --verbose --export-all --base-path=/srv/repos --reuseaddr
+        '';
+      };
     };
   };
 
   testScript = ''
-    #Start up and populate fake repo
-    $gitrepo->waitForUnit("multi-user.target");
-    print($gitrepo->execute(" \
-      git config --global user.name 'Nobody Fakeuser' && \
-      git config --global user.email 'nobody\@fakerepo.com' && \
-      rm -rvf /srv/repos/fakerepo.git /tmp/fakerepo && \
-      mkdir -pv /srv/repos/fakerepo ~/.ssh && \
-      ssh-keyscan -H gitrepo > ~/.ssh/known_hosts && \
-      cat ~/.ssh/known_hosts && \
-      cd /srv/repos/fakerepo && \
-      git init && \
-      echo -e '#!/bin/sh\necho fakerepo' > fakerepo.sh && \
-      cat fakerepo.sh && \
-      touch .git/git-daemon-export-ok && \
-      git add fakerepo.sh .git/git-daemon-export-ok && \
-      git commit -m fakerepo && \
-      git daemon --verbose --export-all --base-path=/srv/repos --reuseaddr & \
-    "));
+    gitrepo.wait_for_unit("git-daemon.service")
+    gitrepo.wait_for_unit("multi-user.target")
 
-    # Test gitrepo
-    $bbmaster->waitForUnit("network-online.target");
-    #$bbmaster->execute("nc -z gitrepo 9418");
-    print($bbmaster->execute(" \
-      rm -rfv /tmp/fakerepo && \
-      git clone git://gitrepo/fakerepo /tmp/fakerepo && \
-      pwd && \
-      ls -la && \
-      ls -la /tmp/fakerepo \
-    "));
+    with subtest("Repo is accessible via git daemon"):
+        bbmaster.wait_for_unit("network-online.target")
+        bbmaster.succeed("rm -rfv /tmp/fakerepo")
+        bbmaster.succeed("git clone git://gitrepo/fakerepo /tmp/fakerepo")
 
-    # Test start master and connect worker
-    $bbmaster->waitForUnit("buildbot-master.service");
-    $bbmaster->waitUntilSucceeds("curl -s --head http://bbmaster:8010") =~ /200 OK/;
-    $bbworker->waitForUnit("network-online.target");
-    $bbworker->execute("nc -z bbmaster 8010");
-    $bbworker->execute("nc -z bbmaster 9989");
-    $bbworker->waitForUnit("buildbot-worker.service");
-    print($bbworker->execute("ls -la /home/bbworker/worker"));
+    with subtest("Master service and worker successfully connect"):
+        bbmaster.wait_for_unit("buildbot-master.service")
+        bbmaster.wait_until_succeeds("curl --fail -s --head http://bbmaster:8010")
+        bbworker.wait_for_unit("network-online.target")
+        bbworker.succeed("nc -z bbmaster 8010")
+        bbworker.succeed("nc -z bbmaster 9989")
+        bbworker.wait_for_unit("buildbot-worker.service")
 
+    with subtest("Stop buildbot worker"):
+        bbmaster.succeed("systemctl -l --no-pager status buildbot-master")
+        bbmaster.succeed("systemctl stop buildbot-master")
+        bbworker.fail("nc -z bbmaster 8010")
+        bbworker.fail("nc -z bbmaster 9989")
+        bbworker.succeed("systemctl -l --no-pager status buildbot-worker")
+        bbworker.succeed("systemctl stop buildbot-worker")
 
-    # Test stop buildbot master and worker
-    print($bbmaster->execute(" \
-      systemctl -l --no-pager status buildbot-master && \
-      systemctl stop buildbot-master \
-    "));
-    $bbworker->fail("nc -z bbmaster 8010");
-    $bbworker->fail("nc -z bbmaster 9989");
-    print($bbworker->execute(" \
-      systemctl -l --no-pager status buildbot-worker && \
-      systemctl stop buildbot-worker && \
-      ls -la /home/bbworker/worker \
-    "));
-
-
-    # Test buildbot daemon mode
-    $bbmaster->execute("buildbot create-master /tmp");
-    $bbmaster->execute("mv -fv /tmp/master.cfg.sample /tmp/master.cfg");
-    $bbmaster->execute("sed -i 's/8010/8011/' /tmp/master.cfg");
-    $bbmaster->execute("buildbot start /tmp");
-    $bbworker->execute("nc -z bbmaster 8011");
-    $bbworker->waitUntilSucceeds("curl -s --head http://bbmaster:8011") =~ /200 OK/;
-    $bbmaster->execute("buildbot stop /tmp");
-    $bbworker->fail("nc -z bbmaster 8011");
-
+    with subtest("Buildbot daemon mode works"):
+        bbmaster.succeed(
+            "buildbot create-master /tmp",
+            "mv -fv /tmp/master.cfg.sample /tmp/master.cfg",
+            "sed -i 's/8010/8011/' /tmp/master.cfg",
+            "buildbot start /tmp",
+            "nc -z bbmaster 8011",
+        )
+        bbworker.wait_until_succeeds("curl --fail -s --head http://bbmaster:8011")
+        bbmaster.wait_until_succeeds("buildbot stop /tmp")
+        bbworker.fail("nc -z bbmaster 8011")
   '';
 
