add super simple makefile for building a single file

makefile

@@ -0,0 +1,21 @@
+CC      := gcc
+CFLAGS  := -Wall -Wextra -std=c11
+LDLIBS  := -lSDL2 -lSDL2_image
+
+TARGET  := waveform
+
+SRC     := waveform.c
+
+# -------------------------------------------------
+# Default target – just type `make` to build
+all: $(TARGET)
+
+# How to build the executable
+$(TARGET): $(SRC)
+	$(CC) $(CFLAGS) $^ $(LDLIBS) -o $@
+
+# Convenience: `make clean` to remove the binary
+clean:
+	rm -f $(TARGET)
+
+.PHONY: all clean