This project archives reddit posts from the desired subreddit (r/combatfootage in my case) and writes the data to a postgres database. It then reads all the link submissions and downloads all videos to S3. This is configured to run update workflows once every 24 hours using a docker container on Fargate.
All of the infrastructure and setup, and deployment is automated using AWS CloudFormation. Initial setup of the database and archive is achieved by a bootstrap shell script executed by an EC2 instance that is terminated upon build success. All authentication uses custom AWS roles/policies which are created according to the principle of least priviledges. My monthly bill for all this is about $2 in infrastructure and currently around $3 for 4 months worth of archived videos in S3 standard-tier.