Roman is available for hire

Roman Horodianenko

Verified Expert in Engineering

Software Development Developer

Warsaw, Poland

Toptal member since October 26, 2021

Expertise

Software Development Decentralized Finance (DeFi)JavaScript CSS TypeScript React.js MacOS Node.js Redux Next.js GraphQL Tailwind CSS

Bio

Roman has over seven years of experience in large-tech Web2 and futuristic Web3 products. He is passionate about crypto and decentralized finance and enjoys exploring various EVM blockchains and L1s/L2s. He is currently diving into the world of building smart contracts using Solidity. He is keen on immersing himself in the Web3 and the crypto space. Roman prefers crafting clean code within flexible architecture, collaborating in small teams, and using simple processes for efficiency.

Portfolio

GoodEntry.io

React, TypeScript, Chakra UI, Tailwind CSS, React Query, Ethers.js, Emotion...

Thetanuts Finance

React, TypeScript, React Query, Ethers.js, Styled-components, CSS...

TikTok

TypeScript, React, CSS

Experience

Software Development - 6 years
JavaScript - 6 years
TypeScript - 4 years
Node.js - 4 years
React - 4 years
Styled-components - 2 years
React Native - 1 year
MobX - 1 year

Availability

Full-time

Preferred Environment

MacOS, WebStorm

The most amazing...

...interfaces I have developed were for well-known social network app companies, like Snapchat and TikTok.

Work Experience

Front-end Lead

2023 - PRESENT

GoodEntry.io

Collaborated with GoodEntry.io as a front-end lead.
Built user interface for on-chain day trading derivative exchange.
Led a team of two junior/middle front-end developers.

Technologies: React, TypeScript, Chakra UI, Tailwind CSS, React Query, Ethers.js, Emotion, Next.js, CSS, Decentralized Finance (DeFi)

Front-end Lead

2022 - 2023

Thetanuts Finance

Worked with Thetanuts Finance as a front-end lead.
Built user interface for decentralized option vaults (DOVs).
Led a team of three front-end junior and middle developers.

Technologies: React, TypeScript, React Query, Ethers.js, Styled-components, CSS, Decentralized Finance (DeFi)

Front-end Engineer

2021 - 2022

TikTok

Developed several internal and external web interfaces.
Increased DAU to 110,000+ on several interfaces that I developed.
Successfully communicated with distributed teams in different time zones and countries.

Technologies: TypeScript, React, CSS

Front-end Engineer

2020 - 2021

Snap Inc.

Developed a React app without Redux or any other state manager libraries.
Created the infrastructure for using a micro-front-end approach.
Integrated micro-front-end app with the larger web system.

Technologies: TypeScript, React, Redux, CSS

Front-end Engineer

2019 - 2020

Yalantis

Contributed to the development of a USA company that is the leader in the real-estate sphere.
Built a React app with Apollo Client instead of Redux.
Developed a back-end for front-end architecture (BFF) service based on Apollo Server.

Technologies: TypeScript, GraphQL, React Apollo, Apollo Server, React Native, CSS

Senior Front-end Developer

2017 - 2019

PrivatBank

Developed a real-time chat client for the LiqPay payment system.
Built a transport library with an offline mode based on WebSocket protocol.
Developed a cross-platform forms constructor for building interfaces without code.

Technologies: JavaScript, TypeScript, React, Redux-Saga, CSS

Front-end Developer

2016 - 2017

Poster

Developed the core system for a client's POS application.
Optimized system performance for faster communication between different clients.
Improved the development process, enabling advanced use of existing tools and implementation of new ones.

Technologies: JavaScript, React, CSS

Experience

GoodEntry.io

Good Entry is an on-chain derivative exchange enabling leveraged day trading with built-in downside protection, built on top of Uniswap v3. Liquidity providers earn swap and trading fees without counterparty risk.

Thetanuts Finance

https://thetanuts.finance/

Thetanuts Finance is a decentralized on-chain options protocol focused on altcoin options, allowing users to go long or short on on-chain options. I was building the user interface for the decentralized option vaults (DOVs). Led a team of three front-end developers.

Poster POS

https://joinposter.com/en

A web-based app that handles sales and manages POS inventory, finances, and analytics.

As a front-end developer, I built a lot of features, like product modification or protocol for communication with a device built on a Raspberry Pi.

I also worked with the analytics part of the app, including counting profit, income, leftovers, and several other indicators.

PrivatBank

PrivatBank is one of the biggest banks in Ukraine.

I was a front-end engineer and developed real-time chat for the LiqPay payment system. I also developed a transport library for this chat.

I also gained experience with developing a no-code cross-platform solution for building interfaces that were runnable on the web, Android, and iOS.

Education

2018 - 2020

Master's Degree in Computer Engineering

National Technical University of Ukraine "Kyiv Polytechnic Institute'" - Kyiv, Ukraine

Skills

Libraries/APIs

React, Node.js, MobX, Redux-Saga, React Query, Emotion

Tools

WebStorm, React Apollo

Languages

TypeScript, JavaScript, HTML, CSS, GraphQL

Platforms

MacOS

Frameworks

Redux, Next.js, React Native, Tailwind CSS

Other

Software Development, Styled-components, Decentralized Finance (DeFi), Apollo Server, Ethers.js, Chakra UI

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