How to properly require aws gem

I'm trying to figure what to include in the require block in my rakefile (outside of the context of Rails) so that I can write files to S3. Currently, what I have is this (note that I am specifically using version 1):

require 'aws-sdk-v1'

But then I got this error:

LoadError: cannot load such file -- aws/s3

So then I added aws/s3:

require `aws-sdk-v1`
require `aws/s3`

But then I got this error:

LoadError: cannot load such file -- aws/s3/client

So I added the client:

require `aws-sdk-v1`
require `aws/s3`
require `aws/s3/client`

But then I got this error:

LoadError: cannot load such file -- aws/s3/bucket_collection

And so on. You get the idea.

Clearly, I'm not including whatever the appropriate base is. What is the correct require call in order to upload/overwrite a file on S3 in Ruby?