diff --git a/tests/clamav.nix b/tests/clamav.nix
index 2600416..ed89857 100644
--- a/tests/clamav.nix
+++ b/tests/clamav.nix
@@ -210,13 +210,8 @@
       server.wait_for_unit("multi-user.target")
       client.wait_for_unit("multi-user.target")
 
-      # TODO put this blocking into the systemd units? I am not sure if rspamd already waits for the clamd socket.
-      server.wait_until_succeeds(
-          "set +e; timeout 1 nc -U /run/rspamd/rspamd-milter.sock < /dev/null; [ $? -eq 124 ]"
-      )
-      server.wait_until_succeeds(
-          "set +e; timeout 1 nc -U /run/clamav/clamd.ctl < /dev/null; [ $? -eq 124 ]"
-      )
+      server.wait_for_open_unix_socket("/run/rspamd/rspamd-milter.sock")
+      server.wait_for_open_unix_socket("/run/clamav/clamd.ctl")
 
       client.execute("cp -p /etc/root/.* ~/")
       client.succeed("mkdir -p ~/mail")
diff --git a/tests/external.nix b/tests/external.nix
index e47013c..40b900a 100644
--- a/tests/external.nix
+++ b/tests/external.nix
@@ -403,10 +403,7 @@
       server.wait_for_unit("multi-user.target")
       client.wait_for_unit("multi-user.target")
 
-      # TODO put this blocking into the systemd units?
-      server.wait_until_succeeds(
-          "set +e; timeout 1 nc -U /run/rspamd/rspamd-milter.sock < /dev/null; [ $? -eq 124 ]"
-      )
+      server.wait_for_open_unix_socket("/run/rspamd/rspamd-milter.sock")
 
       server.succeed("rspamadm dkim_keygen > /run/rspamd/dkim-test.key")
       server.succeed("chown rspamd: /run/rspamd/dkim-test.key")
diff --git a/tests/internal.nix b/tests/internal.nix
index e6c1b17..4fe9bcb 100644
--- a/tests/internal.nix
+++ b/tests/internal.nix
@@ -131,10 +131,7 @@ in
       machine.wait_for_unit("multi-user.target")
       machine.wait_for_unit("dovecot.service")
 
-      # TODO put this blocking into the systemd units?
-      machine.wait_until_succeeds(
-          "set +e; timeout 1 nc -U /run/rspamd/rspamd-milter.sock < /dev/null; [ $? -eq 124 ]"
-      )
+      machine.wait_for_open_unix_socket("/run/rspamd/rspamd-milter.sock")
 
       # Regression test for https://gitlab.com/simple-nixos-mailserver/nixos-mailserver/-/issues/205
       with subtest("mail forwarded can are locally kept"):
diff --git a/tests/ldap.nix b/tests/ldap.nix
index 57e90aa..3a63f53 100644
--- a/tests/ldap.nix
+++ b/tests/ldap.nix
@@ -181,10 +181,7 @@ in
       # if the schema is broken, fail fast. helps during development.
       machine.wait_for_unit("openldap.service")
 
-      # TODO put this blocking into the systemd units?
-      machine.wait_until_succeeds(
-          "set +e; timeout 1 nc -U /run/rspamd/rspamd-milter.sock < /dev/null; [ $? -eq 124 ]"
-      )
+      machine.wait_for_open_unix_socket("/run/rspamd/rspamd-milter.sock")
 
       # This function retrieves the ldap table file from a postconf
       # command.
diff --git a/tests/multiple.nix b/tests/multiple.nix
index d627edd..1b0b04b 100644
--- a/tests/multiple.nix
+++ b/tests/multiple.nix
@@ -99,13 +99,8 @@ in
         domain.wait_for_unit("multi-user.target")
         domain.wait_for_unit("dovecot.service")
 
-      # TODO put this blocking into the systemd units?
-      domain1.wait_until_succeeds(
-          "set +e; timeout 1 nc -U /run/rspamd/rspamd-milter.sock < /dev/null; [ $? -eq 124 ]"
-      )
-      domain2.wait_until_succeeds(
-          "set +e; timeout 1 nc -U /run/rspamd/rspamd-milter.sock < /dev/null; [ $? -eq 124 ]"
-      )
+      for host in [domain1, domain2]:
+        host.wait_for_open_unix_socket("/run/rspamd/rspamd-milter.sock")
 
       # user@domain1.com sends a mail to user@domain2.com via explicit TLS
       client.succeed(