I worked on mostly backend contracts (primarily in node.js, Ruby/Rails, Postgres, MongoDB, Chrome extensions, JavaScript) and also some frontend contracts using React.
A few projects include: building a Ruby port of a universal API that supports many popular services, building a real estate calculations library for mobile/web apps, building a Chrome extension to track browser activity, building a portal frontend for managing users/teams and OAuth2 integrations, completing a podcast site backend with a model-based framework, writing a migration that requires making REST calls and uses IronWorker, and improving a backend's integration with Shopify and BigCommerce storefronts.
