Nikolai Mitriashkin, Developer in Roseville, CA, United States
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Nikolai Mitriashkin

Verified Expert  in Engineering

Front-end Developer

Roseville, CA, United States
Toptal Member Since
September 19, 2022

With almost a decade of experience as a JavaScript developer, Nick specializes in creating web applications on Next.js, React, and TypeScript. His expertise lies in optimizing code performance and delivering complex features with minimal tech debt that aligns with top industry standards.


International Travel Agency
TypeScript, JavaScript, React, Next.js, GraphQL...
Domain Money LLC
React, CSS, TypeScript, Single-page Applications (SPA), JavaScript, APIs...
TypeScript, Rust, React, Electron, MobX, HTML, Next.js, Algorithms, Agile...




Preferred Environment

React, Node.js, TypeScript, Next.js

The most amazing...

...tool I've built is an automated trading system on top of the Steam API, which generated more than $200,000 of revenue fully on autopilot.

Work Experience

Senior Front-end Developer (via Toptal)

2023 - 2024
International Travel Agency
  • Created a standalone tool that leverages the ChatGPT API to replace CSS-in-JS with CSS modules around the codebase automatically.
  • Reduced the webpack bundle size by around 200 kilobytes (33%) by refactoring the codebase to increase page loading speed.
  • Improved the new Core Web Vitals metric INP by adding visual feedback to the interactions while the app is in the loading state.
  • Improved the developer experience with CSS modules by replacing an inefficient, outdated npm package with a solution native to Next.js.
  • Rebuilt the old Apollo GraphQL middleware to be compatible with the new URQL client.
  • Replaced several npm packages with simpler custom solutions to reduce script evaluation time.
  • Upgraded React to the latest major version (18.2.0).
  • Contributed to numerous minor features and bug fixes.
Technologies: TypeScript, JavaScript, React, Next.js, GraphQL, Search Engine Optimization (SEO), ChatGPT API, On-page SEO, Technical SEO, Website Audits, Architecture, Web Development, Sentry, API Integration, Redux Toolkit, Front-end Architecture

Senior Full-stack Developer

2022 - 2023
Domain Money LLC
  • Revamped critical user flow, reducing drop-off by 7%. Achieved faster loading, simplified interactions, and modernized design for an enhanced UI.
  • Engineered the funding flow for goal-based portfolio allocation. Streamlined the setup with personalized recommendations, allowing users to customize frequency, funding source, and amounts for seamless investment management.
  • Created dynamic conditional flows, delivering personalized user experiences based on previous selections.
  • Utilized Next.js to optimize load times and leverage powerful dynamic routing for seamless navigation.
Technologies: React, CSS, TypeScript, Single-page Applications (SPA), JavaScript, APIs, Fintech, Back-end, PostgreSQL, Next.js, React Redux, Firebase, Node.js, Integration, SQL, Stripe, Architecture, Web Development, Amplitude, Sentry, Stripe API, API Integration, Redux Toolkit, Front-end Architecture

Front-end Lead

2020 - 2022
  • Developed an internal CCTV dashboard for live viewing in warehouses, featuring date/time selection, export, and motion detection. Deployed to enhance security and efficiency for hundreds of workers.
  • Restructured the checkout page, resulting in a significant reduction in registered errors and, as a result, a nearly 1% increase in user completion rate.
  • Led a team of four front-end engineers, enabling their professional growth. Simultaneously served as a tech lead on multiple infrastructure projects.
  • Integrated a 3rd-party open-source solution, Appium Inspector, into an Electron application.
  • Designed new process to generate reports simplifying UI tests.
Technologies: TypeScript, Rust, React, Electron, MobX, HTML, Next.js, Algorithms, Agile, Confluence, English, CSS, Linux, Formik, HTML5, CSS3, JavaScript, A11Y, Node.js, PostgreSQL, REST, Object-oriented Programming (OOP), Design Patterns, Figma, Jest, Antd, Sass, SCSS, Webpack, Single-page Applications (SPA), APIs, Back-end, React Redux, Tailwind CSS, Technical Leadership, Team Leadership, Cross-functional Team Leadership, Amazon Web Services (AWS), Full-stack, Docker, Integration, SQL, eCommerce, Ruby on Rails (RoR), Python, Architecture, Web Development, Ant Design, Sentry, API Integration, Material UI, Redux Toolkit, Front-end Architecture

Senior Full-stack Developer

2019 - 2020
Con Certeza
  • Designed and developed a portal for out-of-school teachers to help them find their audience and share their knowledge.
  • Built Social Networks parser using Node.js, TypeScript, and PostgreSQL. Automated scraping from LinkedIn, Facebook, and Telegram channels while handling anti-scraping restrictions.
  • Refactored a legacy codebase of a React-based parental control app. Migrated everything to TypeScript and Next.js.
  • Built a React-based front end for a few public web services.
  • Created a Figma design document for an organization catalog and converted it to HTML.
Technologies: JavaScript, TypeScript, React, Redux, Next.js, HTML, jQuery, Agile, Gulp, English, CSS, Formik, HTML5, CSS3, PHP, A11Y, Node.js, TypeORM, PostgreSQL, Telegram Bot API, REST, Figma, Sass, SCSS, Webpack, Single-page Applications (SPA), APIs, Back-end, Python, Front-end, GitHub, Docker, Express.js, React Redux, SEO Tools, Technical Leadership, Amazon Web Services (AWS), Scraping, GraphQL, Apollo, Integration, SQL, Architecture, Web Development, API Integration, Material UI, Front-end Architecture

