Deputyl is your little helper, that runs inside a kubernetes cluster, discovers all running pod images and tags and checks the docker registry for newer semver tags. It then reports newer versions as a prometheus metric for each container.
deputyl_newer_patch_versions{namespace="default",pod="server",repository="nginx:16.0.0"} 3
deputyl_newer_minor_verions{namespace="default",pod="server",repository="nginx:16.0.0"} 1
deputyl_newer_major_versions{namespace="default",pod="server",repository="nginx:16.0.0"} 0