diff --git a/Makefile b/Makefile
index c3380e7..94ba90d 100644
--- a/Makefile
+++ b/Makefile
@@ -49,6 +49,7 @@
 
 ifeq ($(findstring y,$(UNATTENDED)),y)
 CONFIRM=-y
+FORCE=--force-yes
 endif
 
 .PHONY: help bootstrap wipe wipe-release build build-release rebuild rebuild-release
@@ -128,11 +129,11 @@
 install-dep:
 ifeq ($(OS_ID),ubuntu)
 ifeq ($(OS_VERSION_ID),14.04)
-	@sudo -E apt-get $(CONFIRM) install software-properties-common
-	@sudo -E add-apt-repository $(CONFIRM) ppa:openjdk-r/ppa
+	@sudo -E apt-get $(CONFIRM) $(FORCE) install software-properties-common
+	@sudo -E add-apt-repository ppa:openjdk-r/ppa $(CONFIRM)
 	@sudo -E apt-get update
 endif
-	@sudo -E apt-get $(CONFIRM) install $(DEB_DEPENDS)
+	@sudo -E apt-get $(CONFIRM) $(FORCE) install $(DEB_DEPENDS)
 else ifneq ("$(wildcard /etc/redhat-release)","")
 	@sudo yum groupinstall $(CONFIRM) $(RPM_DEPENDS_GROUPS)
 	@sudo yum install $(CONFIRM) $(RPM_DEPENDS)