diff --git a/scripts/gitea-release.sh b/scripts/gitea-release.sh
index 0daf893..70e7880 100755
--- a/scripts/gitea-release.sh
+++ b/scripts/gitea-release.sh
@@ -114,7 +114,7 @@ done
 files="$files dist/SHA256SUMS"
 
 # The release (created, or found when publishing again).
-release=$(call 404 "$api/releases/tags/$tag")
+release=$(call 404 "$api/releases/tags/$(printf '%s' "$tag" | sed 's/+/%2B/g')")
 id=$(printf '%s\n' "$release" | jq -r '.id // empty')
 if [ -z "$id" ]; then
 	body=$(jq -n --arg tag "$tag" --arg notes "$notes" --argjson pre "$prerelease" \
@@ -127,7 +127,8 @@ for f in $files; do
 	name=${f#dist/}
 	old=$(printf '%s\n' "$release" | jq -r --arg n "$name" '.assets[]? | select(.name == $n) | .id')
 	[ -z "$old" ] || call "" -X DELETE "$api/releases/$id/assets/$old" >/dev/null
-	call "" -X POST -F "attachment=@$f" "$api/releases/$id/assets?name=$name" >/dev/null
+	# A + (build metadata, 0.1.0-rc.1+git4-8fa62f9) would be a space in a query.
+	call "" -X POST -F "attachment=@$f" "$api/releases/$id/assets?name=$(printf '%s' "$name" | sed 's/+/%2B/g')" >/dev/null
 	echo "gitea-release: attached $name"
 done