You can now delete artifacts that you no longer want stored on Buildkite with the new delete button in the Artifacts tab:

When you delete an artifact, it's permanently deleted from our AWS S3 storage and removed from the job’s artifact list. If you’re using your own S3 bucket or Google Cloud Storage bucket for artifact storage, you'll need to manually remove them from your artifact store (don’t worry, we'll remind you to do this in the confirmation message).

If you’re performing deletions over a large number of builds, or wanting to automate deletion in general, we've updated the REST APIs to add support both artifact deletion and job log deletion.