diff --git a/README.rst b/README.rst
index 3c571d5..761f2cb 100644
--- a/README.rst
+++ b/README.rst
@@ -1,7 +1,12 @@
 Instructions
 ============
 
-First, ``cargo install debcargo``. Then for each new package:
+To get set up, run::
+
+  apt update && apt build-dep cargo && apt install cargo dh-cargo
+  cargo install debcargo # eventually will be replaced by "apt install debcargo"
+
+Then for each new package:
 
 **To package a new crate, or to update an existing crate:**
 
diff --git a/build.sh b/build.sh
new file mode 100755
index 0000000..1035daf
--- /dev/null
+++ b/build.sh
@@ -0,0 +1,72 @@
+#!/bin/sh
+set -e
+
+abort() { local x=$1; shift; for i in "$@"; do echo >&2 "$0: abort: $i"; done; exit "$x"; }
+
+if [ "$(basename "$PWD")" != "build" ]; then
+	abort 1 "This script is only meant to be run from the build/ directory."
+fi
+
+if [ -n "$DEBCARGO" ]; then
+	true
+elif which debcargo >/dev/null; then
+	DEBCARGO=$(which debcargo)
+elif [ -f "$HOME/.cargo/bin/debcargo" ]; then
+	DEBCARGO="$HOME/.cargo/bin/debcargo"
+else
+	abort 1 "debcargo not found, run \`cargo install debcargo\` or set DEBCARGO to point to it"
+fi
+
+CRATE="$1"
+VER="$2"
+DISTRIBUTION="${DISTRIBUTION:-unstable}"
+
+PKGNAME=$($DEBCARGO deb-src-name "$CRATE" $VER || abort 1 "couldn't find crate $CRATE")
+DEBVER=$(dpkg-parsechangelog -l $PKGNAME/debian/changelog -SVersion)
+DEBSRC=$(dpkg-parsechangelog -l $PKGNAME/debian/changelog -SSource)
+DEBDIST=$(dpkg-parsechangelog -l $PKGNAME/debian/changelog -SDistribution)
+DEB_HOST_ARCH=$(dpkg-architecture -q DEB_HOST_ARCH)
+if [ -z "$CHROOT" ] && schroot -i -c "debcargo-unstable-${DEB_HOST_ARCH}-sbuild" >/dev/null 2>&1; then
+	CHROOT="debcargo-unstable-${DEB_HOST_ARCH}-sbuild"
+fi
+
+shouldbuild() {
+	local dst="$1"
+	local src="$2"
+	test ! -e "$dst" -o "$src" -nt "$dst"
+}
+
+if shouldbuild ${DEBSRC}_${DEBVER}.dsc "$PKGNAME/debian/changelog" ]; then
+	( cd "$PKGNAME" && dpkg-buildpackage -d -S --no-sign )
+	# sign if not UNRELEASED
+	if echo "$DEBDIST" | grep -qv UNRELEASED-FIXME-AUTOGENERATED-DEBCARGO; then
+		debsign ${DEBSRC}_${DEBVER}_source.changes
+	fi
+fi
+
+check_build_deps() {
+	mkdir -p dpkg-dummy
+	if shouldbuild dpkg-dummy/status /var/cache/apt/pkgcache.bin; then
+		# pretend dpkg status file that marks all packages as installed
+		# this is because dpkg-checkbuilddeps only works on installed pkgs
+		apt-cache dumpavail | \
+		sed -e 's/Package: .*/\0\nStatus: install ok installed/g' > dpkg-dummy/status
+	fi
+	cd "$PKGNAME" && dpkg-checkbuilddeps --admindir=../dpkg-dummy
+}
+
+if ! check_build_deps; then
+	abort 1 "Missing build-dependencies, but maybe try '{apt,cargo} update'"
+fi
+
+if [ "$SOURCEONLY" = 1 ]; then
+	exit
+fi
+
+sbuild --no-source --arch-any --arch-all ${CHROOT:+-c $CHROOT }${DISTRIBUTION:+-d $DISTRIBUTION }${DEBSRC}_${DEBVER}.dsc
+changestool ${DEBSRC}_${DEBVER}_${DEB_HOST_ARCH}.changes adddsc ${DEBSRC}_${DEBVER}.dsc
+
+# sign if not UNRELEASED
+if echo "$DEBDIST" | grep -qv UNRELEASED-FIXME-AUTOGENERATED-DEBCARGO; then
+	debsign ${DEBSIGN_KEYID:+-k $DEBSIGN_KEYID }--no-re-sign ${DEBSRC}_${DEBVER}_${DEB_HOST_ARCH}.changes
+fi
diff --git a/dev/filter-builddeps-ok.sh b/dev/filter-builddeps-ok.sh
new file mode 100755
index 0000000..07c7a4f
--- /dev/null
+++ b/dev/filter-builddeps-ok.sh
@@ -0,0 +1,24 @@
+#!/bin/bash
+# Filter list of crates by whether all their build-deps are in Debian
+# Use like, e.g. `dev/list-unreleased.sh | dev/filter-builddeps-ok.sh`
+set -e
+
+shouldbuild() {
+	local dst="$1"
+	local src="$2"
+	test ! -e "$dst" -o "$src" -nt "$dst"
+}
+
+echo >&2 "redirecting all other output e.g. from debcargo to stderr"
+while read crate ver; do
+	pkgname="${crate//_/-}${ver:+-$ver}"
+	if shouldbuild "build/$pkgname/debian/changelog" "src/$pkgname/debian/changelog"; then
+		./update.sh "$crate" $ver >&2 # TODO: no-overlay-write-back
+	fi
+	if ( cd build && SOURCEONLY=1 ./build.sh "$crate" $ver >&2 ); then
+		ok=1
+	else
+		ok=0
+	fi
+	echo "$crate $ver $ok"
+done
diff --git a/dev/list-unreleased.sh b/dev/list-unreleased.sh
index f06a8d3..c158249 100755
--- a/dev/list-unreleased.sh
+++ b/dev/list-unreleased.sh
@@ -8,5 +8,5 @@
 cut '-d ' -f1 | \
 while read crate; do
 	pkg="${crate//_/-}"
-	head -n1 src/$pkg/debian/changelog
+	sed -nre "s/.*Package (.*) .* from crates.io.*/\1/gp" src/$pkg/debian/changelog | head -n1
 done
diff --git a/release.sh b/release.sh
index 52f9d32..f1eacc2 100755
--- a/release.sh
+++ b/release.sh
@@ -11,6 +11,9 @@
 
