I have experienced some silent failures while trying to use nix copy to an s3 bucket via an http proxy. Connecting to the bucket directly worked ok.

I was alerted to this issue: aws/aws-sdk-cpp#1049 .

The Aws SDK doesn't implicitly respect http_proxy and the like. Could this be related?

The silent failure is probably an unrelated problem, but it's hard not to talk about them at the same time. :)