s3deploy

https://github.com/bep/s3deploy

A simple tool to deploy static websites to Amazon S3 and CloudFront with Gzip and custom headers support (e.g. "Cache-Control"). It uses ETag hashes to check if a file has changed, which makes it optimal in combination with static site generators like Hugo.

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If you're looking at s3deploy then you've probably already seen the aws s3 sync command - this command has a sync-strategy that is not optimised for static sites, it compares the timestamp and size of your files to decide whether to upload the file.

Because static-site generators can recreate every file (even if identical) the timestamp is updated and thus aws s3 sync will needlessly upload every single file. s3deploy on the other hand checks the etag hash to check for actual changes, and uses that instead.