Kostantinos Leloudas

Contribute to the development and optimization of the company’s sportsbook platform using modern technologies such as Tailwind, Vite, Vue, Vuex, Vitest and Storybook. Collaborate with cross-functional teams to deliver high-quality, maintainable code, focusing on performance, accessibility, and scalability (mobile and web). My responsibilities included implementing new features, maintaining state management, writing comprehensive unit tests, and ensuring a seamless user experience for millions of users in a fast-paced, agile environment.

Worked on the development, maintenance and optimization of several products ( e.g Roulette, Blackjack ), using Typescript, React, Redux, SignalR, RxJS, webpack and Jest.

Collaborated with cross-functional teams to implement solutions that enhanced both Web Vitals metrics and accessibility, ensuring high performance and usability for all users, both for the mobile and web platforms.

Worked on the development and maintenance of several projects. Amongst them, Portlux, is a web application operating in Sweden built with Symfony, thus using PHP, PostgresQL on the backend, and javascript, twig, react on the front.

HazDash is another web application developed from scratch using React, TypeScript, GraphQL and Node.js with a microservices architecture, deployed through Docker. I was the primary Git contributor, responsible for over 50% of the codebase, and played a key role in designing and implementing core features throughout the project lifecycle.

Progressive single page apps development with React/Redux.

RESTfulAPI development and data modeling. Built around PostgreSQL and MongoDB.

Cloud Infrastructure deployment on AWS. Utilized EC2 instances for horizontal

scalability.

Integrated API with Google's geolocation and places API to build Search Engine