diff --git a/Mk/bsd.gecko.mk b/Mk/bsd.gecko.mk
index dd320f78067f..eaab374887e0 100644
--- a/Mk/bsd.gecko.mk
+++ b/Mk/bsd.gecko.mk
@@ -88,6 +88,8 @@ USES+=		cpe gmake iconv localbase perl5 pkgconfig \
 CPE_VENDOR?=mozilla
 USE_PERL5=	build
 USE_XORG=	x11 xcomposite xdamage xext xfixes xrender xt
+HAS_CONFIGURE=	yes
+CONFIGURE_OUTSOURCE=	yes
 
 .if ${MOZILLA} != "libxul"
 BUNDLE_LIBS=	yes
@@ -128,14 +130,10 @@ MOZILLA_SUFX?=	none
 MOZSRC?=	${WRKSRC}
 PLISTF?=	${WRKDIR}/plist_files
 
-MOZ_OBJDIR?=	${WRKSRC}/obj-${ARCH:C/amd64/x86_64/}-unknown-${OPSYS:tl}${OSREL}
-
 MOZ_PIS_DIR?=		lib/${MOZILLA}/init.d
 
 PORT_MOZCONFIG?=	${FILESDIR}/mozconfig.in
 MOZCONFIG?=		${WRKSRC}/.mozconfig
-# XXX Not ?= because fmake uses MAKEFILE internally
-MAKEFILE=		${WRKSRC}/client.mk
 MOZILLA_PLIST_DIRS?=	bin lib share/pixmaps share/applications
 PKGINSTALL?=	${WRKDIR}/pkg-install
 PKGDEINSTALL?=	${WRKDIR}/pkg-deinstall
@@ -145,14 +143,11 @@ PKGDEINSTALL_INC?=	${.CURDIR}/../../www/firefox/files/pkg-deinstall.in
 MOZ_PKGCONFIG_FILES?=	${MOZILLA}-gtkmozembed ${MOZILLA}-js \
 			${MOZILLA}-xpcom ${MOZILLA}-plugin
 
-MAKE_ENV+=		MACH=1 # XXX bug 1412398
-ALL_TARGET?=	build
-
 MOZ_EXPORT+=	${CONFIGURE_ENV} \
 				RUSTFLAGS="${RUSTFLAGS}" \
 				PERL="${PERL}"
 MOZ_OPTIONS+=	--prefix="${PREFIX}"
-MOZ_MK_OPTIONS+=MOZ_OBJDIR="${MOZ_OBJDIR}"
+MOZ_MK_OPTIONS+=MOZ_OBJDIR="${BUILD_WRKSRC}"
 
 LDFLAGS+=		-Wl,--as-needed