diff --git a/nixos/tests/lxqt.nix b/nixos/tests/lxqt.nix
index 99b507ff28a3..595b6dc3f9ba 100644
--- a/nixos/tests/lxqt.nix
+++ b/nixos/tests/lxqt.nix
@@ -37,7 +37,7 @@
       with subtest("Wait for login"):
           machine.wait_for_x()
           machine.wait_for_file("/tmp/xauth_*")
-          machine.sleep(1)
+          machine.wait_until_succeeds("test -s /tmp/xauth_*")
           machine.succeed("xauth merge /tmp/xauth_*")
           machine.succeed("su - ${user.name} -c 'xauth merge /tmp/xauth_*'")
 
diff --git a/nixos/tests/maestral.nix b/nixos/tests/maestral.nix
index 57e07b7e76f8..6432ab73b4f5 100644
--- a/nixos/tests/maestral.nix
+++ b/nixos/tests/maestral.nix
@@ -71,7 +71,7 @@
       with subtest("GUI"):
         gui.wait_for_x()
         gui.wait_for_file("/run/user/1000/xauth_*")
-        gui.sleep(1)
+        gui.wait_until_succeeds("test -s /run/user/1000/xauth_*")
         gui.succeed("xauth merge /run/user/1000/xauth_*")
         gui.wait_for_window("^Desktop ")
         gui.wait_for_unit("maestral.service", "${user.name}")
diff --git a/nixos/tests/plasma6.nix b/nixos/tests/plasma6.nix
index 5b350ef54382..7e74f3219eaa 100644
--- a/nixos/tests/plasma6.nix
+++ b/nixos/tests/plasma6.nix
@@ -33,7 +33,7 @@
       with subtest("Wait for login"):
           start_all()
           machine.wait_for_file("/run/user/1000/xauth_*")
-          machine.sleep(1)
+          machine.wait_until_succeeds("test -s /run/user/1000/xauth_*")
           machine.succeed("xauth merge /run/user/1000/xauth_*")
           machine.succeed("su - ${user.name} -c 'xauth merge /run/user/1000/xauth_*'")
 
diff --git a/nixos/tests/retroarch.nix b/nixos/tests/retroarch.nix
index 4d813cc10b05..5f4fe101b46d 100644
--- a/nixos/tests/retroarch.nix
+++ b/nixos/tests/retroarch.nix
@@ -36,7 +36,7 @@
       with subtest("Wait for login"):
           start_all()
           machine.wait_for_file("/run/sddm/xauth_*")
-          machine.sleep(1)
+          machine.wait_until_succeeds("test -s /run/sddm/xauth_*")
           machine.succeed("xauth merge /run/sddm/xauth_*")
 
       with subtest("Check RetroArch started"):
diff --git a/nixos/tests/sddm.nix b/nixos/tests/sddm.nix
index 014c8d379748..4a3b1321b7d6 100644
--- a/nixos/tests/sddm.nix
+++ b/nixos/tests/sddm.nix
@@ -24,7 +24,7 @@
         machine.screenshot("sddm")
         machine.send_chars("${user.password}\n")
         machine.wait_for_file("/tmp/xauth_*")
-        machine.sleep(1)
+        machine.wait_until_succeeds("test -s /tmp/xauth_*")
         machine.succeed("xauth merge /tmp/xauth_*")
         machine.wait_for_window("^IceWM ")
       '';
@@ -55,7 +55,7 @@
       testScript = ''
         start_all()
         machine.wait_for_file("/tmp/xauth_*")
-        machine.sleep(1)
+        machine.wait_until_succeeds("test -s /tmp/xauth_*")
         machine.succeed("xauth merge /tmp/xauth_*")
         machine.wait_for_window("^IceWM ")
       '';