diff --git a/release/Makefile b/release/Makefile
--- a/release/Makefile
+++ b/release/Makefile
@@ -89,31 +89,62 @@
 .endfor
 .endif
 
-.if !defined(NOPKGBASE) || empty(NOPKGBASE)
-PKGBASE_REPO_DIR= pkgbase-repo-dir
-PKG_NAME_PREFIX!= ${IMAKE} -f Makefile.inc1 -C ${WORLDDIR} -V PKG_NAME_PREFIX
-WSTAGEDIR!=	${IMAKE} -f Makefile.inc1 -C ${WORLDDIR} -V WSTAGEDIR
+# Determine what we want to put on the media.  NOPKG turns off ports packages
+# (e.g., wifi firmware), while NOPKGBASE turns off base packages and uses
+# dist sets instead.  If both are disabled, we avoid installing pkg at all.
 
-PKG_ABI_FILE=	${WSTAGEDIR}/usr/bin/uname
-PKG_ABI=	$$(${PKG_CMD} -o ABI_FILE=${PKG_ABI_FILE} config ABI)
+_USE_PKG=yes
+_USE_PKGBASE=yes
+_USE_PORTS=yes
+
+.if defined(NOPKGBASE) && !empty(NOPKGBASE)
+_USE_PKGBASE=no
+.else
+. if ${.MAKE.OS} != "FreeBSD"
+.  error Building pkgbase release media is only supported on FreeBSD.
+. endif
 .endif
 
-.if ${.MAKE.OS} == "FreeBSD"
+.if defined(NOPKG) && !empty(NOPKG)
+_USE_PORTS=no
+.else
+. if ${.MAKE.OS} != "FreeBSD"
+.  error Building release media with third-party packages is only supported on FreeBSD.
+. endif
+.endif
+
+.if ${_USE_PKGBASE} == "no" && ${_USE_PKG} == "no"
+_USE_PKG=no
+.endif
+
+.if ${_USE_PKG} != "no"
 # For installing packages into the release media.
-PKG_ENV+=	INSTALL_AS_USER=yes
-PKG_ENV+=	ASSUME_ALWAYS_YES=yes
+WSTAGEDIR!=	${IMAKE} -f Makefile.inc1 -C ${WORLDDIR} -V WSTAGEDIR
+PKG_ABI_FILE=	${WSTAGEDIR}/usr/bin/uname
+# We can't use != here because worldstage might not exist yet.
+PKG_ABI=	$$(${PKG_CMD} -o ABI_FILE=${PKG_ABI_FILE} config ABI)
+
+PKG_ARGS+=	-o INSTALL_AS_USER=yes
+PKG_ARGS+=	-o ASSUME_ALWAYS_YES=yes
 PKG_ARGS+=	-o METALOG=METALOG
 PKG_ARGS+=	-o ABI=${PKG_ABI}
 PKG_ARGS+=	-r ${.TARGET}
-PKG_REPO_ARGS=	-o REPOS_DIR=${.CURDIR}/pkg_repos
-PKGBASE_REPO_ARGS=-o REPOS_DIR=${.OBJDIR}/pkgbase-repo-dir
+
 # Pass -f to make sure pkg writes to the METALOG even if the package
 # is already installed from a previous build
-PKG_INSTALL=	env ${PKG_ENV} ${PKG_CMD} ${PKG_ARGS} ${PKG_REPO_ARGS} install -f
-PKG_CLEAN=	env ${PKG_ENV} ${PKG_CMD} ${PKG_ARGS} ${PKG_REPO_ARGS} clean -a
+PKG_REPO_ARGS=	-o REPOS_DIR=${.CURDIR}/pkg_repos
+PKG_INSTALL=	${PKG_CMD} ${PKG_ARGS} ${PKG_REPO_ARGS} install -f
+PKG_CLEAN=	${PKG_CMD} ${PKG_ARGS} ${PKG_REPO_ARGS} clean -a
+.endif
+
+.if ${_USE_PKGBASE} != "no"
+PKG_NAME_PREFIX!= ${IMAKE} -f Makefile.inc1 -C ${WORLDDIR} -V PKG_NAME_PREFIX
+
 # This installs from the pkgbase repo we created during build.
-PKGBASE_INSTALL=env ${PKG_ENV} ${PKG_CMD} ${PKG_ARGS} ${PKGBASE_REPO_ARGS} install -f
-PKGBASE_CLEAN=	env ${PKG_ENV} ${PKG_CMD} ${PKG_ARGS} ${PKGBASE_REPO_ARGS} clean -a
+PKGBASE_REPO_DIR= pkgbase-repo-dir
+PKGBASE_REPO_ARGS=-o REPOS_DIR=${.OBJDIR}/${PKGBASE_REPO_DIR}
+PKGBASE_INSTALL=${PKG_CMD} ${PKG_ARGS} ${PKGBASE_REPO_ARGS} install -f
+PKGBASE_CLEAN=	${PKG_CMD} ${PKG_ARGS} ${PKGBASE_REPO_ARGS} clean -a
 .endif
 