   meta.maintainers = with pkgs.stdenv.lib.maintainers; [ nand0p ];
-}
+} {}
diff --git a/nixos/tests/ihatemoney.nix b/nixos/tests/ihatemoney.nix
index 14db17fe5e67..7df0ea0b691f 100644
--- a/nixos/tests/ihatemoney.nix
+++ b/nixos/tests/ihatemoney.nix
@@ -1,13 +1,5 @@
-{ system ? builtins.currentSystem
-, config ? {}
-, pkgs ? import ../.. { inherit system config; }
-}:
-
 let
-  inherit (import ../lib/testing.nix { inherit system pkgs; }) makeTest;
-in
-map (
-  backend: makeTest {
+  f = backend: import ./make-test-python.nix ({ pkgs, ... }: {
     name = "ihatemoney-${backend}";
     machine = { lib, ... }: {
       services.ihatemoney = {
@@ -30,23 +22,34 @@ map (
       };
     };
     testScript = ''
-      $machine->waitForOpenPort(8000);
-      $machine->waitForUnit("uwsgi.service");
-      my $return = $machine->succeed("curl -X POST http://localhost:8000/api/projects -d 'name=yay&id=yay&password=yay&contact_email=yay\@example.com'");
-      die "wrong project id $return" unless "\"yay\"\n" eq $return;
-      my $timestamp = $machine->succeed("stat --printf %Y /var/lib/ihatemoney/secret_key");
-      my $owner = $machine->succeed("stat --printf %U:%G /var/lib/ihatemoney/secret_key");
-      die "wrong ownership for the secret key: $owner, is uwsgi running as the right user ?" unless $owner eq "ihatemoney:ihatemoney";
-      $machine->shutdown();
-      $machine->start();
-      $machine->waitForOpenPort(8000);
-      $machine->waitForUnit("uwsgi.service");
-      # check that the database is really persistent
-      print $machine->succeed("curl --basic -u yay:yay http://localhost:8000/api/projects/yay");
-      # check that the secret key is really persistent
-      my $timestamp2 = $machine->succeed("stat --printf %Y /var/lib/ihatemoney/secret_key");
-      die unless $timestamp eq $timestamp2;
-      $machine->succeed("curl http://localhost:8000 | grep ihatemoney");
+      machine.wait_for_open_port(8000)
+      machine.wait_for_unit("uwsgi.service")
+
+      assert '"yay"' in machine.succeed(
+          "curl -X POST http://localhost:8000/api/projects -d 'name=yay&id=yay&password=yay&contact_email=yay\@example.com'"
+      )
+      owner, timestamp = machine.succeed(
+          "stat --printf %U:%G___%Y /var/lib/ihatemoney/secret_key"
+      ).split("___")
+      assert "ihatemoney:ihatemoney" == owner
+
+      with subtest("Restart machine and service"):
+          machine.shutdown()
+          machine.start()
+          machine.wait_for_open_port(8000)
+          machine.wait_for_unit("uwsgi.service")
+
+      with subtest("check that the database is really persistent"):
+          machine.succeed("curl --basic -u yay:yay http://localhost:8000/api/projects/yay")
+
+      with subtest("check that the secret key is really persistent"):
+          timestamp2 = machine.succeed("stat --printf %Y /var/lib/ihatemoney/secret_key")
+          assert timestamp == timestamp2
+
+      assert "ihatemoney" in machine.succeed("curl http://localhost:8000")
     '';
-  }
-) [ "sqlite" "postgresql" ]
+  });
+in {
+  ihatemoney-sqlite = f "sqlite";
+  ihatemoney-postgresql = f "postgresql";
+}
diff --git a/nixos/tests/keymap.nix b/nixos/tests/keymap.nix
index 2b4c1ab7b052..09d5d2a6c9e1 100644
--- a/nixos/tests/keymap.nix
+++ b/nixos/tests/keymap.nix
@@ -3,14 +3,13 @@
   pkgs ? import ../.. { inherit system config; }
 }:
 
-with import ../lib/testing.nix { inherit system pkgs; };
+with import ../lib/testing-python.nix { inherit system pkgs; };
 
 let
   readyFile  = "/tmp/readerReady";
   resultFile = "/tmp/readerResult";
 
   testReader = pkgs.writeScript "test-input-reader" ''
-    #!${pkgs.stdenv.shell}
     rm -f ${resultFile} ${resultFile}.tmp
     logger "testReader: START: Waiting for $1 characters, expecting '$2'."
     touch ${readyFile}
@@ -27,56 +26,75 @@ let
   '';
 
 
-  mkKeyboardTest = layout: { extraConfig ? {}, tests }: with pkgs.lib; let
-    combinedTests = foldAttrs (acc: val: acc ++ val) [] (builtins.attrValues tests);
-    perlStr = val: "'${escape ["'" "\\"] val}'";
-    lq = length combinedTests.qwerty;
-    le = length combinedTests.expect;
-    msg = "length mismatch between qwerty (${toString lq}) and expect (${toString le}) lists!";
-    send   = concatMapStringsSep ", " perlStr combinedTests.qwerty;
-    expect = if (lq == le) then concatStrings combinedTests.expect else throw msg;
-
-  in makeTest {
+  mkKeyboardTest = layout: { extraConfig ? {}, tests }: with pkgs.lib; makeTest {
     name = "keymap-${layout}";
 
