diff --git a/Makefile b/Makefile
index 50cc9f3c..589a498a 100644
--- a/Makefile
+++ b/Makefile
@@ -121,15 +121,27 @@ else
 endif
 
 ifeq ($(detected_OS),Windows)
+  define to_win_path
+    $(subst /,\,$(1))
+  endef
   define remove_dir
     if exist $(1) ( $(RM) $(1) )
   endef
+  define remove_files
+    $(foreach file,$(call to_win_path,$(1)), IF EXIST $(file) ( $(RMFILE) $(file) ) & )
+  endef
 else
   define remove_dir
     $(RM) $(1)
   endef
+  define remove_files
+    $(RMFILE) $(1)
+  endef
 endif
 
+# Recursive wildcard: https://stackoverflow.com/a/18258352
+rwildcard=$(foreach d,$(wildcard $(1:=/*)),$(call rwildcard,$d,$2) $(filter $(subst *,%,$2),$d))
+
 $(info MSBUILD_PARAM: $(MSBUILD_PARAM))
 $(info nuget path: $(shell $(WHICH) nuget))
 $(info )
@@ -155,16 +167,35 @@ JAVA_CLEAN_TARGETS := \
 	clean_KP2AKdbLibrary \
 	clean_PluginQR
 
-OUTPUT_JavaFileStorageTest-AS = src/java/JavaFileStorage/app/build/outputs/aar/JavaFileStorage-debug.aar src/java/android-filechooser-AS/app/build/outputs/aar/android-filechooser-release.aar
-OUTPUT_KP2ASoftkeyboard_AS =src/java/KP2ASoftkeyboard_AS/app/build/outputs/aar/app-debug.aar
-OUTPUT_Keepass2AndroidPluginSDK2 = src/java/Keepass2AndroidPluginSDK2/app/build/outputs/aar/app-release.aar
-OUTPUT_KP2AKdbLibrary = src/java/KP2AKdbLibrary/app/build/outputs/aar/app-debug.aar
-OUTPUT_PluginQR = src/java/Keepass2AndroidPluginSDK2/app/build/outputs/aar/Keepass2AndroidPluginSDK2-release.aar src/java/PluginQR/app/build/outputs/apk/debug/app-debug.apk
+INPUT_JavaFileStorageTest-AS = $(call rwildcard,src/java/android-filechooser-AS/app/src,*) $(call rwildcard,src/java/JavaFileStorage/app/src,*) $(call rwildcard,src/java/JavaFileStorageTest-AS/app/src,*.java)
+OUTPUT_JavaFileStorageTest-AS = src/java/android-filechooser-AS/app/build/outputs/aar/android-filechooser-debug.aar \
+	src/java/android-filechooser-AS/app/build/outputs/aar/android-filechooser-release.aar \
+	src/java/JavaFileStorage/app/build/outputs/aar/JavaFileStorage-debug.aar \
+	src/java/JavaFileStorage/app/build/outputs/aar/JavaFileStorage-release.aar \
+	src/java/JavaFileStorageTest-AS/app/build/outputs/apk/debug/app-debug.apk \
+	src/java/JavaFileStorageTest-AS/app/build/outputs/apk/release/app-release-unsigned.apk
 