 .if !defined(VOLUME_LABEL) || empty(VOLUME_LABEL)
@@ -121,6 +152,9 @@
 .endif
 
 .if !exists(${PORTSDIR})
+. if ${_USE_PKGBASE} != "no"
+.  error PORTSDIR (${PORTSDIR}) must exist to build pkgbase media.
+. endif
 NOPORTS= true
 .endif
 
@@ -151,7 +185,7 @@
 IMAGES+=	memstick.img
 IMAGES+=	mini-memstick.img
 .endif
-.if !defined(NOPKGBASE) || empty(NOPKGBASE)
+.if ${_USE_PKGBASE} != "no"
 RELEASE_TARGETS+= pkgbase-repo.tar
 .endif
 
@@ -177,6 +211,7 @@
 #
 # Legacy distribution tarballs
 #
+.if !defined(NODISTSETS) || empty(NODISTSETS)
 base.txz: # Also (if enabled) tests, compat libs, and -dbg variants for all.
 	mkdir -p ${DISTDIR}
 	( cd ${WORLDDIR} && ${IMAKE} distributeworld DISTDIR=${.OBJDIR}/${DISTDIR} )
@@ -222,17 +257,12 @@
 	sh ${.CURDIR}/scripts/make-manifest.sh $$(ls *.txz | grep -v container) > MANIFEST
 	touch ${.TARGET}
 
-.if !defined(NODISTSETS) || empty(NODISTSETS)
 disc1: packagesystem
 bootonly: packagesystem
 dvd: packagesystem
 .endif
-.if !defined(NOPKGBASE) || empty(NOPKGBASE)
-disc1: pkgbase-repo-dir
-bootonly: pkgbase-repo-dir
-dvd: pkgbase-repo-dir
-.endif
 
+.if ${_USE_PKGBASE} != "no"
 pkgbase-repo:
 	mkdir -p pkgbase-repo
 	( ${IMAKE} -C ${WORLDDIR} packages REPODIR=${.OBJDIR}/pkgbase-repo \
@@ -247,10 +277,15 @@
 	    ${.OBJDIR}/pkgbase-repo/${PKG_ABI}/latest \
 	    > pkgbase-repo-dir/FreeBSD-base.conf
 
+disc1: pkgbase-repo-dir
+bootonly: pkgbase-repo-dir
+dvd: pkgbase-repo-dir
+.endif
+
 # Install a system suitable for an installer from the release package repo.
 # This is usually invoked via submake by the various media targets, and
 # should not be added as a dependency of other targets.
-.if make(install-system)
+.if ${_USE_PKGBASE} != "no" && make(install-system)
 
