diff --git a/demos/calc.cpp b/demos/calc.cpp
index 588f28b..03cf53c 100644
--- a/demos/calc.cpp
+++ b/demos/calc.cpp
@@ -7,9 +7,6 @@
 #include <fmt/xchar.h>
 #include <deque>
 
-#define FSM_DEBUG 1
-#include "fsm.hpp"
-
 constexpr const int WINDOW_WIDTH=300;
 constexpr const int WINDOW_HEIGHT=400;
 
diff --git a/fsm.hpp b/fsm.hpp
deleted file mode 100644
index 8729dd8..0000000
--- a/fsm.hpp
+++ /dev/null
@@ -1,28 +0,0 @@
-#pragma once
-
-#include <fmt/core.h>
-
-#ifndef FSM_DEBUG
-#define FSM_STATE(C, S, E, ...) case C::S: S(E, ##__VA_ARGS__); break
-#else
-#define FSM_STATE(C, S, E, ...) case C::S: fmt::println(">> " #C " " #S " event={}, state={}", int(E), int($state)); S(E, ##__VA_ARGS__); fmt::println("<< " #C " state={}", int($state)); break
-#endif
-
-template<typename S, typename E>
-class DeadSimpleFSM {
-protected:
-  // BUG: don't put this in your class because state() won't work
- S $state = S::START;
-
-public:
-  template<typename... Types>
-  void event(E event, Types... args);
-
-  void state(S next_state) {
-    $state = next_state;
-  }
-
-  bool in_state(S state) {
-    return $state == state;
-  }
-};