diff --git a/obfuscator.hpp b/obfuscator.hpp
index e004671..67bbfb0 100644
--- a/obfuscator.hpp
+++ b/obfuscator.hpp
@@ -4,6 +4,9 @@
 #include <type_traits>
 #include <utility>
 
+#define OBFS_FINITE_STATE_MACHINE
+#define STATE(Name) struct Name {};
+#define EVENT(Name) struct Name {};
 #define COMPILE_TIME_RANDOM
 #define MAKE_RAND_VAL(MOD) RAND_VAL<__LINE__, MOD>
 #define COMPILE_TIME_SEQUENCE
@@ -11,6 +14,70 @@
 #define MAKE_STRING(Var, String, ...) constexpr auto Var = obfs::make_string<__VA_ARGS__>(String);
 
 
+namespace obfs {
+    template <typename Event, typename State>
+    struct Next {
+        using event = Event;
+        using state = State;
+    };
+
+    struct FalseType {};
+
+    template <typename IfFalse, typename T, typename... Ts>
+    struct First {
+        using type = std::conditional_t<
+            std::is_same_v<T, FalseType>,
+            typename First<IfFalse, Ts...>::type,
+            T>;
+    };
+
+    template <typename IfFalse, typename T>
+    struct First<IfFalse, T> {
+        using type = std::conditional_t<
+            std::is_same_v<T, FalseType>,
+            IfFalse,
+            T>;
+    };
+
+    template <typename State, typename... Nexts>
+    struct Stage {
+
+        template <typename Cond, typename Event>
+        using act = std::conditional_t<
+            std::is_same_v<typename Cond::event, Event>,
+            typename Cond::state,
+            FalseType>;
+
+        template <typename Event>
+        using next = typename First<State, act<Nexts, Event>...>::type;
+    };
+
+    template <typename... Specs>
+    struct StateMachine {
+
+    };
+
+
+    STATE(Final);
+
+    EVENT(none);
+    EVENT(Trigger);
+
+    STATE(state1); STATE(state2); STATE(state3); STATE(state4); STATE(state5);
+    EVENT(event1); EVENT(event2); EVENT(event3); EVENT(event4); EVENT(event5);
+
+    using machine = StateMachine<
+        Stage<state1, Next<event5, state2>,
+                      Next<event1, state3>>,
+        Stage<state2, Next<event2, state4>>,
+        Stage<state3, Next<none, state3>>,
+        Stage<state4, Next<event4, state1>,
+                      Next<event3, state5>>,
+        Stage<state5, Next<Trigger, Final>>>;
+
+}
+
+
 namespace obfs {
     constexpr char TIME[] = __TIME__;
     constexpr int digit(char c) {
diff --git a/obfuscator/obfs/fsm.hpp b/obfuscator/obfs/fsm.hpp
new file mode 100644
index 0000000..2990a02
--- /dev/null
+++ b/obfuscator/obfs/fsm.hpp
@@ -0,0 +1,71 @@
+#ifndef OBFS_FINITE_STATE_MACHINE
+#define OBFS_FINITE_STATE_MACHINE
+
+#include <type_traits>
+
+namespace obfs {
+    template <typename Event, typename State>
+    struct Next {
+        using event = Event;
+        using state = State;
+    };
+
+    struct FalseType {};
+
+    template <typename IfFalse, typename T, typename... Ts>
+    struct First {
+        using type = std::conditional_t<
+            std::is_same_v<T, FalseType>,
+            typename First<IfFalse, Ts...>::type,
+            T>;
+    };
+
+    template <typename IfFalse, typename T>
+    struct First<IfFalse, T> {
+        using type = std::conditional_t<
+            std::is_same_v<T, FalseType>,
+            IfFalse,
+            T>;
+    };
+
+    template <typename State, typename... Nexts>
+    struct Stage {
+
+        template <typename Cond, typename Event>
+        using act = std::conditional_t<
+            std::is_same_v<typename Cond::event, Event>,
+            typename Cond::state,
+            FalseType>;
+
+        template <typename Event>
+        using next = typename First<State, act<Nexts, Event>...>::type;
+    };
+
+    template <typename... Specs>
+    struct StateMachine {
+        
+    };
+
+#define STATE(Name) struct Name {};
+#define EVENT(Name) struct Name {};
+
+    STATE(Final);
+
+    EVENT(none);
+    EVENT(Trigger);
+
+    STATE(state1); STATE(state2); STATE(state3); STATE(state4); STATE(state5);
+    EVENT(event1); EVENT(event2); EVENT(event3); EVENT(event4); EVENT(event5);
+
+    using machine = StateMachine<
+        Stage<state1, Next<event5, state2>,
+                      Next<event1, state3>>,
+        Stage<state2, Next<event2, state4>>,
+        Stage<state3, Next<none, state3>>,
+        Stage<state4, Next<event4, state1>,
+                      Next<event3, state5>>,
+        Stage<state5, Next<Trigger, Final>>>;
+
+}
+
+#endif
\ No newline at end of file
diff --git a/obfuscator/obfuscator.hpp b/obfuscator/obfuscator.hpp
index a51090e..2c74c15 100644
--- a/obfuscator/obfuscator.hpp
+++ b/obfuscator/obfuscator.hpp
@@ -1,6 +1,7 @@
 #ifndef OBFUSCATOR
 #define OBFUSCATOR
 
+#include "obfs/fsm.hpp"
 #include "obfs/random.hpp"
 #include "obfs/sequence.hpp"
 #include "obfs/string.hpp"