 git diff --quiet -- "$PKGDIR_REL" || \
 abort 1 "Please git-add your changes to $PKGDIR_REL before running"
+
+type dch >/dev/null || \
+abort 1 "Install devscripts, we need to run dch."
 
 RELBRANCH="pending-$PKGNAME"
 git fetch origin --prune
@@ -59,61 +62,15 @@
 	abort 1 "Release attempt resulted in git diffs to $PKGDIR_REL, probably the package needs updating (./update.sh $*)"
 fi
 
-check_build_deps() {
-	local success=true
-	sed -ne '/Build-Depends/,/^[^ ]/p' "build/$PKGNAME/debian/control" | \
-	grep -Eo 'librust-.*+.*-dev' | \
-	{ while read pkg; do
-		if [ $(apt-cache showpkg "$pkg" | grep ^Package: | wc -l) = 0 ]; then
-			echo >&2 "Build-Dependency not yet in debian: $pkg (don't forget to '{apt,cargo} update')"
-			success=false
-		fi
-	done; $success; }
-}
-
-if ! check_build_deps; then
+if ! ( cd build && SOURCEONLY=1 ./build.sh "$CRATE" $VER ); then
 	revert_git_changes
 	abort 1 "Release attempt detected build-dependencies not in Debian (see messages above), release those first."
 fi
 
 git commit -m "Release package $PKGNAME"
 
-( cd "$BUILDDIR" && dpkg-buildpackage -d -S --no-sign )
-
-cat >"$BUILDDIR/../sbuild-and-sign.sh" <<'eof'
-#!/bin/sh
-set -e
-
-if [ -n "$DEBCARGO" ]; then
-	true
-elif which debcargo >/dev/null; then
-	DEBCARGO=$(which debcargo)
-elif [ -f "$HOME/.cargo/bin/debcargo" ]; then
-	DEBCARGO="$HOME/.cargo/bin/debcargo"
-else
-	abort 1 "debcargo not found, run \`cargo install debcargo\` or set DEBCARGO to point to it"
-fi
-
-CRATE="$1"
-VER="$2"
-DISTRIBUTION="${DISTRIBUTION:-unstable}"
-
-PKGNAME=$($DEBCARGO deb-src-name "$CRATE" $VER || abort 1 "couldn't find crate $CRATE")
-DEBVER=$(dpkg-parsechangelog -l $PKGNAME/debian/changelog -SVersion)
-DEBSRC=$(dpkg-parsechangelog -l $PKGNAME/debian/changelog -SSource)
-DEB_HOST_ARCH=$(dpkg-architecture -q DEB_HOST_ARCH)
-if [ -z "$CHROOT" ] && schroot -i -c "debcargo-unstable-${DEB_HOST_ARCH}-sbuild" >/dev/null 2>&1; then
-	CHROOT="debcargo-unstable-${DEB_HOST_ARCH}-sbuild"
-fi
-
-sbuild --no-source --arch-any --arch-all ${CHROOT:+-c $CHROOT }${DISTRIBUTION:+-d $DISTRIBUTION }${DEBSRC}_${DEBVER}.dsc
-changestool ${DEBSRC}_${DEBVER}_${DEB_HOST_ARCH}.changes adddsc ${DEBSRC}_${DEBVER}.dsc
-debsign ${DEBSIGN_KEYID:+-k $DEBSIGN_KEYID }--no-re-sign ${DEBSRC}_${DEBVER}_${DEB_HOST_ARCH}.changes
-eof
-chmod +x "$BUILDDIR/../sbuild-and-sign.sh"
-
-DEBVER=$(dpkg-parsechangelog -l build/$PKGNAME/debian/changelog -SVersion)
-DEBSRC=$(dpkg-parsechangelog -l build/$PKGNAME/debian/changelog -SSource)
+DEBVER=$(dpkg-parsechangelog -l $BUILDDIR/debian/changelog -SVersion)
+DEBSRC=$(dpkg-parsechangelog -l $BUILDDIR/debian/changelog -SSource)
 DEB_HOST_ARCH=$(dpkg-architecture -q DEB_HOST_ARCH)
 cat >&2 <<eof
 Release of $CRATE ready as a source package in ${BUILDDIR#$PWD/}. You need to
@@ -125,17 +82,13 @@
 If the source package is already in Debian and this version does not introduce
 new binaries, then you can just go ahead and directly dput the source package.
 