 . if !defined(INSTALL_SYSTEM_ROOT) || empty(INSTALL_SYSTEM_ROOT)
 .  error INSTALL_SYSTEM_ROOT must be defined
@@ -293,7 +328,7 @@
 .endif	# make(install-system)
 
 disc1:
-.if !defined(NOPKGBASE) || empty(NOPKGBASE)
+.if ${_USE_PKGBASE} != "no"
 # Install system
 	${MAKE} -C ${.CURDIR} \
 	    INSTALL_SYSTEM_ROOT=${.OBJDIR}/${.TARGET} \
@@ -321,25 +356,30 @@
 	    MK_RESCUE=no MK_DICT=no \
 	    MK_KERNEL_SYMBOLS=no MK_TESTS=no MK_DEBUG_FILES=no)
 .endif	# if pkgbase
+
+# If we're building pkgbase media (i.e., NODISTSETS isn't defined),
+# copy MANIFEST (the distset checksums) to allow a network install.
 .if !defined(NODISTSETS) || empty(NODISTSETS)
 	# Copy MANIFEST to provide legacy dist checksums in both modes
 	mkdir -p ${.TARGET}/usr/freebsd-dist
 	echo "./usr/freebsd-dist type=dir uname=root gname=wheel mode=0755" >> ${.TARGET}/METALOG
 	cp MANIFEST ${.TARGET}/usr/freebsd-dist
 	echo "./usr/freebsd-dist/MANIFEST type=file uname=root gname=wheel mode=0644" >> ${.TARGET}/METALOG
-.if defined(NOPKGBASE) && !empty(NOPKGBASE)
-# Copy distfiles
+.if ${_USE_PKGBASE} == "no"
+# For non-pkgbase media, also copy the actual sets.
 	for dist in $$(ls *.txz | grep -v container | grep -vE -- '(${base ${_ALL_libcompats}:L:ts|})-dbg'); do \
 	    cp $${dist} ${.TARGET}/usr/freebsd-dist; \
 	    echo "./usr/freebsd-dist/$${dist} type=file uname=root gname=wheel mode=0644" >> ${.TARGET}/METALOG; \
 	done
 .endif
 .endif
-.if ${.MAKE.OS} == "FreeBSD" && (!defined(NOPKG) || empty(NOPKG))
+
+.if ${_USE_PORTS} != "no"
 # Install packages onto release media.
-	${PKG_INSTALL} pkg ${RELEASE_MEDIA_EXTRA_PACKAGES} || true
-	${PKG_CLEAN} || true
+	${PKG_INSTALL} pkg ${RELEASE_MEDIA_EXTRA_PACKAGES}
+	${PKG_CLEAN}
 .endif
+
 # Set up installation environment
 	ln -fs /tmp/bsdinstall_etc/resolv.conf ${.TARGET}/etc/resolv.conf
 	echo sendmail_enable=\"NONE\" > ${.TARGET}/etc/rc.conf
@@ -359,7 +399,7 @@
 
 bootonly:
 # Install system
-.if !defined(NOPKGBASE) || empty(NOPKGBASE)
+.if ${_USE_PKGBASE} != "no"
 	${MAKE} -C ${.CURDIR} \
 	    INSTALL_SYSTEM_ROOT=${.OBJDIR}/${.TARGET} \
 	    INSTALL_SYSTEM_MEDIATYPE="${.TARGET}" \
@@ -375,6 +415,7 @@
 	    MK_RESCUE=no MK_DICT=no \
 	    MK_KERNEL_SYMBOLS=no MK_TESTS=no MK_DEBUG_FILES=no)
 .endif	# if pkgbase
+
 .if !defined(NODISTSETS) || empty(NODISTSETS)
 # Copy manifest only (no distfiles) to get checksums
 	mkdir -p ${.TARGET}/usr/freebsd-dist
@@ -382,10 +423,12 @@
 	echo "./usr/freebsd-dist type=dir uname=root gname=wheel mode=0755" >> ${.TARGET}/METALOG
 	echo "./usr/freebsd-dist/MANIFEST type=file uname=root gname=wheel mode=0644" >> ${.TARGET}/METALOG
 .endif
-.if ${.MAKE.OS} == "FreeBSD" && (!defined(NOPKG) || empty(NOPKG))
-	${PKG_INSTALL} pkg ${RELEASE_MEDIA_EXTRA_PACKAGES} || true
-	${PKG_CLEAN} || true
+
+.if ${_USE_PORTS} != "no"
+	${PKG_INSTALL} pkg ${RELEASE_MEDIA_EXTRA_PACKAGES}
+	${PKG_CLEAN}
 .endif
+
 # Set up installation environment
 	ln -fs /tmp/bsdinstall_etc/resolv.conf ${.TARGET}/etc/resolv.conf
 	echo sendmail_enable=\"NONE\" > ${.TARGET}/etc/rc.conf
@@ -403,7 +446,7 @@
 	echo "./etc/rc.local type=file uname=root gname=wheel mode=0644" >> ${.TARGET}/METALOG
 
