Jan Zych

Involved in designing and developing the web pages using HTML 5, SASS, React JS, Redux, Flux, Node JS, CSS, TypeScript, Java Script, Bootstrap, Node.js, NPM, Mongo DB. Performed Unit testing on React JS applications using tools like Enzyme and Cypress. Worked at Rentz Group as a freelancer, to build several web projects collaborating closely with designers, and backend developers to implement seamless and visually appealing web applications.

Optimize search engine for Elastic Search Document Restful API's using Swagger for internal use Integrate with MongoDB, CassandraDB and PostgreSQL Experience in web applications development using Django (Python) and Beego (Golang) Maintain and develop frontend source of ReactJS Experience with Docker containers and deploy application containers

High-load big data system which provides a full package of services for working with advertisement on the Internet: a dashboard for convenient creation of thousands of ads on more than 10 various platforms and tracking their performance, sites to which these ads lead traffic, machine learning services to predict revenue and spend in real-time and accordingly edit bids of ad companies on the basis of dozens of metrics and trends.

Designed RESTful APIs using Ruby on Rails to handle client-server ommunication. Implemented authentication and authorization mechanisms using Devise or custom solutions. Created database models and migrations using ActiveRecord for PostgreSQL or MySQL databases. Developed CRUD (Create, Read, Update, Delete) functionality for managing application data.