diff --git a/build_tools/make_linux_packages.sh b/build_tools/make_linux_packages.sh
new file mode 100755
index 000000000..a2ebc86cd
--- /dev/null
+++ b/build_tools/make_linux_packages.sh
@@ -0,0 +1,83 @@
+#!/bin/sh
+
+# This script takes a source tarball (from build_tools/make_tarball.sh) and a vendor tarball (from
+# build_tools/make_vendor_tarball.sh, generated if not present), and produces:
+# * Appropriately-named symlinks to look like a Debian package
+# * Debian .changes and .dsc files with plain names ($version-1) and supported Ubuntu prefixes
+#   ($version-1~somedistro)
+# * An RPM spec file
+# By default, input and output files go in ~/fish_built, but this can be controlled with the
+# FISH_ARTEFACT_PATH environment variable.
+
+{
+
+set -e
+
+version=$1
+[ -n "$version" ] || { echo "Version number required as argument" >&2; exit 1; }
+
+
+[ -n "$DEB_SIGN_KEYID$DEB_SIGN_KEYFILE" ] ||
+    echo "Warning: neither DEB_SIGN_KEYID or DEB_SIGN_KEYFILE environment variables are set; you
+will need a signing key for the author of the most recent debian/changelog entry." >&2
+
+workpath=${FISH_ARTEFACT_PATH:-~/fish_built}
+source_tarball="$workpath"/fish-"$version".tar.xz
+vendor_tarball="$workpath"/fish-"$version"-vendor.tar.xz
+
+[ -e "$source_tarball" ] || { echo "Missing source tarball, expected at $source_tarball" >&2; exit 1; }
+cd "$workpath"
+
+# Unpack the sources
+tar xf "$source_tarball"
+sourcepath="$workpath"/fish-"$version"
+
+# Generate the vendor tarball if it is not already present
+[ -e "$vendor_tarball" ] || (cd "$sourcepath"; build_tools/make_vendor_tarball.sh;)
+
+# This step requires network access, so do it early in case it fails
+# sh has no real array support
+ubuntu_versions=$(uv run --script "$sourcepath"/build_tools/supported_ubuntu_versions.py)
+
+# Write the specfile
+[ -e "$workpath"/fish.spec ] && { echo "Cowardly refusing to overwite an existing fish.spec" >&2;
+exit 1; }
+rpmversion=$(echo "$version" |sed -e 's/-/+/' -e 's/-/./g')
+sed -e "s/@version@/$version/g" -e "s/@rpmversion@/$rpmversion/g" \
+    < "$sourcepath"/fish.spec.in > "$workpath"/fish.spec
+
+# Make the symlinks for Debian
+ln -s "$source_tarball" "$workpath"/fish_"$version".orig.tar.xz
+ln -s "$vendor_tarball" "$workpath"/fish_"$version".orig-cargo-vendor.tar.xz
+
+# Set up the Debian source tree
+cd "$sourcepath"
+mkdir cargo-vendor
+tar -C cargo-vendor -x -f "$vendor_tarball"
+cp -r contrib/debian debian
+
+# The vendor tarball contains a new .cargo/config.toml, which has the
+# vendoring overrides appended to it. dpkg-source will add this as a
+# patch using the flags in debian/
+cp cargo-vendor/.cargo/config.toml .cargo/config.toml
+
+# Update the Debian changelog
+# The release scripts do this for release builds - skip if it has already been done
+if head -n1 debian/changelog | grep --invert-match --quiet --fixed-strings "$version"; then
+    debchange --newversion "$version-1" --distribution unstable "Snapshot build"
+fi
+
+# Builds the "plain" Debian package
+# debuild runs lintian, which takes ten minutes to run over the vendor directories
+# just use dpkg-buildpackage directly
+dpkg-buildpackage --build=source -d
+
+# Build the Ubuntu packages
+# deb-reversion does not work on source packages, so do the whole thing ourselves
+for series in $ubuntu_versions; do
+    sed -i -e "1 s/$version-1)/$version-1~$series)/" -e "1 s/unstable/$series/" debian/changelog
+    dpkg-buildpackage --build=source -d
+    sed -i -e "1 s/$version-1~$series)/$version-1)/" -e "1 s/$series/unstable/" debian/changelog
+done
+
+}