diff --git a/src/check b/src/check
index d66a2ef..4019dc4 100755
--- a/src/check
+++ b/src/check
@@ -9,3 +9,5 @@ filter='[
   {"digest": $version}
 ] | tostring'
 jq -r --null-input --arg version "$(crane digest "$REPOSITORY:$TAG")" "$filter"
+
+rm "$INPUT_FILE"
diff --git a/src/in b/src/in
index 857cc33..ffd60d3 100755
--- a/src/in
+++ b/src/in
@@ -6,12 +6,23 @@ set -eu
 . ./common
 
 oci_dir="$(mktemp -d)"
-crane pull --format=oci "$REPOSITORY:@$(jq -r .version.digest "$INPUT_FILE")" "$oci_dir"
+digest="$(jq -r .version.digest < "$INPUT_FILE")"
+crane pull --format=oci "$REPOSITORY:@$digest" "$oci_dir"
 cd "$oci_dir"
+
+# write outputs
 tar cf "$1/image.tar" ./*
+echo "$REPOSITORY" > "$1/repository"
+echo "$digest" > "$1/digest"
+
 cd - 1>&2 2>/dev/null
 
+# output
 filter='{
   "version": .version
 } | tostring'
 jq -r "$filter" < "$INPUT_FILE"
+
+# cleanup
+rm -r "$oci_dir"
+rm "$INPUT_FILE"
diff --git a/src/out b/src/out
index 95be4c2..081b965 100755
--- a/src/out
+++ b/src/out
@@ -5,14 +5,28 @@ set -eu
 [ -e /opt/resource/common ] && cd /opt/resource
 . ./common
 
-IMAGE_REFS_FILE="$(mktemp -t)"
+image_refs_file="$(mktemp -t)"
 oci_dir="$(mktemp -d)"
 cd "$oci_dir"
 tar xf "$1/$(jq -r .params.image < "$INPUT_FILE")"
 cd - 1>&2 2>/dev/null
-crane push "$oci_dir" "$REPOSITORY:$TAG" --image-refs="$IMAGE_REFS_FILE"
+
+crane push "$oci_dir" "$REPOSITORY:$TAG" --image-refs="$image_refs_file"
+additional_tags="$(jq .params.additional_tags < "$INPUT_FILE")"
+if [ -n "$additional_tags" ]; then
+    if ! [ -e "$additional_tags" ]; then
+        fail "additional_tags specified, but doesn't exist"
+    fi
+    tr ' \n\t' '\n\n\n' | grep -v '^$' | while read -r tag; do
+        crane tag "$REPOSITORY:@$(cat "$image_refs_file)" "$tag"
+    done
+fi
 
 filter='{
   "version": {"digest": $version}
 } | tostring'
-jq -r --null-input --arg version "$(sed 's/^[^@]*@//' < "$IMAGE_REFS_FILE")" "$filter"
+jq -r --null-input --arg version "$(sed 's/^[^@]*@//' < "$image_refs_file")" "$filter"
+
+rm -r "$oci_dir"
+rm "$image_refs_file"
+rm "$INPUT_FILE"