Hello @sike
you can in fact go around oidc by using the frontend login endpoint. Have a look at our cells-sdk-go code here (https://github.com/pydio/cells-sdk-go/blob/master/transport/oidc/tokens.go#L121) you do not need to handle the full oauth flow in that case.
Once you have the token yes you should be able to use your AWS SDK by providing the token as the Access Key and “gatewaysecret” (fixed string) as the Secret.