diff --git a/aos/events/ping.cc b/aos/events/ping.cc
index 5a79635..f829b41 100644
--- a/aos/events/ping.cc
+++ b/aos/events/ping.cc
@@ -6,11 +6,13 @@
 #include "gflags/gflags.h"
 #include "glog/logging.h"
 
+DEFINE_string(config, "aos/events/pingpong_config.json", "Path to the config.");
+
 int main(int argc, char **argv) {
   aos::InitGoogle(&argc, &argv);
 
   aos::FlatbufferDetachedBuffer<aos::Configuration> config =
-      aos::configuration::ReadConfig("aos/events/pingpong_config.json");
+      aos::configuration::ReadConfig(FLAGS_config);
 
   aos::ShmEventLoop event_loop(&config.message());
 
diff --git a/aos/events/ping_lib.cc b/aos/events/ping_lib.cc
index 4bbf580..9bc2446 100644
--- a/aos/events/ping_lib.cc
+++ b/aos/events/ping_lib.cc
@@ -1,13 +1,12 @@
 #include "aos/events/ping_lib.h"
 
-#include "aos/events/pong_generated.h"
 #include "aos/events/ping_generated.h"
+#include "aos/events/pong_generated.h"
 #include "aos/json_to_flatbuffer.h"
 #include "gflags/gflags.h"
 #include "glog/logging.h"
 
 DEFINE_int32(sleep_ms, 10, "Time to sleep between pings");
-DEFINE_bool(phased_loop, false, "If true, use a phased loop");
 
 namespace aos {
 
@@ -15,25 +14,16 @@
 
 Ping::Ping(EventLoop *event_loop)
     : event_loop_(event_loop),
-      sender_(event_loop_->MakeSender<examples::Ping>("/test")),
-      pong_fetcher_(event_loop_->MakeFetcher<examples::Pong>("/test")) {
-  if (FLAGS_phased_loop) {
-    phased_loop_handle_ = event_loop_->AddPhasedLoop(
-        [this](int) { SendPing(); }, chrono::milliseconds(FLAGS_sleep_ms));
-    phased_loop_handle_->set_name("ping");
-  } else {
-    timer_handle_ = event_loop_->AddTimer([this]() { SendPing(); });
-    timer_handle_->set_name("ping");
-  }
+      sender_(event_loop_->MakeSender<examples::Ping>("/test")) {
+  timer_handle_ = event_loop_->AddTimer([this]() { SendPing(); });
+  timer_handle_->set_name("ping");
 
   event_loop_->MakeWatcher(
       "/test", [this](const examples::Pong &pong) { HandlePong(pong); });
 
   event_loop_->OnRun([this]() {
-    if (!FLAGS_phased_loop) {
-      timer_handle_->Setup(event_loop_->monotonic_now(),
-                           chrono::milliseconds(FLAGS_sleep_ms));
-    }
+    timer_handle_->Setup(event_loop_->monotonic_now(),
+                         chrono::milliseconds(FLAGS_sleep_ms));
   });
 
   event_loop_->SetRuntimeRealtimePriority(5);
@@ -41,17 +31,16 @@
 
 void Ping::SendPing() {
   ++count_;
-  aos::Sender<examples::Ping>::Builder msg = sender_.MakeBuilder();
-  examples::Ping::Builder builder = msg.MakeBuilder<examples::Ping>();
-  builder.add_value(count_);
-  builder.add_send_time(
+  aos::Sender<examples::Ping>::Builder builder = sender_.MakeBuilder();
+  examples::Ping::Builder ping_builder = builder.MakeBuilder<examples::Ping>();
+  ping_builder.add_value(count_);
+  ping_builder.add_send_time(
       event_loop_->monotonic_now().time_since_epoch().count());
-  CHECK(msg.Send(builder.Finish()));
+  CHECK(builder.Send(ping_builder.Finish()));
   VLOG(2) << "Sending ping";
 }
 
 void Ping::HandlePong(const examples::Pong &pong) {
-  pong_fetcher_.Fetch();
   const aos::monotonic_clock::time_point monotonic_send_time(
       chrono::nanoseconds(pong.initial_send_time()));
   const aos::monotonic_clock::time_point monotonic_now =
@@ -60,11 +49,19 @@
   const chrono::nanoseconds round_trip_time =
       monotonic_now - monotonic_send_time;
 
