Aleksandar Kostic

Available to hire

Senior full-stack developer with 9+ years of building innovative solutions that enhance project outcomes and functionality.

About

Senior full-stack developer with 9+ years of building innovative solutions that enhance project outcomes and functionality.
I specialize in HTML, css, javascript, React.js, Next.js, tailwind css, material-ui, bootstrap with frontend and secure, flexible backend.
Experience:
-Led the end-to-end development of a high-traffic web application serving over 1M users, optimizing frontend performance with Next.js server-side rendering (SSR) and reducing page load times by 50%.
-Architected and implemented a scalable microservices infrastructure, migrating from a monolithic system to containerized Node.js services on AWS ECS, which improved system reliability and reduced downtime by 40%.
-Optimized PostgreSQL database queries using indexing and partitioning techniques, improving read/write efficiency by 30% and reducing query execution time from 200ms to 50ms.

As an available full-stack developer, I can work more than 8 hours a day if needed. I will provide company with outstanding result. Thanks.

  • Joined March 2025

Languages

  • EnglishAdvanced
  • SerbianFluent

Industry experience

  • Software & Internet
  • Professional Services

Projects · 1

This project is an investment website containing two services.
Quant Invest: Leverages on-chain quantitative algorithms to automate user’s crypto investments.
Private Club: This provides an exclusive network, shared strategies and unique opportunities.
This project consists of a responsive front-end and a back-end that is thoroughly secured and is supported by blockchain technology.
You can check out on https://www.twine.net/signin
Thanks.

  • Blockchain Developer
  • Full Stack Developer

Education

Bachelor in Computer Science · Singidunum University2014 – 2019

Certifications and awards

Senior Full-sta2025

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