diff --git a/src/include/microhttpd2.h b/src/include/microhttpd2.h
index 77df726c..4412179d 100644
--- a/src/include/microhttpd2.h
+++ b/src/include/microhttpd2.h
@@ -5332,7 +5332,7 @@ MHD_FN_PAR_NONNULL_ALL_;
 MHD_EXTERN_ const struct MHD_Action *
 MHD_action_from_response (struct MHD_Request *MHD_RESTRICT request,
                           struct MHD_Response *MHD_RESTRICT response)
-MHD_FN_PAR_NONNULL_(1);
+MHD_FN_PAR_NONNULL_ (1);
 
 
 /**
@@ -5900,7 +5900,7 @@ MHD_FN_RETURNS_NONNULL_ MHD_FN_PAR_NONNULL_ALL_;
 MHD_EXTERN_ const struct MHD_UploadAction *
 MHD_upload_action_from_response (struct MHD_Request *MHD_RESTRICT request,
                                  struct MHD_Response *MHD_RESTRICT response)
-MHD_FN_PAR_NONNULL_(1);
+MHD_FN_PAR_NONNULL_ (1);
 
 /**
  * Action telling MHD to continue processing the upload.
diff --git a/src/tests/basic/libtest.h b/src/tests/basic/libtest.h
index 2dcc65be..49bbf9e8 100644
--- a/src/tests/basic/libtest.h
+++ b/src/tests/basic/libtest.h
@@ -319,7 +319,9 @@ typedef void
  * simple #MHD_daemon_start() method until
  * a read() against @a finsig succeeds.
  *
- * @param cls closure
+ * @param cls closure, pass a NULL-terminated (!)
+ *   array of `struct MHD_DaemonOptionAndValue` with the
+ *   the threading mode to use
  * @param finsig fd to read from to detect termination request
  * @param[in,out] d daemon to run
  */
diff --git a/src/tests/basic/libtest_convenience.c b/src/tests/basic/libtest_convenience.c
index 50f5416e..77dcb557 100644
--- a/src/tests/basic/libtest_convenience.c
+++ b/src/tests/basic/libtest_convenience.c
@@ -37,11 +37,19 @@ const char *
 MHDT_server_setup_minimal (void *cls,
                            struct MHD_Daemon *d)
 {
+  const struct MHD_DaemonOptionAndValue *options = cls;
+
+  if (MHD_SC_OK !=
+      MHD_daemon_set_options (
+        d,
+        options,
+        MHD_OPTIONS_ARRAY_MAX_SIZE))
+    return "Failed to configure threading mode!";
+  return NULL;
+
   if (MHD_SC_OK !=
       MHD_DAEMON_SET_OPTIONS (
         d,
-        MHD_D_OPTION_POLL_SYSCALL (MHD_SPS_POLL),
-        MHD_D_OPTION_WM_WORKER_THREADS (1),
         MHD_D_OPTION_BIND_PORT (MHD_AF_AUTO,
                                 0)))
     return "Failed to bind to port 0!";
@@ -90,7 +98,6 @@ MHDT_server_run_minimal (void *cls,
 }
 
 
-#if FUTURE
 void
 MHDT_server_run_blocking (void *cls,
                           int finsig,
@@ -120,7 +127,7 @@ MHDT_server_run_blocking (void *cls,
                strerror (errno));
       break;
     }
-
+#if FIXME
     if (MHD_SC_OK !=
         MHD_daemon_process_blocking (d,
                                      1000))
@@ -129,6 +136,9 @@ MHDT_server_run_blocking (void *cls,
                "Failure running MHD_daemon_process_blocking()\n");
       break;
     }
+#else
+    abort ();
+#endif
   }
   if ( (FD_ISSET (finsig,
                   &r)) &&
@@ -140,6 +150,3 @@ MHDT_server_run_blocking (void *cls,
              "Failed to drain termination signal\n");
   }
 }
-
-
-#endif
diff --git a/src/tests/basic/test_client_server.c b/src/tests/basic/test_client_server.c
index c4a54fd3..269559c6 100644
--- a/src/tests/basic/test_client_server.c
+++ b/src/tests/basic/test_client_server.c
@@ -24,12 +24,124 @@
  * @author Christian Grothoff
  */
 #include <microhttpd2.h>
+#include "mhd_config.h"
 #include "libtest.h"
 
