Index: Mk/Scripts/create-manifest.sh
===================================================================
--- Mk/Scripts/create-manifest.sh
+++ Mk/Scripts/create-manifest.sh
@@ -104,6 +104,7 @@
 		output=${dp_METADIR}/+${prepost:+${prepost}_}${stage}
 		for input in ${files}; do
 			[ -f "${input}" ] && cat ${input} >> ${output}
+			[ -f "${input}.lua" ] && cp ${input}.lua ${dp_METADIR}
 		done
 	done
 done
Index: Mk/Scripts/depends-list.sh
===================================================================
--- Mk/Scripts/depends-list.sh
+++ Mk/Scripts/depends-list.sh
@@ -37,7 +37,7 @@
 done
 shift $((OPTIND-1))
 
-validate_env PORTSDIR dp_PKGNAME
+validate_env PORTSDIR dp_OVERLAYS dp_PKGNAME
 if [ ${recursive} -eq 1 -o ${requires_wrkdir} -eq 1 ]; then
 	validate_env dp_MAKE
 	# Cache command executions to avoid looking them up again in every
@@ -65,16 +65,25 @@
 
 		case "${2}" in
 		/*) d=${2} ;;
-		*) d=${PORTSDIR}/${2} ;;
+		*) for overlay in ${dp_OVERLAYS} ${PORTSDIR}; do
+			d=${overlay}/${2}
+			f=
+			case "${d}" in
+			*@*/*) ;; # Ignore @ in the path which would not be a flavor
+			*@*)
+				f=${d##*@}
+				d=${d%@*}
+				;;
+			esac
+			if [ -f ${d}/Makefile ]; then
+				if [ -n $f ]; then
+					export FLAVOR=$f
+				fi
+				break
+			fi
+		done
 		esac
 
-		case "${d}" in
-		*@*/*) ;; # Ignore @ in the path which would not be a flavor
-		*@*)
-			export FLAVOR=${d##*@}
-			d=${d%@*}
-			;;
-		esac
 		if [ ${flavors} -eq 1 -a -n "${FLAVOR:-}" ]; then
 			port_display="${d}@${FLAVOR}"
 		else
Index: Mk/Scripts/do-depends.sh
===================================================================
--- Mk/Scripts/do-depends.sh
+++ Mk/Scripts/do-depends.sh
@@ -11,7 +11,7 @@
 	dp_DEPENDS_CLEAN dp_DEPENDS_ARGS dp_USE_PACKAGE_DEPENDS \
 	dp_USE_PACKAGE_DEPENDS_ONLY dp_PKG_ADD dp_PKG_INFO dp_WRKDIR \
 	dp_PKGNAME dp_STRICT_DEPENDS dp_LOCALBASE dp_LIB_DIRS dp_SH \
-	dp_SCRIPTSDIR PORTSDIR dp_MAKE dp_MAKEFLAGS
+	dp_SCRIPTSDIR PORTSDIR dp_MAKE dp_MAKEFLAGS dp_OVERLAYS
 
 [ -n "${DEBUG_MK_SCRIPTS}" -o -n "${DEBUG_MK_SCRIPTS_DO_DEPENDS}" ] && set -x
 
@@ -125,7 +125,15 @@
 
 	case "${origin}" in
 	/*) ;;
-	*) origin="${PORTSDIR}/${origin}" ;;
+	*)
+		for overlay in ${dp_OVERLAYS} ${PORTSDIR}; do
+			orig="${overlay}/${origin}"
+			if [ -f "${orig}/Makefile" ]; then
+				break
+			fi
+		done
+		origin="${orig}"
+		;;
 	esac
 	case "${origin}" in
 	*@*/*) ;; # Ignore @ in the path which would not be a flavor
Index: Mk/bsd.port.mk
===================================================================
--- Mk/bsd.port.mk
+++ Mk/bsd.port.mk
@@ -1029,6 +1029,7 @@
 NOTPHONY?=
 FLAVORS?=
 FLAVOR?=
+OVERLAYS?=
 # Disallow forced FLAVOR as make argument since we cannot change it to the
 # proper default.
 .if empty(FLAVOR) && !empty(.MAKEOVERRIDES:MFLAVOR)
@@ -1450,8 +1451,18 @@
 .endif
 .endfor
 .for f in ${USES}
-.include "${USESDIR}/${f:C/\:.*//}.mk"
+.undef _usefound
+.for udir in ${OVERLAYS:C,$,/Mk/Uses,} ${USESDIR}
+_usefile=	${udir}/${f:C/\:.*//}.mk
+.if exists(${_usefile}) && !defined(_usefound)
+_usefound=
+.include "${_usefile}"
+.endif
 .endfor
+.if !defined(_usefound)
+ERROR+=	"Unkonwn USES=${f:C/\:.*//}"
+.endif
+.endfor
 
