Worked on move to AWS during and after Gilt acquisition by HBC, particularly on mobiles services, switched to work on application security later on.
Scala (with the emphasis on learning more functional programming) for services, unix tools / shell, make for 'glue', AWS-focused infrastructure (managed with terraform).
Worked on core components, architecture, automation, infrastructure, message queues, event streaming. Mostly Scala for services and libraries, Ruby, shell, make, etc for the rest.