Andrei-Sorin Popovici, Developer in Oradea, Bihor County, Romania
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Andrei-Sorin Popovici

Verified Expert  in Engineering

Back-end Developer

Oradea, Bihor County, Romania
Toptal Member Since
September 14, 2022

Andrei is a back-end engineer with a degree in mathematics and computer science. He specializes in Ruby on Rails and is experienced in implementing, improving, and fixing complex business logic. He is also a pragmatic developer ready to use the best technologies for the job. Since high school, Andrei has proven to be a great problem solver, winning medals at national and international computer science contests and making the top 1% of participants in the Google Hash Code Qualification 2020.


Ruby on Rails (RoR), Ruby on Rails 5, React
Ruby on Rails (RoR), APIs, Payment APIs, Software Architecture, Full-stack...
Golf Genius Software
Ruby on Rails (RoR), CoffeeScript, Haml, Resque, RSpec, Factory Girl, Bootstrap...




Preferred Environment

MacOS, Linux, Jira, Slack, RubyMine

The most amazing...

...thing I've helped develop is the complex scoring engine at Golf Genius. I implemented features now used in live tournaments by the PGA and the USGA.

Work Experience

Ruby on Rails Engineer

2023 - PRESENT
  • Upgraded our application from Ruby on Rails 5.2 to 7.1.
  • Implemented a containerized version of our application.
  • Set up a parallelized test environment using Selenium Grid.
  • Contributed to our loyalty program as a full-stack engineer. Handled our Rails back end, React front end, and Android apps.
Technologies: Ruby on Rails (RoR), Ruby on Rails 5, React

Senior Software Engineer

2023 - 2023
  • Collaborated with many external partners in the integrations team, including McDonald's, Deliverect, Nana, and Albaik, addressing its unique challenges and requirements.
  • Completed integration and received certification from one of the biggest food business integrators.
  • Participated in the creation of a new service that will encapsulate integration logic from our business logic.
Technologies: Ruby on Rails (RoR), APIs, Payment APIs, Software Architecture, Full-stack, REST, Docker, Architecture, Sidekiq

Software Engineer

2021 - 2023
Golf Genius Software
  • Developed scalable new features for our complex scoring engine, which are currently used by major golf organizations such as the Professional Golfers' Association (PGA) and the US Golf Association (USGA).
  • Tracked and fixed bugs on Jira, quickly resolving top issues.
  • Wrote documentation for my features, recording specifications, reports, and feedback.
  • Contributed to multiple areas of our software, including report generation, APIs, integrations, and testing.
  • Conducted interviews and trained new employees as part of the recruitment team.
Technologies: Ruby on Rails (RoR), CoffeeScript, Haml, Resque, RSpec, Factory Girl, Bootstrap, Sass, Sharding, Data Structures, Algorithms, Ruby, HTML, JavaScript, REST APIs, RubyMine, Slack, Databases, Software Engineering, Code Review, Technical Hiring, Interviewing, React, B2B, Git, jQuery, API Integration, SQL, Back-end, PostgreSQL, Full-stack, APIs, REST, Software Architecture, SaaS, Architecture

Software Engineer

2022 - 2022
Zen Arbitrage
  • Tracked and fixed various issues, regardless of whether they were caused by bugs or AWS/Heroku infrastructure.
  • Created a new service that acts as a search engine that allows users to find reasonable offers on eBay easily. I worked on implementing filters and designs according to the specifications on Figma.
  • Redesigned and improved one of Chrome's extensions by adding new functionalities.
  • Added staging environments for all of our microservices.
  • Implemented integrations with Amazon Selling Partner (SP) API and Recurly. Also, I had to fix issues caused by some endpoints still being in beta.
Technologies: Ruby on Rails (RoR), Ruby on Rails 5, jQuery, Microservices, Sinatra, Elasticsearch, Heroku, Redis, SCSS, CSS, HTML5, HTML, Amazon Web Services (AWS), Agile, AWS Elastic Beanstalk, Amazon Merchant API, Amazon MWS, API Integration, SQL, Back-end, PostgreSQL, REST APIs, Full-stack, APIs, Payment APIs, REST, DevOps


2019 - 2020
  • Taught computer science fundamentals to high-school students or people looking to change their profession to programming.
  • Prepared students for the National Olympiad in Informatics by helping them improve their algorithmic thinking and problem-solving skills.
  • Helped people pass their technical or coding interview by teaching them how to approach problems and explain solutions to the interviewer.
Technologies: Algorithms, Data Structures, Interviewing, Technical Hiring, Mentorship

Application for Arbitraging Profitable Books

A web application based on microservices built with Ruby on Rails and Sinatra. This application allows a user to find profitable books on Amazon easily. I contributed primarily as a back-end developer though I also worked on some DevOps tasks. My main job was to convert the application from using Amazon's deprecated MWS API to the new and modern Selling Partner API. I fixed some issues related to Redis and ElasticSearch. I also helped the support team with questions regarding how some features should work based on the code.

Search Engine for eBay Offers

A SaaS application that allows users to easily search for offers that might be resold for a profit. We do this by offering them filtering options unavailable through eBay. I was a full-stack developer handling the Ruby on Rails back end and front end written with JavaScript, jQuery, SCSS, and the deployments.

Move Me - Renter Move Checklist

Move Me is a service adjacent to On-Site (RealPage's property management software). This service was designed to help future renters of the properties managed by On-Site. It provides the user with an easy-to-use interface where they can upload or check all the documents needed for a successful move.

As a Ruby on Rails developer, I upgraded the application from Rails 5.2 to Rails 7. This implied upgrading the Ruby version and all the gems to appropriate versions for this transition. I also set up a Docker image and deployment pipeline in Azure DevOps.
2017 - 2020

Bachelor's Degree in Mathematics and Computer Science

Babes-Bolyai University - Cluj-Napoca, Romania


REST APIs, jQuery, Sidekiq, Resque, Amazon MWS, React, Amazon Merchant API


Git, RubyMine, RSpec, Jira, Slack, Rake, Recurly, GitHub


Ruby on Rails (RoR), Bootstrap, Vanilla JS, Factory Girl, Sinatra, Ruby on Rails 5


Haml, CoffeeScript, Ruby, JavaScript, HTML, CSS, Sass, SCSS, HTML5, JavaScript 6, SQL, Python


PostgreSQL, Databases, Redis, Elasticsearch, MySQL


Microservices, REST, B2B, Agile, Continuous Integration (CI), DevOps, Back-end Architecture, Azure DevOps


AWS Elastic Beanstalk, MacOS, Ubuntu, Linux, Amazon Web Services (AWS), Heroku, Docker


Data Structures, Algorithms, Back-end, Mathematics, Code Review, Technical Hiring, Interviewing, Source Code Review, Responsive UI, Bootstrap UI, API Integration, Full-stack, APIs, Software Architecture, Sharding, Operating Systems, Software Engineering, Turbolinks, Mentorship, Payment APIs, SaaS, Architecture, Software as a Service (SaaS)

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