diff --git a/.github/workflows/tests-all.yml b/.github/workflows/tests-all.yml
index 2b08a32..8ee76c5 100644
--- a/.github/workflows/tests-all.yml
+++ b/.github/workflows/tests-all.yml
@@ -6,7 +6,5 @@ jobs:
     steps:
       - uses: actions/checkout@v4
       - run: sudo apt update
-      - run: sudo apt install pycodestyle pyflakes3
-      - run: ./run_tests checks
-      - run: sudo apt install python3-mock
-      - run: ./run_tests unittests
+      - run: sudo apt install cmdtest figlet python3-flask-restful python3-pexpect python3-aiosmtpd
+      - run: ./run_tests stubs smtpd
diff --git a/stubs/cmdtests/smtpd.script b/stubs/cmdtests/smtpd.script
index 7eda1e5..2384dcf 100755
--- a/stubs/cmdtests/smtpd.script
+++ b/stubs/cmdtests/smtpd.script
@@ -33,7 +33,6 @@
 
 import os
 import os.path
-import sys
 import subprocess
 import time
 
@@ -43,6 +42,9 @@ def main():
       stubdir = os.path.join(srcdir, 'stubs')
       smtpddir = os.path.join(datadir, 'smtpddir')
 
+      port = 4433
+      delay = 5
+
       os.chdir(datadir)
 
       os.mkdir(smtpddir)
@@ -50,15 +52,25 @@ def main():
       env = os.environ.copy()
       env['STUB_SMTPD_DATADIR'] = smtpddir
 
-      smtpd = subprocess.Popen([os.path.join(stubdir, 'smtpd'), '--port=4321'],
+      print('Starting smtpd on port %d' % (port))
+      smtpd = subprocess.Popen([os.path.join(stubdir, 'smtpd'), '--port=%d' % (port)],
                                env=env)
 
-      time.sleep(1)
+      (stdout, stderr) = smtpd.communicate()
+      print('smtpd.returncode:' % (smtpd.returncode))
+      print(stdout)
+      print(stderr)
+
+      print('Sleeping %ds' % (delay))
+      time.sleep(delay)
 
-      subprocess.call([os.path.join(stubdir, 'smtpclient'), '--port=4321'])
+      print('Starting smtpclient on port %d' % (port))
+      subprocess.call([os.path.join(stubdir, 'smtpclient'), '--port=%d' % (port)])
 
-      time.sleep(1)
+      print('Sleeping %ds' % (delay))
+      time.sleep(delay)
 
+      print('Killing smtpd')
       smtpd.kill()
 
       # print all the files to make sure there are no extra mails
diff --git a/stubs/cmdtests/smtpd.stdout b/stubs/cmdtests/smtpd.stdout
index d9cc387..25df4b0 100644
--- a/stubs/cmdtests/smtpd.stdout
+++ b/stubs/cmdtests/smtpd.stdout
@@ -1,3 +1,8 @@
+Starting smtpd on port 4433
+Sleeping 5s
+Starting smtpclient on port 4433
+Sleeping 5s
+Killing smtpd
 files: ['0']
 test@example.com -> foo@example.com, bar@example.com
 Content-Type: text/plain; charset="us-ascii"
diff --git a/stubs/smtpclient b/stubs/smtpclient
index e1da9dc..b4dd833 100755
--- a/stubs/smtpclient
+++ b/stubs/smtpclient
@@ -47,7 +47,7 @@ def run(args):
     msg['From'] = from_address
 
     try:
-        server = smtplib.SMTP('localhost', args.port)
+        server = smtplib.SMTP('127.0.0.1', args.port)
         server.sendmail(from_address, to, msg.as_string())
         server.quit()
     except Exception as e: