diff --git a/test/tool/net/redbean_test.c b/test/tool/net/redbean_test.c
index e13c3cfdd..06996f0d0 100644
--- a/test/tool/net/redbean_test.c
+++ b/test/tool/net/redbean_test.c
@@ -291,3 +291,45 @@ Z\n",
   EXPECT_NE(-1, wait(0));
   EXPECT_NE(-1, sigprocmask(SIG_SETMASK, &savemask, 0));
 }
+
+TEST(redbean, testWebSockets) {
+  if (IsWindows())
+    return;
+  char portbuf[16];
+  int pid, pipefds[2];
+  sigset_t chldmask, savemask;
+  sigaddset(&chldmask, SIGCHLD);
+  EXPECT_NE(-1, sigprocmask(SIG_BLOCK, &chldmask, &savemask));
+  ASSERT_NE(-1, pipe(pipefds));
+  ASSERT_NE(-1, (pid = fork()));
+  if (!pid) {
+    setpgrp();
+    close(0);
+    open("/dev/null", O_RDWR);
+    close(pipefds[0]);
+    dup2(pipefds[1], 1);
+    sigprocmask(SIG_SETMASK, &savemask, NULL);
+    execv("bin/redbean-tester",
+          (char *const[]){"bin/redbean-tester", "-vvszXp0", "-l127.0.0.1", // "-L/tmp/redbean-tester.log",
+                          __strace > 0 ? "--strace" : 0, 0});
+    _exit(127);
+  }
+  EXPECT_NE(-1, close(pipefds[1]));
+  EXPECT_NE(-1, read(pipefds[0], portbuf, sizeof(portbuf)));
+  port = atoi(portbuf);
+  EXPECT_TRUE(Matches("HTTP/1.1 101 Switching Protocols\r\n"
+                      "Upgrade: websocket\r\n"
+                      "Connection: Upgrade\r\n"
+                      "Sec-WebSocket-Accept: s3pPLMBiTxaQ9kYGzzhZRbK+xOo=\r\n"
+                      "Date: .*\r\n"
+                      "Server: redbean/.*\r\n"
+                      "\r\n",
+                      gc(SendHttpRequest("GET /ws HTTP/1.1\r\n"
+                                         "Upgrade: websocket\r\n"
+                                         "Connection: Upgrade\r\n"
+                                         "Sec-WebSocket-Key: dGhlIHNhbXBsZSBub25jZQ==\r\n\r\n"))));
+  EXPECT_EQ(0, close(pipefds[0]));
+  EXPECT_NE(-1, kill(pid, SIGTERM));
+  EXPECT_NE(-1, wait(0));
+  EXPECT_NE(-1, sigprocmask(SIG_SETMASK, &savemask, 0));
+}
diff --git a/tool/net/tester/.init.lua b/tool/net/tester/.init.lua
index 6fa68a912..ccdd769fa 100644
--- a/tool/net/tester/.init.lua
+++ b/tool/net/tester/.init.lua
@@ -10,10 +10,14 @@ function OnHttpRequest()
     ws.Write(nil) -- upgrade without sending a response
     coroutine.yield()
 
-    local fds = {[GetClientFd()] = unix.POLLIN}
+    local fd = GetClientFd()
+    local fds = {[fd] = unix.POLLIN | unix.POLLHUP | unix.POLLRDHUP}
     -- simple echo server
     while true do
-      unix.poll(fds)
+      res = unix.poll(fds)
+      if (res[fd] & unix.POLLHUP == unix.POLLHUP) or (res[fd] & unix.POLLRDHUP == unix.POLLRDHUP) then
+        return
+      end
       local s, t = ws.Read()
       if t == ws.CLOSE then
         return