Oleksandr Zotov

I developed core applications for Ryanair, the biggest airline company in Europe by passenger count. These applications work under a high load of 19,000 employees and 45 million requests per month to the main website. I worked on FTL (flight time limitations) and Optimizer (automatic crew allocation by flight that complied with EU airline rules). I also maintained the current logic, implemented a new one, added unit, integration, and functional tests using a TDD approach, was responsible for the deployment scripts, and did tech reviews.
The system was made of a set of domain-driven and event-driven microservices and a WPF UI application made for crew controllers. Initially made on Azure and MS SQL infrastructure, we migrated it then to AWS and MySQL. Also, I designed and implemented a web API that was used by the main mobile application for cabin crew and pilots. I also developed the audit microservice which collected and presented the historical data from the other services.

The fintech startup Commitly built a liquidity planning application. I was the first front-end developer of the app and built it from scratch. I implemented the UI using Angular 4, Bootstrap, Sass, and HTML. We worked under the scrum methodology and as it was the startup, the main challenge was to understand business needs and the given graphic layout and then transform all of it into a flexible, scalable design and do it in a short time-frame. About a month after the start, they added a new front-end developer who I also mentored. After 11 months of development, we released the MVP.

Lionbridge is the marketplace for professional translators. Its back end has a microservice-based architecture built on top of the Azure Service Fabric platform.
The main business goal was to provide a sufficiently available, scalable, and flexible platform as it translates about 270 million words per month and is used by more than 1 million people. We achieved this by using Service Fabric features as well as smart partitioning and data replication.
I was responsible for the creation and maintainability of the services and the enforcement of the best practices for logging, error-handling, testing, and repository structure while following clean code principles. I also implemented the UI part of the application which was served as the bridge between translators and customers.

This system was designed for renewable power plants that gather data from turbines using specific drivers, sorts the information, stores it in an internal database, and provides a data analysis for the turbine operators on the UI.
My tasks were to maintain and improve both the back- and front-end sides of the application. I also wrote design documents, implemented new drivers and analysis modules, and improved the UX of the UI app.
Technologies: WCF, Silverlight, R