AWS Elastic Container Registry costs tend to grow over time - the more images you store, the higher the cost. There are ready-to-use solutions like ECR lifecycle policies but they are not checking if the images are still being used - it can be dangerous for your applications' health! We decided to write our own ECR cleaner. It checks if images are still used by ECS, Lambda, or App Runner before removing: https://github.com/devopsbox-io/aws-ecr-cleaner This is another useful tool that we are publishing for free, enjoy!

very useful, cost isn't something we optimise for but I've occasionally hit account limits e.g. 10,000 images per repository

If it can interest other people, at Qovery, we're building Pleco. Helping you to wipe various kind of Cloud providers objects based on several elements (tags, tags with a TTL etc...). https://github.com/Qovery/pleco. Hope it can help