Karolis Ramanauskas, Developer in Vilnius, Vilnius County, Lithuania
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Karolis Ramanauskas

Supabase Developer

Vilnius, Vilnius County, Lithuania

Toptal member since June 20, 2017

Expertise
JavaScriptReact.jsTypeScriptExpress.jsGraphQLSolidityNext.jsSQLTailwind CSSThree.js
Bio

Karolis is a curious senior full-stack engineer (frontend-leaning) and a builder at heart. He enjoys converting ideas into digital products. Karolis operates at the intersection of engineering, design, and product. He's worked at a wide range of companies, from small startups to big corporations such as Volvo Cars and Uber.

Portfolio

Lattice
React, Next.js, TypeScript, Three.js, Solidity
0xMacro
Solidity
Volvo Cars
JavaScript, GraphQL, Next.js, TypeScript

Experience

  • JavaScript - 10 years
  • SQL - 10 years
  • React - 8 years
  • Next.js - 5 years
  • Solidity - 5 years
  • Supabase - 5 years
  • Tailwind CSS - 4 years
  • TypeScript - 4 years

Preferred Environment

React, Next.js, TypeScript, Tailwind CSS, Framer Motion, Three.js, GSAP, Supabase, Solidity

The most amazing...

...thing I’ve done was build tools that ensured the reliability of Uber services—these have been used by over 3,000 engineers around the globe.

Work Experience

Senior Full-stack Developer

2024 - 2026
Lattice
  • Contributed to the core open-source MUD framework, helping build an engine for large on-chain applications.
  • Designed and implemented World Explorer, a data exploration tool.
  • Contributed to DUST 3D game client and related tooling, such as development SDK. Implemented in-game apps.
  • Maintained and developed all company websites, including bridge, docs, and other initiatives.
Technologies: React, Next.js, TypeScript, Three.js, Solidity

Security Auditor

2023 - 2023
0xMacro
  • Participated in security audits of production Solidity smart contracts through manual code review.
  • Implemented unit and fuzz testing strategies to identify and mitigate vulnerabilities.
  • Dove deep into production systems for protocols such as ThirdWeb, Synthetix, and PoolTogether.
Technologies: Solidity

Principal Web Developer

2020 - 2022
Volvo Cars
  • Developed and optimized web components for Volvo Cars' design system.
  • Led the development of a custom CMS and internationalization platform.
  • Introduced best practices for team collaboration and sped up shipping velocity.
Technologies: JavaScript, GraphQL, Next.js, TypeScript

Software Engineer

2018 - 2020
Uber
  • Developed internal observability tools supporting incident detection and mitigation.
  • Built data-driven React interfaces and improved system reliability through instrumentation and error monitoring.
  • Learned how to be effective within a big organization, improved collaboration, presented ideas, and shipped products within a team.
Technologies: GraphQL, React

Freelance Software Engineer

2017 - 2018
Toptal Clients
  • Handled projects involving Ethereum smart contract development.
  • Learned how to effectively work with clients, gather requirements, and come up with a desirable solution.
  • Gained a lot of exposure to Google Analytics and how it can be used to drive a website's performance.
Technologies: Express.js, Solidity, React

Experience

ETHGlobal Istanbul (1st Place)

https://ethglobal.com/showcase/uniroll-zyq9t
I won 1st place in the CoW Programmatic Framework track, as well as integration prizes in WalletConnect and Gnosis Chain tracks. The project was a payroll system for making payments across any chain of the user's choice and in any currency, with the CoW protocol automatically performing currency conversion on behalf of the beneficiary's choice.

Hack4Vilnius (1st Place)

https://hack4vilnius.lt/nugaletojai/2024-m-nugaletojai/
Hack4Vilnius is a 3-day hackathon with the aim of improving Vilnius City. Our solution (https://idejavilniui.lt/), a citizen engagement platform, won 1st place, 1,500 EUR in prizes, and future mentorship.

Education

2013 - 2016

Bachelor of Science Degree in Computer Science

Lancaster University - Lancashire, UK

Certifications

JULY 2018 - JULY 2019

Google Analytics Individual Qualification

Google

Skills

Libraries/APIs

React, Framer Motion, Three.js, GSAP

Languages

JavaScript, TypeScript, GraphQL, Solidity, SQL

Frameworks

Express.js, Next.js, Tailwind CSS

Other

Supabase

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