Karolis is available for hire
Hire KarolisKarolis Ramanauskas
Verified Expert in Engineering
SQL Developer
Vilnius, Vilnius County, Lithuania
Toptal member since June 20, 2017
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
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-zyq9tI 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
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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