 
 int
 main (int argc, char *argv[])
 {
+  struct MHD_DaemonOptionAndValue thread1select[] = {
+    MHD_D_OPTION_POLL_SYSCALL (MHD_SPS_SELECT),
+    MHD_D_OPTION_WM_WORKER_THREADS (1),
+    MHD_D_OPTION_TERMINATE ()
+  };
+  struct MHD_DaemonOptionAndValue thread2select[] = {
+    MHD_D_OPTION_POLL_SYSCALL (MHD_SPS_SELECT),
+    MHD_D_OPTION_WM_WORKER_THREADS (2),
+    MHD_D_OPTION_TERMINATE ()
+  };
+  struct MHD_DaemonOptionAndValue thread1poll[] = {
+    MHD_D_OPTION_POLL_SYSCALL (MHD_SPS_POLL),
+    MHD_D_OPTION_WM_WORKER_THREADS (1),
+    MHD_D_OPTION_TERMINATE ()
+  };
+  struct MHD_DaemonOptionAndValue thread2poll[] = {
+    MHD_D_OPTION_POLL_SYSCALL (MHD_SPS_POLL),
+    MHD_D_OPTION_WM_WORKER_THREADS (1),
+    MHD_D_OPTION_TERMINATE ()
+  };
+  struct MHD_DaemonOptionAndValue thread1epoll[] = {
+    MHD_D_OPTION_POLL_SYSCALL (MHD_SPS_EPOLL),
+    MHD_D_OPTION_WM_WORKER_THREADS (1),
+    MHD_D_OPTION_TERMINATE ()
+  };
+  struct MHD_DaemonOptionAndValue thread2epoll[] = {
+    MHD_D_OPTION_POLL_SYSCALL (MHD_SPS_EPOLL),
+    MHD_D_OPTION_WM_WORKER_THREADS (1),
+    MHD_D_OPTION_TERMINATE ()
+  };
+  struct MHD_DaemonOptionAndValue thread1auto[] = {
+    MHD_D_OPTION_POLL_SYSCALL (MHD_SPS_AUTO),
+    MHD_D_OPTION_WM_WORKER_THREADS (1),
+    MHD_D_OPTION_TERMINATE ()
+  };
+  struct MHD_DaemonOptionAndValue external0auto[] = {
+    MHD_D_OPTION_POLL_SYSCALL (MHD_SPS_AUTO),
+    MHD_D_OPTION_WM_EXTERNAL_PERIODIC (),
+    MHD_D_OPTION_TERMINATE ()
+  };
+  struct ServerType
+  {
+    const char *label;
+    MHDT_ServerSetup server_setup;
+    void *server_setup_cls;
+    MHDT_ServerRunner server_runner;
+    void *server_runner_cls;
+  } configs[] = {
+    {
+      .label = "single threaded select",
+      .server_setup = &MHDT_server_setup_minimal,
+      .server_setup_cls = thread1select,
+      .server_runner = &MHDT_server_run_minimal,
+    },
+    {
+      .label = "multi-threaded select",
+      .server_setup = &MHDT_server_setup_minimal,
+      .server_setup_cls = thread2select,
+      .server_runner = &MHDT_server_run_minimal,
+    },
+#if HAVE_POLL
+    {
+      .label = "single threaded poll",
+      .server_setup = &MHDT_server_setup_minimal,
+      .server_setup_cls = thread1poll,
+      .server_runner = &MHDT_server_run_minimal,
+    },
+    {
+      .label = "multi-threaded poll",
+      .server_setup = &MHDT_server_setup_minimal,
+      .server_setup_cls = thread2poll,
+      .server_runner = &MHDT_server_run_minimal,
+    },
+#endif
+#if HAVE_EPOLL_CREATE1
+    {
+      .label = "single threaded epoll",
+      .server_setup = &MHDT_server_setup_minimal,
+      .server_setup_cls = thread1epoll,
+      .server_runner = &MHDT_server_run_minimal,
+    },
+    {
+      .label = "multi-threaded epoll",
+      .server_setup = &MHDT_server_setup_minimal,
+      .server_setup_cls = thread2epoll,
+      .server_runner = &MHDT_server_run_minimal,
+    },
+#endif
+    {
+      .label = "auto-selected mode, single threaded",
+      .server_setup = &MHDT_server_setup_minimal,
+      .server_setup_cls = thread1auto,
+      .server_runner = &MHDT_server_run_minimal,
+    },
+#if 1
+    /* FIXME: remove once MHD_daemon_process_blocking
+       has been implemented */
+    {
+      .label = "END"
+    },
+#endif
+    {
+      .label = "auto-selected external event loop mode, no threads",
+      .server_setup = &MHDT_server_setup_minimal,
+      .server_setup_cls = external0auto,
+      .server_runner = &MHDT_server_run_blocking,
+    },
+    {
+      .label = "END"
+    }
+  };
   struct MHDT_Phase phases[] = {
     {
       .label = "simple get",
@@ -74,15 +186,31 @@ main (int argc, char *argv[])
       .label = NULL,
     },
   };
+  unsigned int i;
+
   (void) argc; /* Unused. Silence compiler warning. */
   (void) argv; /* Unused. Silence compiler warning. */
 
-  // threading modi
-  // socket polling functions (select, poll, epoll, internal, external edge, external level)
-  //
-  return MHDT_test (&MHDT_server_setup_minimal,
-                    NULL,
-                    &MHDT_server_run_minimal,
-                    NULL,
-                    phases);
+  for (i = 0; NULL != configs[i].server_setup; i++)
+  {
+    int ret;
+
+    fprintf (stderr,
+             "Running tests with server setup `%s'\n",
+             configs[i].label);
+    ret = MHDT_test (configs[i].server_setup,
+                     configs[i].server_setup_cls,
+                     configs[i].server_runner,
+                     configs[i].server_runner_cls,
+                     phases);
+    if (0 != ret)
+    {
+      fprintf (stderr,
+               "Test failed with server of type `%s' (%u)\n",
+               configs[i].label,
+               i);
+      return ret;
+    }
+  }
+  return 0;
 }