Sr. Ruby on Rails - Fullstack developer

 Everlyhealth: Senior Backend Engineer Jan 2022 — Feb 2023

As part of an architecture team I helped upgrade a large Ruby on Rails application. Then I became the team leader of four engineers in this team, I debugged six Rails, React, and Gatsby applications and also helped design and partially implement integration with a third-party vendor to save 200K USD a year.

Responsibilities:

• Maintain an extend Ruby On Rails, React, Gatsby applications.
• Work with Product Managers and stakeholders to prioritize, define and implement technical solutions.
• Lead the technical team: unblocking them, helping them complete assignments, estimate tasks and choose, and push them to excellence.

Projects:

• Ruby On Rails upgrades

With 90% of our applications using outdated versions of Ruby On Rails, the risk of being unable to receive security updates grows daily. It becomes harder to use new libraries and take advantage of the latest features of the framework.
I joined a backend Architecture Team to solve this problem for all our applications:

1. My team increased the test coverage to 90% and reduced the test suite run time by half.
2. My team upgraded to the next major Ruby On Rails version of our target applications.
   

• Third-Party Vendor integration

To save around 200k USD a year, we changed our manufacturing and shipping vendor for a category of products.

My team modified the critical ordering placement process across multiple Ruby On Rails services to comply with the new vendor and achieve the expected savings.

Technologies: Jira, Ruby on Rails, Ruby, React, Gatsby, PostgreSQL, Spree commerce.

Tandem: CTO/Founder Nov 2017 — Dec 2021

Successfully Forked the (Ruby on Rails) Aliada codebase and transformed it to a B2B supply and cleaning services platform.

Responsibilities:

• Maintained and extended the React customer front-facing and operational administration web for three years alongside the Rails app using GraphQL and Apollo.

Projects:

• Pivot to B2B

With a dwindling bank account and no compelling story for our investors to raise another round. We explored focusing on our most profitable clients: businesses.

• Worked with the team to define an MVP to the last detail. Estimate it and execute it in less than a month.
• Thanks to an impressive demo of the MVP we signed a new large customer that saved the company and gave us a compelling case for another round of investment.
• The MVP quality was so high that engineers were happy to keep investing in it. We implemented new technologies like GraphQL and the latest React version.
• New features the team implemented:

• Two payment(STP, Stripe) gateways working as a fallback in case of a charge rejection.
• A new ordering flow customized for recurrent purchases.
• A new mobile application written in Kotlin that allowed a small ops team to manage more than 200 cleaners' schedules and location-based check-ins
• A new custom extensible administration system written in React.

• Enterprise client ERP integration

Our largest customer payment process took a lot of effort and time and was error prone. We could streamline our process and, at the same time, raise the bar for competitors by integrating with the customer system.

Our customer used Mulesoft as a middleman between the vendors and their Workday ERP system.

• I implemented the cXML standard for business e-commerce on our main Ruby On Rails and React applications.
• We provided a seamless experience to our customer employees by allowing them to use our platform but finishing the process on their own system.
• We reduced the errors and manual work in the payment process to almost zero.

• Implement Permissions and Roles for our end-users

To better match our customer's organizational hierarchy of responsibilities and give them more control of their purchases in our system, we implemented a two-role permissions system.

• I refactored our e-commerce React frontend and Ruby On Rails backend to enable and disable features depending on the role and permissions.
• With this refactor in place, it was easy to create the following features:

• A monthly budget feature per location.
• An order approval process.
• Blocking editing key organization details.
• An invite system to bring more of our customer employees into our system.

• Odoo ERP migration

With a reduced tech department to 1 individual(me) it became a priority to minimize the systems we maintained, so we transferred responsibilities to the flexible and open-source Odoo ERP.

• I Implemented a REST API in Python inside Odoo to talk to our Ruby on Rails backend.
• Created a real-time synchronization of our ordering, shipping, products, customer and invoicing systems into Odoo. We executed a slow migration of these responsibilities without operations disruption.

Technologies: Jira, Ruby on Rails, React, Apollo, GraphQL.

Aliada: CTO Jan 2015 — Nov 2018

Built a team of 5 developers implementing Scrum and Agile practices and with them grew the marketplace 10x.

