Ruby on Rails Expert needed for Backend Development

I am looking for a Ruby on Rails engineer to do update work on an existing application built in Rails 4. If you are interested please provide at least one past example of a rails app you have developed as the sole developer, and let me know what technologies were used in terms of database, hosting, and gems. Please also note that this is an urgent requirement, so it is important that you are available to begin work immediately and work through this weekend. Please acknowledge this when reaching out so we can be sure we're on the same page. Add a new API that allows users to post an "event" from the mobile app. Events can be one of three types: Automatic, Nutritional, or Exercise. Automatic: Already in the app, we need to re-use this model and preserve all existing data. The automatic approach links with credit card transactions (this component is already in place). The new feature in automatic is to pull in events using the Strava API, this is brand new and needs to be integrated from scratch, and merged in to the existing model while preserving all existing data. Nutritional: Nutritional info will come in as being tied to a business and we want to locate that business on Yelp and link to the Yelp Unique ID, and based on the category of the Yelp business, update a "health score" that specifies how healthy that restaurant is. Exercise: Exercise info will be a workout activity such as running, climbing, swimming, and a duration. This will also update a health score. We also want to add a new API to edit these events as well, a user should be able to update any non-automatic event. All events will include the date, a title, description, photo, category, and tie-in to an existing scoring system that links with the Yelp API and Strava API. The Yelp API is used to pull in a list of categories and match them against businesses the event occurred at In order to populate the mobile app with Yelp categories, we'll also need assistance in interfacing with the Yelp API, possibly a pass-through API call on the server that caches Yelp's list of available categories. We will need a new model added to support nested comments on Events, must also tie-in to existing model and preserve all data. We also need minor tweaks to the user's profile model and APIs to add a URL and text description. This should be simple, but keep in mind we must preserve existing data, so it's critical to use a migration that will back-fill existing users with empty strings for these values.