diff --git a/main/shared.h b/main/shared.h
index 7fee108..24dbdd2 100644
--- a/main/shared.h
+++ b/main/shared.h
@@ -25,6 +25,15 @@ static const char* APP_TAG="CINEKID_LEDS";
     printf("\n");\
 } while(0)
 
+static inline
+int min(int a, int b) { return a < b ? a : b; }
+static inline
+int max(int a, int b) { return a > b ? a : b; }
+static inline
+int clamp(int x, int mi, int ma) {
+    return max(mi, min(ma, x));
+}
+
 #define GLOBAL(__a) (uint8_t)(__a|0xE0)
 
 #endif // !_shared_h