--- a/im/config/mozconfigs/linux/mozconfig
+++ b/im/config/mozconfigs/linux/mozconfig
@@ -1,15 +1,15 @@
 export MOZILLA_OFFICIAL=1
 mk_add_options MOZILLA_OFFICIAL=1
 
 export CFLAGS="-gstabs+ -Wno-sign-compare"
 export CXXFLAGS="-gstabs+"
 
-mk_add_options MOZ_MAKE_FLAGS="-j4"
+mk_add_options MOZ_MAKE_FLAGS="-j4 CC='ccache gcc' CXX='ccache g++'"
 mk_add_options MOZ_OBJDIR=@TOPSRCDIR@/../obj-instantbird
 
 ac_add_options --enable-application=instantbird
 ac_add_options --enable-update-channel=nightly
 ac_add_options --enable-update-packaging
 ac_add_options --enable-optimize
 ac_add_options --disable-debug
 ac_add_options --disable-tests