+INPUT_KP2ASoftkeyboard_AS = $(call rwildcard,src/java/KP2ASoftkeyboard_AS/app/src,*)
+OUTPUT_KP2ASoftkeyboard_AS = src/java/KP2ASoftkeyboard_AS/app/build/outputs/aar/app-debug.aar \
+	src/java/KP2ASoftkeyboard_AS/app/build/outputs/aar/app-release.aar
+
+INPUT_Keepass2AndroidPluginSDK2 = $(call rwildcard,src/java/Keepass2AndroidPluginSDK2/app/src,*)
+OUTPUT_Keepass2AndroidPluginSDK2 = src/java/Keepass2AndroidPluginSDK2/app/build/outputs/aar/app-debug.aar \
+	src/java/Keepass2AndroidPluginSDK2/app/build/outputs/aar/app-release.aar
+
+INPUT_KP2AKdbLibrary = $(call rwildcard,src/java/KP2AKdbLibrary/app/src,*)
+OUTPUT_KP2AKdbLibrary = src/java/KP2AKdbLibrary/app/build/outputs/aar/app-debug.aar \
+	src/java/KP2AKdbLibrary/app/build/outputs/aar/app-release.aar
+
+INPUT_PluginQR = $(call rwildcard,src/java/PluginQR/app/src,*)
+OUTPUT_PluginQR = src/java/Keepass2AndroidPluginSDK2/app/build/outputs/aar/Keepass2AndroidPluginSDK2-debug.aar \
+	src/java/Keepass2AndroidPluginSDK2/app/build/outputs/aar/Keepass2AndroidPluginSDK2-release.aar \
+	src/java/PluginQR/app/build/outputs/apk/debug/app-debug.apk \
+	src/java/PluginQR/app/build/outputs/apk/debug/app-release-unsigned.apk
 
 ##### Targets definition
 
-.PHONY: native $(NATIVE_COMPONENTS) clean_native $(NATIVE_CLEAN_TARGETS)  \
+.PHONY: native $(NATIVE_COMPONENTS) clean_native $(NATIVE_CLEAN_TARGETS) \
 	java $(JAVA_COMPONENTS) clean_java $(JAVA_CLEAN_TARGETS) \
 	nuget clean_nuget \
 	msbuild clean_msbuild \
@@ -177,7 +208,7 @@ all: apk
 native: $(NATIVE_COMPONENTS)
 
 argon2: $(OUTPUT_argon2)
-$(OUTPUT_argon2):
+$(OUTPUT_argon2): $(wildcard src/java/argon2/phc-winner-argon2/src/*)  $(wildcard src/java/argon2/phc-winner-argon2/src/blake2/*)
 	cd src/java/argon2 && $(ANDROID_NDK_ROOT)/ndk-build
 
 ##### Java Dependencies
@@ -190,15 +221,20 @@ Keepass2AndroidPluginSDK2: $(OUTPUT_Keepass2AndroidPluginSDK2)
 KP2AKdbLibrary: $(OUTPUT_KP2AKdbLibrary)
 PluginQR: $(OUTPUT_PluginQR)
 
-$(OUTPUT_JavaFileStorageTest-AS):
+$(OUTPUT_JavaFileStorageTest-AS): $(INPUT_JavaFileStorageTest-AS)
+	$(call remove_files,$(OUTPUT_JavaFileStorageTest-AS))
 	cd src/java/JavaFileStorageTest-AS && $(GRADLEW) assemble
-$(OUTPUT_KP2ASoftkeyboard_AS):
+$(OUTPUT_KP2ASoftkeyboard_AS): $(INPUT_KP2ASoftkeyboard_AS)
+	$(call remove_files,$(OUTPUT_KP2ASoftkeyboard_AS))
 	cd src/java/KP2ASoftkeyboard_AS && $(GRADLEW) assemble
-$(OUTPUT_Keepass2AndroidPluginSDK2):
+$(OUTPUT_Keepass2AndroidPluginSDK2): $(INPUT_Keepass2AndroidPluginSDK2)
+	$(call remove_files,$(OUTPUT_Keepass2AndroidPluginSDK2))
 	cd src/java/Keepass2AndroidPluginSDK2 && $(GRADLEW) assemble
-$(OUTPUT_KP2AKdbLibrary):
+$(OUTPUT_KP2AKdbLibrary): $(INPUT_KP2AKdbLibrary)
+	$(call remove_files,$(OUTPUT_KP2AKdbLibrary))
 	cd src/java/KP2AKdbLibrary && $(GRADLEW) assemble
-$(OUTPUT_PluginQR):
+$(OUTPUT_PluginQR): $(INPUT_PluginQR)
+	$(call remove_files,$(OUTPUT_PluginQR))
 	cd src/java/PluginQR && $(GRADLEW) assemble