Full-stack Developer

2017 - 2019
  • Developed and maintained a React-based front end for an educational portal.
  • Built an interactive map for a real-estate company.
  • Developed a CMS plugin, allowing managers to edit a text entry.
  • Built a complex tourism site with multiplying JavaScript animations and transitions between pages using only JavaScript.
  • Developed and maintained an extensive plumbing web catalog.
  • Converted a few dozen Figma, Adobe Experience Design (XD), or Adobe Photoshop design documents into themes for WordPress, Bitrix24, Drupal, or Joomla sites.
Technologies: jQuery, JavaScript, HTML5, SCSS, Node.js, React, HTML, Agile, Gulp, MySQL, English, CSS, CSS3, PHP, WordPress, 1C Bitrix, Drupal, A11Y, TypeORM, PostgreSQL, REST, Object-oriented Programming (OOP), Figma, Adobe Photoshop, Sass, Webpack, Single-page Applications (SPA), APIs, Back-end, Front-end, GitHub, React Redux, SEO Tools, Scraping, GraphQL, Apollo, CRM APIs, Integration, Redis, SQL, Search Engine Optimization (SEO), On-page SEO, Technical SEO, Website Audits, Web Development, API Integration, Front-end Architecture

Full-stack Developer

2016 - 2017
  • Implemented an algorithm to autogenerate prices based on market trends.
  • Created an automatic web scraper to collect data from various public resources.
  • Developed a small social media website to allow a free promotion of different stuff.
  • Integrated an open-source Steam authorization PHP library into the project.
  • Implemented a simple object-relational mapping (ORM) tool to handle complex queries instead of sending thousands of queries using CMS.
Technologies: JavaScript, PHP, MySQL, OAuth, Steam Web API, HTML, jQuery, Gulp, CSS, HTML5, CSS3, WordPress, Adobe Photoshop, Sass, SCSS, Webpack, Front-end, GitHub, User Interface (UI), SEO Tools, Full-stack, Scraping, Integration, Redis, SQL, Search Engine Optimization (SEO), On-page SEO, Technical SEO, Website Audits, Web Development, API Integration, Front-end Architecture

eCommerce Website
This is a plumbing catalog based on the PHP framework. As a sole front-end developer, I developed the whole project using HTML, JavaScript, CSS, and jQuery. Although this was a simple project, it involved a large amount of work because of the number of pages and the amount of detail that I needed to pay attention to.

Tourism Website

I was a front-end engineer working on this WordPress-based website. My job was to convert the XD design document to HTML. The interesting part was making image maps interactive without using a framework. I also performed the customization of Google Maps.

Educational Portal

This is a server-side rendering (SSR) application with a REST back end. I designed and implemented the whole solution, including the public and private parts. The main task was to create and approve the complex user role model, while everything else was pretty straightforward.

Video Monitoring Solution

This is a private video-streaming portal for internal company operators to monitor the situation in storehouses online. As a front-end developer, I implemented a video player and a set of features for its timeline panels, such as the video export of a chosen date and time range, video preview on the mouse hover, an intuitive timeline scale on the mouse wheel, player synchronization, and more.

Personal Blog
A technology-focused blog mainly targeting freelancers in the tech industry.

The website's core is the latest Next.js, which uses a headless WordPress API behind the scenes.

These simple technologies and best practices helped achieve a solid 95-100 points on Google Page Insights and a seamless user experience.
2007 - 2011

Bachelor's Degree in Engineering

Industrial University of Tyumen - Tyumen, Russia


React, Redux-Saga, Formik, Redux Form, MobX, Node.js, Antd, jQuery, Steam Web API, React Redux, Stripe, Stripe API, Telegram Bot API, Google Maps


Figma, Confluence, Sentry, Redux Toolkit, Adobe Photoshop, Webpack, Gulp, GitHub


Redux, Next.js, Tailwind CSS, NestJS, Ant Design, Material UI, Electron, Jest, Express.js, Ruby on Rails (RoR)


HTML5, CSS3, JavaScript, TypeScript, Sass, SCSS, HTML, CSS, GraphQL, PHP, Python, SQL, Rust


REST, Agile, On-page SEO, Object-oriented Programming (OOP), Design Patterns, Search Engine Optimization (SEO)


Docker, Linux, WordPress, 1C Bitrix, Amazon Web Services (AWS), Shopify, Drupal, Firebase


PostgreSQL, MySQL, Redis


English, Computer Science, Single-page Applications (SPA), APIs, Front-end, User Interface (UI), SEO Tools, Full-stack, Scraping, Apollo, CRM APIs, Integration, eCommerce, Technical SEO, Website Audits, Architecture, Web Development, API Integration, Front-end Architecture, A11Y, Streaming, Algorithms, OAuth, Back-end, Fintech, Technical Leadership, Cross-functional Team Leadership, Amplitude, TypeORM, Mathematics, Physics, Team Leadership, Page Speed Optimization, ChatGPT API

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