Senior full-stack engineer · TypeScript · React · Node.js · Python

Résumé / 2026

Sergey
Eremeev.

The engineer you hand
an unfamiliar codebase and a deadline.

15+ years of production software, from leading engineering teams as Head of Development to shipping a product solo. Hands-on across web, mobile, backend, and cloud, and accountable for it once it is live.

Open to remote roles

Sergey Eremeev
Engineer. Technical lead.
Product-minded builder.
15+
years in production software
1030
engineers on teams I led

Experience across teams at

RedditSocolShare A RefundSensor TowerBeautylishreturnproToptalAgency, Mai?

01 / Selected experience

The work behind
the skill set.

Head of Development, senior full-stack engineer, and founder of My Caddie.

2011 to today. Select an engagement to read more. Employment or long engagementContract via ToptalCurrent
  1. My Caddie2026 — present · Approximate
  2. FullyParsed, Inc.26 Feb — 11 Mar 2023
  3. Share A RefundDec 2022 — Aug 2026
  4. Urban planning platformFeb — Jun 2022
  5. Liist IncNov — Dec 2021
  6. Sensor TowerMar 2021 — Feb 2022
  7. Socol2021 — 2022 · Approximate
  8. Reddit2020 — 2021 · Approximate
  9. Sherpa Digital MediaOct 2019 — Feb 2020
  10. Beautylish2019 · Approximate
  11. Agency, Mai?Mar 2018 — Jun 2019
  12. The Recon GroupAug 2014 — Mar 2018
  13. Independent developmentJul 2011 — Aug 2014

Year-only dates are approximate. Engagements may overlap.

Current Independent product · 2026 — present

My Caddie

Founder & Lead Full-stack Developer

A product built from zero and shipped to production solo.

I own product definition, UX, architecture, security, testing, and cloud delivery. The live foundation covers onboarding, verification, secure sessions, and private dashboards for golf-club operations; booking and tournament workflows come next.

  • TypeScript / AdonisJS
  • Vue 3
  • PostgreSQL
  • Playwright · axe-core
  • Cloud architecture
View details

Context

An independent SaaS product for golf-club operations. I own product definition, UX, architecture, implementation, security, testing, and cloud delivery. It is deployed to production, still in active development, and what gets built next is decided by early usage rather than by a spec.

My work

  • Built the foundation with an AdonisJS/TypeScript API, service-oriented business logic, explicit validators, PostgreSQL/Lucid, and a responsive Vue 3/Vuetify frontend.
  • Implemented registration, email and phone confirmation, password recovery, onboarding, persistent sessions, consent and re-consent, private dashboards, and transactional email/SMS integrations.
  • Designed cloud delivery around an application load balancer, private compute, and managed PostgreSQL in Yandex Cloud.
  • Established a security and quality baseline: rotating Secure HttpOnly sessions, rate limiting, lockouts, consent evidence, structured logging, automated tests, Playwright flows, and axe-core accessibility checks.
  • Run several coding agents in parallel across investigation, implementation, test generation, and review; every change passes type checks, lint, tests, and my own inspection before it ships.

Product status

The current product is a responsive web application in production with early usage. Booking and tournament workflows are designed but not yet shipped.

Technologies & focus

  • TypeScript / AdonisJS
  • Vue 3 / Vuetify
  • PostgreSQL / Lucid
  • Yandex Cloud
  • Authentication
  • Playwright / axe-core
  • Claude Code / Codex
01

Share A Refund

Senior Full-stack Developer

Dec 2022 — Aug 2026

Modernizing a business-critical platform.

Owned delivery in a mature shipping-audit SaaS. Migrated Zend to Laminas and replaced service-locator patterns with explicit dependency injection. Maintained the UPS, FedEx, and DHL integrations and billing-sensitive data pipelines, and helped build Ask SARA, an AI assistant for the platform.

  • PHP / Laminas
  • JavaScript / Vue
  • SQL
  • AWS
  • AI assistant
View details

Context

A mature SaaS platform for parcel shipping audits, refunds, carrier agreement analysis, invoicing, and operational reporting, with a US-based team. My work covered architecture, integrations, data processing, and production reliability.