 .if !empty(FLAVORS)
 .  if ${FLAVORS:Mall}
@@ -1962,8 +1973,18 @@
 .endif
 .endfor
 .for f in ${_USES_POST}
-.include "${USESDIR}/${f:C/\:.*//}.mk"
+.undef _usefound
+.for udir in ${OVERLAYS:C,$,/Mk/Uses,} ${USESDIR}
+_usefile=	${udir}/${f:C/\:.*//}.mk
+.if exists(${_usefile}) && !defined(_usefound)
+_usefound=
+.include "${_usefile}"
+.endif
 .endfor
+.if !defined(_usefound)
+ERROR+=	"Unkonwn USES=${f:C/\:.*//}"
+.endif
+.endfor
 
 .if defined(PORTNAME)
 .include "${PORTSDIR}/Mk/bsd.sanity.mk"
@@ -3212,8 +3233,7 @@
 .endif
 
 # Build
-# XXX: ${MAKE_ARGS:N${DESTDIRNAME}=*} would be easier but it is not valid with the old fmake
-DO_MAKE_BUILD?=	${SETENV} ${MAKE_ENV} ${MAKE_CMD} ${MAKE_FLAGS} ${MAKEFILE} ${_MAKE_JOBS} ${MAKE_ARGS:C,^${DESTDIRNAME}=.*,,g}
+DO_MAKE_BUILD?=	${SETENV} ${MAKE_ENV} ${MAKE_CMD} ${MAKE_FLAGS} ${MAKEFILE} ${_MAKE_JOBS} ${MAKE_ARGS:N${DESTDIRNAME}=*}
 .if !target(do-build)
 do-build:
 	@(cd ${BUILD_WRKSRC}; if ! ${DO_MAKE_BUILD} ${ALL_TARGET}; then \
@@ -3333,7 +3353,7 @@
 # Test
 
 .if !target(do-test) && defined(TEST_TARGET)
-DO_MAKE_TEST?=	${SETENV} ${TEST_ENV} ${MAKE_CMD} ${MAKE_FLAGS} ${MAKEFILE} ${TEST_ARGS:C,^${DESTDIRNAME}=.*,,g}
+DO_MAKE_TEST?=	${SETENV} ${TEST_ENV} ${MAKE_CMD} ${MAKE_FLAGS} ${MAKEFILE} ${TEST_ARGS:N${DESTDIRNAME}=*}
 do-test:
 	@(cd ${TEST_WRKSRC}; if ! ${DO_MAKE_TEST} ${TEST_TARGET}; then \
 		if [ -n "${TEST_FAIL_MESSAGE}" ] ; then \
@@ -3965,6 +3985,7 @@
 		dp_SH="${SH}" \
 		dp_SCRIPTSDIR="${SCRIPTSDIR}" \
 		PORTSDIR="${PORTSDIR}" \
+		dp_OVERLAYS="${OVERLAYS}" \
 		dp_MAKE="${MAKE}" \
 		dp_MAKEFLAGS='${.MAKEFLAGS}' \
 		${SH} ${SCRIPTSDIR}/do-depends.sh
@@ -4019,6 +4040,7 @@
 			dp_PKGNAME="${PKGNAME}" \
 			dp_PKG_INFO="${PKG_INFO}" \
 			dp_SCRIPTSDIR="${SCRIPTSDIR}" \
+			dp_OVERLAYS="${OVERLAYS}" \
 			${SH} ${SCRIPTSDIR}/depends-list.sh \
 			${DEPENDS_SHOW_FLAVOR:D-f}
 
Index: Mk/bsd.sanity.mk
===================================================================
--- Mk/bsd.sanity.mk
+++ Mk/bsd.sanity.mk
@@ -58,7 +58,7 @@
 
 # Warnings only when DEVELOPER=yes
 
-.if exists(${.CURDIR}/../../Mk/bsd.port.mk)
+.if exists(${.CURDIR}/../../Mk/bsd.port.mk) || ${OVERLAYS:tA:M${.CURDIR:H:H}} == ${.CURDIR:H:H}
 .if ${.CURDIR:H:T} != ${PKGCATEGORY}
 DEV_ERROR+=	"The first entry in CATEGORIES should be the directory where the port lives"
 .endif