We have a lot of ECR repos that needed to be taken down, so I ran this little aws-cli + ruby + jq script to sanity check if all the images are old

require 'json'
repos = `aws ecr describe-repositories | jq .repositories[].repositoryName --raw-output`.split("\n")
pushed = repos.map do |repo|
  out = `aws ecr describe-images --repository-name #{repo} --output json --query 'sort_by(imageDetails,& imagePushedAt)[*]'`
  print '.'
  next unless image = JSON.parse(out).first
  Integer(image["imagePushedAt"])
end.compact
puts Time.at(pushed.max)