-  cd build
-  debsign ${DEBSRC}_${DEBVER}_source.changes
-  dput ${DEBSRC}_${DEBVER}_source.changes
+  cd build && dput ${DEBSRC}_${DEBVER}_source.changes
 
 If this is a NEW source package or introduces NEW binary packages not already
 in the Debian archive, you will need to build a binary package out of it. The
 recommended way is to run something like:
 
-  cd build
-  ./sbuild-and-sign.sh $CRATE $VER
-  dput ${DEBSRC}_${DEBVER}_${DEB_HOST_ARCH}.changes
+  cd build && ./build.sh $CRATE $VER && dput ${DEBSRC}_${DEBVER}_${DEB_HOST_ARCH}.changes
 
 This assumes you followed the "DD instructions" in README.rst, for setting up
 a build environment for release.
diff --git a/update.sh b/update.sh
index a197fbe..68975c9 100755
--- a/update.sh
+++ b/update.sh
@@ -43,7 +43,7 @@
 run_debcargo
 
 if ! git diff --quiet -- "$PKGDIR_REL"; then
-	read -p "Update wrote some changes to $PKGDIR_REL, press enter to git diff..." x
+	read -p "Update wrote some changes to $PKGDIR_REL, press enter to git diff..." x || true
 	git diff -- "$PKGDIR_REL"
 	echo >&2 "-- end of git diff --"
 fi
@@ -79,10 +79,20 @@
 any auto-generated hint files. If so, you should make the equivalent changes to
 the non-hint files, and git-add these too.
 
-When satisfied with the output, you can commit and push all your changes. Then,
-ask a Debian Developer to run \`./release.sh $*\` to finalise your changes in
-the changelog and build a release-ready .dsc in build/. Assuming it runs
-successfully, they may \`dput\` the results afterwards. If you're not a Debian
-Developer and are unable to upload, please don't run that script because it
-will add inaccurate commits to git stating that the package has been uploaded.
+You can test-build your package by running:
+
+  cd build && ./build.sh $CRATE $VER
+
+This assumes that you have set up sbuild; see "DD instructions" in README.rst
+for details. Try to fix any lintian errors, but note that some errors are due
+to lintian being out-of-date and/or are expected at this stage of the process
+(e.g. bad-distribution-in-changes-file). Ask on IRC when in doubt.
+
+When satisfied with the output (both of debcargo after running ./update.sh, and
+of lintian after running ./build.sh), you can commit and push all your changes.
+
+Then, ask a Debian Developer to run \`./release.sh $*\`. This finalises your
+changes in the changelog, and allows them to build and upload the package. If
+you're not a Debian Developer and are unable to upload, please don't run that
+script or else you will need to revert the changes that it makes to your git.
 eof
diff --git a/vars.sh.frag b/vars.sh.frag
index 10b2d78..4a39c5a 100644
--- a/vars.sh.frag
+++ b/vars.sh.frag
@@ -58,6 +58,8 @@
 PKGCFG="$PKGDIR/debian/debcargo.toml"
 
 mkdir -p "$(dirname $BUILDDIR)"
+cp "$PWD/build.sh" "$PWD/build/build.sh"
+chmod +x "$PWD/build/build.sh"
 
 if [ -z "$CRATE" ]; then
 	abort 2 "Usage: $0 <crate> [<version>]"