set -euo pipefail
example_work=$(mktemp -d "${TMPDIR:-/tmp}/jq-yq-example.XXXXXX")
trap 'rm -rf -- "$example_work"' EXIT
cd "$example_work"
mkdir data
cat > data/base.yaml <<'JYQ_INPUT_1'
service:
  name: api
  replicas: 1
  labels: {app: demo}
  ports: [80]
JYQ_INPUT_1
cat > data/overlay.yaml <<'JYQ_INPUT_2'
service:
  replicas: 3
  labels: {owner: lab}
  ports: [443]
JYQ_INPUT_2

yq -o=json -I=0 '. + load("data/overlay.yaml") | .service' data/base.yaml