diff --git a/tests/conftest.py b/tests/conftest.py
index 7ce08966..189971b1 100644
--- a/tests/conftest.py
+++ b/tests/conftest.py
@@ -4,9 +4,9 @@ import os
 import socket
 import ssl
 import sys
+from itertools import count
 from pathlib import Path
 
-import ephemeral_port_reserve
 import pytest
 from xprocess import ProcessStarter
 
@@ -15,6 +15,24 @@ from werkzeug.utils import cached_property
 run_path = str(Path(__file__).parent / "live_apps" / "run.py")
 
 
+def get_free_port():
+    gen_port = count(49152)
+    s = socket.socket()
+    s.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
+
+    while True:
+        port = next(gen_port)
+
+        try:
+            s.bind(("127.0.0.1", port))
+        except OSError:
+            continue
+
+        s.close()
+        return port
+
+
+
 class UnixSocketHTTPConnection(http.client.HTTPConnection):
     def connect(self):
         self.sock = socket.socket(socket.AF_UNIX, socket.SOCK_STREAM)
@@ -29,7 +47,7 @@ class DevServerClient:
             port = kwargs.get("port")
 
             if port is None:
-                kwargs["port"] = port = ephemeral_port_reserve.reserve(host)
+                kwargs["port"] = port = port = get_free_port()
 
             scheme = "https" if "ssl_context" in kwargs else "http"
             self.addr = f"{host}:{port}"