If you got a memory error on the rebuild then I’d add another GB of swap, though that’ll make your disk space issue tighter (It sounds like you’re on a small droplet with 25GB of RAM, which is just barely enough). I’d run a ./launcher cleanup
before each rebuild, or maybe you just have a bunch of backups and should move them to S3 ([Configure an S3 compatible object storage provider for uploads](Configure an S3 compatible object storage provider for uploads --you can do just backups, you don’t have to do all of the assets as described there).