 dvd:
-.if !defined(NOPKGBASE) || empty(NOPKGBASE)
+.if ${_USE_PKGBASE} != "no"
 # Install system
 	${MAKE} -C ${.CURDIR} \
 	    INSTALL_SYSTEM_ROOT=${.OBJDIR}/${.TARGET} \
@@ -427,24 +470,26 @@
 		DESTDIR=${.OBJDIR}/${.TARGET} MK_RESCUE=no MK_KERNEL_SYMBOLS=no \
 		MK_TESTS=no MK_DEBUG_FILES=no)
 .endif	# if pkgbase
+
+# Copy distfiles
 .if !defined(NODISTSETS) || empty(NODISTSETS)
-	# Copy MANIFEST to provide legacy dist checksums in both modes
 	mkdir -p ${.TARGET}/usr/freebsd-dist
 	echo "./usr/freebsd-dist type=dir uname=root gname=wheel mode=0755" >> ${.TARGET}/METALOG
 	cp MANIFEST ${.TARGET}/usr/freebsd-dist
 	echo "./usr/freebsd-dist/MANIFEST type=file uname=root gname=wheel mode=0644" >> ${.TARGET}/METALOG
-# Copy distfiles
 	mkdir -p ${.TARGET}/usr/freebsd-dist
 	for dist in $$(ls *.txz | grep -v container); do \
 	    cp $${dist} ${.TARGET}/usr/freebsd-dist; \
 	    echo "./usr/freebsd-dist/$${dist} type=file uname=root gname=wheel mode=0644" >> ${.TARGET}/METALOG; \
 	done
 .endif
-.if ${.MAKE.OS} == "FreeBSD" && (!defined(NOPKG) || empty(NOPKG))
+
+.if ${_USE_PORTS} != "no"
 # Install packages onto release media.
-	${PKG_INSTALL} pkg ${RELEASE_MEDIA_EXTRA_PACKAGES} || true
-	${PKG_CLEAN} || true
+	${PKG_INSTALL} pkg ${RELEASE_MEDIA_EXTRA_PACKAGES}
+	${PKG_CLEAN}
 .endif
+
 # Set up installation environment
 	ln -fs /tmp/bsdinstall_etc/resolv.conf ${.TARGET}/etc/resolv.conf
 	echo sendmail_enable=\"NONE\" > ${.TARGET}/etc/rc.conf
@@ -489,7 +534,7 @@
 	cd bootonly-memstick && sh ${.CURDIR}/${TARGET}/make-memstick.sh ./METALOG ../${.TARGET}
 
 pkg-stage: dvd
-.if !defined(NOPKG) || empty(NOPKG)
+.if ${_USE_PORTS} != "no"
 	env PORTSDIR=${PORTSDIR} REPOS_DIR=${.CURDIR}/pkg_repos/ \
 		sh ${.CURDIR}/scripts/pkg-stage.sh -N
 	mkdir -p ${.OBJDIR}/dvd/packages/repos/