Responsibilities:

• Create the technological infrastructure to help companies become more profitable, starting with our own.
• Build an excellent tech organization with a strong team committed to developing their skills
• Represent the technology part of the business on strategic business decisions with a strong understanding of the business side
• Make sure the organization can rapidly, reliably and repeatedly deliver a quality product to the market

Projects:

• Build the post-MVP version

After validating the marketplace for the home cleaning service business model with a cheap MVP the company tasked me with building a new backend API and frontend experience.

• Fully migrated to the new Ruby on Rails and knockout.s applications in 6 months.
• Greatly expanded the original feature set:

• A new initial experience that included choosing from real-time availability of our cleaning providers (Aliadas).
• A fully automated billing system.
• The ability to modify the booked services with pre-defined penalizations.
• A new home page.
• An automated test suite with over 90% coverage.

• Support 10x growth

The company enjoyed accelerated growth in the second year of operations but we wanted to avoid over-hiring in customer support by automating as many processes as possible and by providing tools to empower our existing staff to do more faster.

• Built and evolved an administration back-office tool.
• Added dozens of rules and automated user flows to resolve issues automatically or prevent them.
• Refactored our matching algorithm to support zoning and various characteristics(skills, rating, etc) while maintaining good performance for this key user flow.
• We reduced the incidence handling to less than 2 percent of the services.

• Build the engineering team

To support the 10x company growth I was tasked with building a world class engineering team.

• I defined job positions, hiring pipeline and review process.
• Hired a team of 5 excellent senior engineers.
• Defined a career ladder to promote engineers.

Technologies: Github Projects, Git, Github, Ruby on Rails, Knockout.Js, React.

Crowd Interactive: Backend Engineer Sept2014 — Jan 2015

Staff augmented the Zoobean team to work on the books-recommendations-for--children-platform built on Ruby on Rails.

Responsibilities:

• Function as a member of our client’s engineering teams following their practices and requirements.

Projects:

• Add multi-tenancy to an existing Ruby On Rails application

The client wanted to give each user their subdomain user.client.com while ensuring data isolation.

• We implemented a multi-tenancy architecture using PostgreSQL schemas to isolate each customer's copy of the database.

• Improve the recommendation algorithm

The client wanted to make sure that we were suggesting books according to the children’s age.

• We modified the existing algorithm written in Ruby to handle the new use case along with other 30 parameters.

Technologies: Pivotal Tracker, Git, Ruby on Rails, PostgreSQL

Bebitos: CTO April 2014 — Aug 2014

Software maintenance for Spree(a Ruby On Rails Engine) Merchant-based e-commerce with focus on conversion and operations tools development.

Responsibilities:

• Maintain and extend the Spree-based e-commerce Ruby on Rails application.

Projects:

• Improve the performance of the e-commerce application.

The site grew in the number of products exponentially during the first years of operation, but little work was done to improve the user experience up to that point.

• I used Memcache to implement Russian doll caching and improve response times by almost 50%
• Created new types of promotions.
• Streamline the importing of products from a manual process to a completely automated one using CSV files.
• Transitioned the technology and data to the new Owner’s systems, writing a data migration script.

Technologies: Pivotal Tracker, Git, Ruby on Rails, Ruby, Memcache, Spree commerce

Bandtastic: CTO Jul 2011 — August 2014

Created and maintained the backend(on Django) and the frontend(jQuery) for a crowdfunding platform, the ticketing system, and spin-off for VIP tickets.

Responsibilities:

• Build the initial version of the product.
• Lead the technology efforts and eventually a an engineering organization

Projects:

• Build a Crowdfunding for concerts ticketing system

The whole idea of the company was to get fans together to bring their favorite artists to their cities. As the only engineer of the company I had the responsibility to implement the frontend and backend and any support systems.

• I learn how to build a real production webapp and build it in less than 6 months, ready for a big launch event we arranged with a sponsor. This platform included:

• Deployment to Heroku.
• Social login
• A pledge payment system to get the money only if a campaign succeeded.
• A backoffice to completely define and manage a crowdfunding project.
• A system of rewards.
• A ticketing system to do the check-ins on the day of the event using QR codes and a custom mobile application.

• We managed to crowdfund 15 concerts in a couple of years.

• Fork our ticketing system for VIP concerts

We negotiated a deal with a partner that was impressed by our technology and wanted to use it for their own private concerts.

• Completely re-designed the look and feel of the frontend without changing the backend.
• Tunned the application performance to support flash sales using heavy caching and database locks.

Technologies: Trello,, Git, Github, Django, Python, RabbitMQ, PostgreSQL, Heroku