HTTP to S3 cache hostable on Heroku
curl http://your-cache-host.herokuapp.com/http://foobar.com/path/to/package.tar.gz
heroku create --buildpack git://github.com/kr/heroku-buildpack-go.git
heroku config:add AWS_ACCESS_KEY_ID=somekey AWS_SECRET_ACCESS_KEY=some-secret-key S3_BUCKET_NAME=http-cache-test
git push heroku master
Support cache invalidation
Add basic auth to access the proxy
Server /robots.txt and / directly.
Support files bigger than 5GB
Use Multi-Part uploads to S3 for big files
Add support for redirects to S3 signed urls