+    machine.console.keyMap = mkOverride 900 layout;
     machine.services.xserver.desktopManager.xterm.enable = false;
-    machine.i18n.consoleKeyMap = mkOverride 900 layout;
     machine.services.xserver.layout = mkOverride 900 layout;
     machine.imports = [ ./common/x11.nix extraConfig ];
 
     testScript = ''
+      import json
+      import shlex
 
-      sub mkTest ($$) {
-        my ($desc, $cmd) = @_;
 
-        subtest $desc, sub {
-          # prepare and start testReader
-          $machine->execute("rm -f ${readyFile} ${resultFile}");
-          $machine->succeed("$cmd ${testReader} ${toString le} ".q(${escapeShellArg expect} & ));
+      def run_test_case(cmd, xorg_keymap, test_case_name, inputs, expected):
+          with subtest(test_case_name):
+              assert len(inputs) == len(expected)
+              machine.execute("rm -f ${readyFile} ${resultFile}")
 
-          if ($desc eq "Xorg keymap") {
-            # make sure the xterm window is open and has focus
-            $machine->waitForWindow(qr/testterm/);
-            $machine->waitUntilSucceeds("${pkgs.xdotool}/bin/xdotool search --sync --onlyvisible --class testterm windowfocus --sync");
-          }
+              # set up process that expects all the keys to be entered
+              machine.succeed(
+                  "{} {} {} {} &".format(
+                      cmd,
+                      "${testReader}",
+                      len(inputs),
+                      shlex.quote("".join(expected)),
+                  )
+              )
 
-          # wait for reader to be ready
-          $machine->waitForFile("${readyFile}");
-          $machine->sleep(1);
+              if xorg_keymap:
+                  # make sure the xterm window is open and has focus
+                  machine.wait_for_window("testterm")
+                  machine.wait_until_succeeds(
+                      "${pkgs.xdotool}/bin/xdotool search --sync --onlyvisible "
+                      "--class testterm windowfocus --sync"
+                  )
 
-          # send all keys
-          foreach ((${send})) { $machine->sendKeys($_); };
+              # wait for reader to be ready
+              machine.wait_for_file("${readyFile}")
+              machine.sleep(1)
 
-          # wait for result and check
-          $machine->waitForFile("${resultFile}");
-          $machine->succeed("grep -q 'PASS:' ${resultFile}");
-        };
-      };
+              # send all keys
+              for key in inputs:
+                  machine.send_key(key)
 
-      $machine->waitForX;
+              # wait for result and check
+              machine.wait_for_file("${resultFile}")
+              machine.succeed("grep -q 'PASS:' ${resultFile}")
 
-      mkTest "VT keymap", "openvt -sw --";
-      mkTest "Xorg keymap", "DISPLAY=:0 xterm -title testterm -class testterm -fullscreen -e";
+
+      with open("${pkgs.writeText "tests.json" (builtins.toJSON tests)}") as json_file:
+          tests = json.load(json_file)
+
+      keymap_environments = {
+          "VT Keymap": "openvt -sw --",
+          "Xorg Keymap": "DISPLAY=:0 xterm -title testterm -class testterm -fullscreen -e",
+      }
+
+      machine.wait_for_x()
+
+      for keymap_env_name, command in keymap_environments.items():
+          with subtest(keymap_env_name):
+              for test_case_name, test_data in tests.items():
+                  run_test_case(
+                      command,
+                      False,
+                      test_case_name,
+                      test_data["qwerty"],
+                      test_data["expect"],
+                  )
     '';
   };
 
@@ -89,7 +107,7 @@ in pkgs.lib.mapAttrs mkKeyboardTest {
       altgr.expect = [ "~"       "#"       "{"       "["       "|"       ];
     };
 
-    extraConfig.i18n.consoleKeyMap = "azerty/fr";
+    extraConfig.console.keyMap = "azerty/fr";
     extraConfig.services.xserver.layout = "fr";
   };
 
@@ -99,7 +117,7 @@ in pkgs.lib.mapAttrs mkKeyboardTest {
       homerow.expect = [ "a" "r" "s" "t" "n" "e" "i" "o"         ];
     };
 
-    extraConfig.i18n.consoleKeyMap = "colemak/colemak";
+    extraConfig.console.keyMap = "colemak/colemak";
     extraConfig.services.xserver.layout = "us";
     extraConfig.services.xserver.xkbVariant = "colemak";
   };
@@ -151,7 +169,7 @@ in pkgs.lib.mapAttrs mkKeyboardTest {
       altgr.expect = [ "@" "|"    "{" "[" "]" "}" ];
     };
 
-    extraConfig.i18n.consoleKeyMap = "de";
+    extraConfig.console.keyMap = "de";
     extraConfig.services.xserver.layout = "de";
   };
 }