diff --git a/tests/SSL/SSLTest.php b/tests/SSL/SSLTest.php
index 727e6f9..efad60f 100644
--- a/tests/SSL/SSLTest.php
+++ b/tests/SSL/SSLTest.php
@@ -23,29 +23,33 @@ public function setUp() : void
 
     public static function setUpBeforeClass() : void
     {
-        $silence = '>/dev/null 2>&1 & echo $!';
+        $testDir = dirname(__FILE__);
 
-        $commands = [
-            sprintf("php -S %s", PHP_SERVER),
-            sprintf("stunnel3 -d %s -r %s -p %s -P '' -f", GOOD_STUNNEL_SERVER, PHP_SERVER, dirname(__FILE__) . "/" . "good.pem"),
-            sprintf("stunnel3 -d %s -r %s -p %s -P '' -f", SELF_SIGNED_STUNNEL_SERVER, PHP_SERVER, dirname(__FILE__) . "/" . "self.pem"),
-            sprintf("stunnel3 -d %s -r %s -p %s -P '' -f", BAD_HOSTNAME_STUNNEL_SERVER, PHP_SERVER, dirname(__FILE__) . "/" . "badhost.pem"),
-        ];
+        // Use stunnel4 (or stunnel) with config files
+        $stunnelCmd = 'stunnel4';
+        exec('which stunnel4 2>/dev/null', $output, $returnCode);
+        if ($returnCode !== 0) {
+            $stunnelCmd = 'stunnel';
+        }
 
-        $pids = [];
+        // Start PHP server in background
+        $phpServerPid = trim(shell_exec(sprintf("php -S %s >/dev/null 2>&1 & echo \\$!", PHP_SERVER)));
 
-        foreach ($commands as $command) {
-            $output = [];
-            exec($command . $silence, $output);
-            $pid = (int) $output[0];
-            array_push($pids, $pid);
+        // Start stunnel servers using config files (must run from test directory for relative cert paths)
+        $stunnelPids = [];
+        $configs = ['good', 'self', 'badhost'];
+        foreach ($configs as $name) {
+            $pid = trim(shell_exec(sprintf("cd %s && %s stunnel-%s.conf >/dev/null 2>&1 & echo \\$!",
+                $testDir, $stunnelCmd, $name)));
+            $stunnelPids[] = $pid;
         }
 
         // Allow processes to start
         sleep(1);
 
-        register_shutdown_function(function () use ($pids) {
-            foreach ($pids as $pid) {
+        register_shutdown_function(function () use ($phpServerPid, $stunnelPids) {
+            exec('kill ' . $phpServerPid);
+            foreach ($stunnelPids as $pid) {
                 exec('kill ' . $pid);
             }
         });
diff --git a/tests/SSL/stunnel-badhost.conf b/tests/SSL/stunnel-badhost.conf
new file mode 100644
index 0000000..4d8d5d6
--- /dev/null
+++ b/tests/SSL/stunnel-badhost.conf
@@ -0,0 +1,4 @@
+[badhost]
+accept = 4445
+connect = localhost:4000
+cert = badhost.pem
diff --git a/tests/SSL/stunnel-good.conf b/tests/SSL/stunnel-good.conf
new file mode 100644
index 0000000..0ebdb29
--- /dev/null
+++ b/tests/SSL/stunnel-good.conf
@@ -0,0 +1,4 @@
+[good]
+accept = 4443
+connect = localhost:4000
+cert = good.pem
diff --git a/tests/SSL/stunnel-self.conf b/tests/SSL/stunnel-self.conf
new file mode 100644
index 0000000..f4a5ff9
--- /dev/null
+++ b/tests/SSL/stunnel-self.conf
@@ -0,0 +1,4 @@
+[self]
+accept = 4444
+connect = localhost:4000
+cert = self.pem