diff --git a/makefile b/makefile
index c62b645..da6e14d 100644
--- a/makefile
+++ b/makefile
@@ -4,25 +4,25 @@ LDFLAGS = -ljack -lm -lncurses -lpthread
 
 all: jack-looper test_engine test_tui test_gui test_cli test_stress
 
-jack-looper: main.o engine.o tui.o gui.o cli.o transport.o lib/microui.o
+jack-looper: main.o engine.o tui.o gui.o cli.o transport.o lib/microui.o wav_io.o
 	$(CC) $(CFLAGS) -o $@ $^ $(LDFLAGS)
 
-test_engine: test_engine.o engine.o transport.o
+test_engine: test_engine.o engine.o transport.o wav_io.o
 	$(CC) $(CFLAGS) -o $@ $^ $(LDFLAGS)
 
-test_tui: test_tui.o engine.o transport.o
+test_tui: test_tui.o engine.o transport.o wav_io.o
 	$(CC) $(CFLAGS) -o $@ $^ $(LDFLAGS)
 
 test_gui: test_gui.o gui.o engine.o transport.o lib/microui.o
 	$(CC) $(CFLAGS) -o $@ $^ $(LDFLAGS)
 
-test_cli: test_cli.o engine.o cli.o transport.o
+test_cli: test_cli.o engine.o cli.o transport.o wav_io.o
 	$(CC) $(CFLAGS) -o $@ $^ $(LDFLAGS)
 
-test_double_process: test_double_process.o engine.o transport.o
+test_double_process: test_double_process.o engine.o transport.o wav_io.o
 	$(CC) $(CFLAGS) -o $@ $^ $(LDFLAGS)
 
-test_stress: test_stress.o engine.o transport.o
+test_stress: test_stress.o engine.o transport.o wav_io.o
 	$(CC) $(CFLAGS) -o $@ $^ $(LDFLAGS)
 
 test_stress.o: test_stress.c engine.h tui.h transport.h
@@ -31,7 +31,10 @@ test_stress.o: test_stress.c engine.h tui.h transport.h
 main.o: main.c engine.h tui.h transport.h
 	$(CC) $(CFLAGS) -c -o $@ $<
 
-engine.o: engine.c engine.h transport.h
+engine.o: engine.c engine.h transport.h wav_io.h
+	$(CC) $(CFLAGS) -c -o $@ $<
+
+wav_io.o: wav_io.c wav_io.h
 	$(CC) $(CFLAGS) -c -o $@ $<
 
 tui.o: tui.c tui.h engine.h transport.h
@@ -67,7 +70,7 @@ cli.o: cli.c cli.h engine.h transport.h
 .PHONY: all clean test
 
 clean:
-	rm -f *.o lib/microui.o jack-looper test_engine test_tui test_gui test_cli test_double_process test_stress
+	rm -f *.o lib/microui.o wav_io.o jack-looper test_engine test_tui test_gui test_cli test_double_process test_stress
 
 test: test_engine test_tui test_cli test_double_process test_stress
 	./test_engine