+  if (last_pong_value_ + 1 != pong.value()) {
+    LOG(WARNING) << "Pong message lost";
+  }
+
   if (pong.value() == count_) {
     VLOG(1) << "Elapsed time " << round_trip_time.count() << " ns "
             << FlatbufferToJson(&pong);
   } else {
-    VLOG(1) << "Missmatched pong message";
+    LOG(WARNING) << "Missmatched pong message, got " << FlatbufferToJson(&pong)
+                 << " expected " << count_;
   }
+
+  last_pong_value_ = pong.value();
 }
+
 }  // namespace aos
diff --git a/aos/events/ping_lib.h b/aos/events/ping_lib.h
index 6be75ed..e14c3f2 100644
--- a/aos/events/ping_lib.h
+++ b/aos/events/ping_lib.h
@@ -25,10 +25,10 @@
   aos::Sender<examples::Ping> sender_;
   // Timer handle which sends the Ping message.
   aos::TimerHandler *timer_handle_;
-  aos::PhasedLoopHandler *phased_loop_handle_;
-  aos::Fetcher<examples::Pong> pong_fetcher_;
   // Number of pings sent.
   int count_ = 0;
+  // Last pong value received so we can detect missed pongs.
+  int last_pong_value_ = 0;
 };
 
 }  // namespace aos
diff --git a/aos/events/pong.cc b/aos/events/pong.cc
index 339d4d7..581d04f 100644
--- a/aos/events/pong.cc
+++ b/aos/events/pong.cc
@@ -6,13 +6,15 @@
 #include "aos/init.h"
 #include "glog/logging.h"
 
+DEFINE_string(config, "aos/events/pingpong_config.json", "Path to the config.");
+
 int main(int argc, char **argv) {
   FLAGS_logtostderr = true;
   google::InitGoogleLogging(argv[0]);
   ::gflags::ParseCommandLineFlags(&argc, &argv, true);
 
   aos::FlatbufferDetachedBuffer<aos::Configuration> config =
-      aos::configuration::ReadConfig("aos/events/pingpong_config.json");
+      aos::configuration::ReadConfig(FLAGS_config);
 
   ::aos::ShmEventLoop event_loop(&config.message());
 
diff --git a/aos/events/pong_lib.cc b/aos/events/pong_lib.cc
index 5ff38b9..9d7731d 100644
--- a/aos/events/pong_lib.cc
+++ b/aos/events/pong_lib.cc
@@ -1,8 +1,8 @@
 #include "aos/events/pong_lib.h"
 
 #include "aos/events/event_loop.h"
-#include "aos/events/pong_generated.h"
 #include "aos/events/ping_generated.h"
+#include "aos/events/pong_generated.h"
 #include "glog/logging.h"
 
 namespace aos {
@@ -11,11 +11,12 @@
     : event_loop_(event_loop),
       sender_(event_loop_->MakeSender<examples::Pong>("/test")) {
   event_loop_->MakeWatcher("/test", [this](const examples::Ping &ping) {
-    aos::Sender<examples::Pong>::Builder msg = sender_.MakeBuilder();
-    examples::Pong::Builder builder = msg.MakeBuilder<examples::Pong>();
-    builder.add_value(ping.value());
-    builder.add_initial_send_time(ping.send_time());
-    CHECK(msg.Send(builder.Finish()));
+    aos::Sender<examples::Pong>::Builder builder = sender_.MakeBuilder();
+    examples::Pong::Builder pong_builder =
+        builder.MakeBuilder<examples::Pong>();
+    pong_builder.add_value(ping.value());
+    pong_builder.add_initial_send_time(ping.send_time());
+    CHECK(builder.Send(pong_builder.Finish()));
   });
 
   event_loop_->SetRuntimeRealtimePriority(5);