diff --git a/.forgejo/upload-rpms.sh b/.forgejo/upload-rpms.sh
new file mode 100755
index 00000000..30bbf34b
--- /dev/null
+++ b/.forgejo/upload-rpms.sh
@@ -0,0 +1,47 @@
+#!/usr/bin/env bash
+# Uploads the RPMs a build downloaded (its dnf cache, kept by
+# Containerfile.in's cache mounts) to this forge's RPM registry, one group
+# per upstream repository: fedora, updates, terra, copr-ublue-os-packages...
+# Each group is a dnf repository at
+# https://forge.quinefoundation.com/api/packages/quine-global-labs/rpm/<group>.
+#
+# Usage: upload-rpms.sh CACHE_DIR   (a libdnf5 cache: one directory per
+# repository, <repo id>-<hash>/packages/*.rpm)
+#
+# Needs REGISTRY_USER and REGISTRY_TOKEN (package write access). Packages
+# the registry already has are skipped (409). Best effort: a failed upload
+# is a warning, not a failure.
+set -euo pipefail
+
+cache=$1
+api=${RPM_API:-https://forge.quinefoundation.com/api/packages/quine-global-labs/rpm}
+
+# The token goes to curl in a file, not on its command line.
+netrc=$(mktemp)
+trap 'rm -f "$netrc"' EXIT
+chmod 600 "$netrc"
+printf 'machine %s login %s password %s\n' \
+  "$(sed -E 's|^https?://([^/]+).*|\1|' <<<"$api")" "$REGISTRY_USER" "$REGISTRY_TOKEN" >"$netrc"
+
+upload() { # group rpm
+  local code
+  code=$(curl -sS -o /dev/null -w '%{http_code}' --retry 3 --netrc-file "$netrc" \
+    --upload-file "$2" "$api/$1/upload") || code=000
+  case $code in
+    201) echo "new $1 ${2##*/}" ;;
+    409) echo "had $1 ${2##*/}" ;;
+    *) echo "::warning::$code uploading ${2##*/} to $1" ;;
+  esac
+}
+export -f upload
+export api netrc
+
+for dir in "$cache"/*/; do
+  id=$(basename "$dir")
+  id=${id%-*} # the hash libdnf5 appends
+  [[ $id == @* ]] && continue # @commandline: local files, not a repository
+  # copr:copr.fedorainfracloud.org:ublue-os:packages -> copr-ublue-os-packages
+  group=$(sed -E 's/^copr:[^:]+:/copr-/; s/:/-/g' <<<"$id")
+  find "$dir" -name '*.rpm' -printf "$group\0%p\0"
+done | xargs -0 -n 2 -P 4 bash -c 'upload "$@"' _ |
+  tee /dev/stderr | awk '{n[$1]++} END {for (k in n) printf "%s: %d\n", k, n[k]}'