diff --git a/.gitignore b/.gitignore
index 48d7b4a..072831b 100644
--- a/.gitignore
+++ b/.gitignore
@@ -3,7 +3,7 @@ bin/
 *.bin
 *.o
 *.code-workspace
-tests/cmocka/
+tests/build/
 tests/bin/
 tests/obj/
 out/
diff --git a/Dockerfile b/Dockerfile
index 02daa80..d6cc2ed 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -11,9 +11,6 @@ RUN apt-get -y update && \
     unzip && \
     git config --global --add safe.directory "*"
 WORKDIR /app
-COPY tests/cmocka-*.tar.xz /app/tests/
-COPY tests/Makefile /app/tests/Makefile
-RUN make -C tests cmocka
 COPY . /app
 EXPOSE 2345
 ENTRYPOINT []
diff --git a/tests/Makefile b/tests/Makefile
index 71f898f..e21dd1e 100644
--- a/tests/Makefile
+++ b/tests/Makefile
@@ -5,7 +5,7 @@ SGDK?=/sgdk
 BIN_DIR=bin
 OBJ_DIR=obj
 CMOCKA_TAR=third_party/cmocka-1.1.7.tar.xz
-CMOCKA_DIR=cmocka
+CMOCKA_DIR=build/deps/cmocka
 
 ifeq ($(DEBUG),1)
 	GDB=gdbserver :2345
@@ -233,7 +233,7 @@ system: $(SYSTEM_TESTS_TARGET)
 	$(GDB) ./$(SYSTEM_TESTS_TARGET)
 .PHONY: system
 
-$(OBJ_DIR)/%.o: %.c
+$(OBJ_DIR)/%.o: %.c | $(CMOCKA_DIR)
 	@mkdir -p $(dir $@)
 	$(CC) $(CFLAGS) -MMD -MT "$@ $(basename $@).d" -c $< -o $@
 
@@ -258,5 +258,5 @@ clean-target:
 .PHONY: clean-target
 
 clean: clean-target
-	rm -rf $(CMOCKA_DIR)
+	rm -rf build/
 .PHONY: clean