diff --git a/aos/realtime.h b/aos/realtime.h
index 6e0a472..52db4a8 100644
--- a/aos/realtime.h
+++ b/aos/realtime.h
@@ -4,6 +4,8 @@
 #include <sched.h>
 #include <string_view>
 
+#include "glog/logging.h"
+
 namespace aos {
 
 // Locks everything into memory and sets the limits.  This plus InitNRT are
@@ -34,6 +36,55 @@
 
 void ExpandStackSize();
 
+// CHECKs that we are (or are not) running on the RT scheduler.  Useful for
+// enforcing that operations which are or are not bounded shouldn't be run. This
+// works both in simulation and when running against the real target.
+void CheckRealtime();
+void CheckNotRealtime();
+
+// Marks that we are or are not running on the realtime scheduler.  Returns the
+// previous state.
+//
+// Note: this shouldn't be used directly.  The event loop primitives should be
+// used instead.
+bool MarkRealtime(bool realtime);
+
+// Class which restores the current RT state when destructed.
+class ScopedRealtimeRestorer {
+ public:
+  ScopedRealtimeRestorer();
+  ~ScopedRealtimeRestorer() { MarkRealtime(prior_); }
+
+ private:
+  const bool prior_;
+};
+
+// Class which marks us as on the RT scheduler until it goes out of scope.
+// Note: this shouldn't be needed for most applications.
+class ScopedRealtime {
+ public:
+  ScopedRealtime() : prior_(MarkRealtime(true)) {}
+  ~ScopedRealtime() {
+    CHECK(MarkRealtime(prior_)) << ": Priority was modified";
+  }
+
+ private:
+  const bool prior_;
+};
+
+// Class which marks us as not on the RT scheduler until it goes out of scope.
+// Note: this shouldn't be needed for most applications.
+class ScopedNotRealtime {
+ public:
+  ScopedNotRealtime() : prior_(MarkRealtime(false)) {}
+  ~ScopedNotRealtime() {
+    CHECK(!MarkRealtime(prior_)) << ": Priority was modified";
+  }
+
+ private:
+  const bool prior_;
+};
+
 }  // namespace aos
 
 #endif  // AOS_REALTIME_H_