My work

  • Migrated the Zend backend to Laminas across controllers, services, models, APIs, reports, and background workers.
  • Replaced service-locator and circular-dependency patterns with explicit dependency injection to improve modularity and testability.
  • Built and maintained UPS, FedEx, and DHL integrations: shipment and invoice imports, rate and surcharge calculations, synchronization, duplicate detection, and financial reports.
  • When a defect touched billing or carrier data, traced the root cause, added the test that would have exposed it at the earliest stage, and verified the surrounding workflows rather than stopping at the visible symptom.
  • Helped build Ask SARA, an AI-powered assistant that let users search the platform and understand product data.

Technologies & focus

  • PHP / Laminas
  • JavaScript / Vue
  • MySQL / PostgreSQL
  • Redis
  • Queues & workers
  • AWS
  • AI assistant
02

Socol

Head of Development

2021 — 2022

Led a cross-platform engineering team and wrote production code.

Led the engineers and wrote production code across the platform. Made the architecture decisions, reviewed code, and worked directly with the CEO on technical priorities and risks.

  • TypeScript
  • Node.js
  • React / Next.js
  • React Native
  • AWS · Terraform
View details

Context

A cross-platform product built from scratch: mobile apps, web, backend APIs, and cloud services. I led the engineering team, working on Singapore hours, and contributed directly to the code.

My work

  • Owned the platform APIs, SDKs, and TypeORM-backed data access, with Stripe, Twilio, and OAuth integrations for payments and authentication.
  • Ran technical brainstorms, made the architecture decisions, reviewed code, and kept delivery moving, while writing production code and fixing implementation problems myself.
  • Built across React Native mobile, React/Next.js web on Vercel, and Node.js services on AWS Lambda, S3, and Terraform, with GCP and Firestore where the product needed them.
  • Reported progress, risks, and the business impact of technical problems directly to the CEO, and turned competing ideas into a scoped plan the team could build and operate.
  • Contributed code upstream to StarkWare’s open-source tooling as part of the platform’s integration work.

Technologies & focus

  • TypeScript
  • Node.js
  • React / Next.js
  • React Native
  • TypeORM
  • AWS Lambda / S3
  • Terraform
  • GCP / Firestore
  • Stripe / Twilio / OAuth
03

Reddit

Senior Full-stack Developer · Consumer safety · via Toptal

2020 — 2021

Reusable workflows for a community at very large scale.

Built consumer-safety workflows in React and TypeScript over GraphQL, REST, Python, and Django, and designed a configuration-driven framework that let teams assemble complex workflows from structured JSON.

  • React
  • TypeScript
  • GraphQL
  • Python / Django
View details

Context

Consumer-safety functionality for one of the largest community platforms on the internet, delivered remotely as a contractor through Toptal. React interfaces with a Python/Django backend, at a scale where a broken screen could originate in any layer.

My work

  • Designed a configuration-driven framework that turned structured JSON into reusable React and TypeScript workflows wired directly to API behavior, so other teams could build complex flows without rebuilding the same patterns.
  • Built and debugged consumer-safety workflows across React state, configuration data, GraphQL and REST requests, and the Python/Django backend, using browser DevTools to isolate which layer owned a failure.
  • Worked asynchronously with a US-based team from a time zone most of a day away.

Technologies & focus

  • React
  • TypeScript
  • GraphQL
  • REST
  • Python
  • Django
  • Consumer safety
04

Sensor Tower

Senior Full-stack Developer

Mar 2021 — Feb 2022

Making complex data useful.

Built API aggregation and summary endpoints, turned high-volume market datasets into responsive visualizations in D3, SVG, canvas, and Chart.js, and expanded automated coverage with Cucumber and Cypress.

  • Ruby on Rails
  • Backbone.js
  • D3 · Chart.js
  • Cypress
View details

Context

A data-intensive digital market intelligence platform. I worked across the Ruby on Rails backend and Backbone.js frontend, with an emphasis on useful reporting interfaces and automated validation.

My work

  • Built and extended API aggregation and summary endpoints that supplied structured datasets to reporting and visualization interfaces.
  • Processed high-volume datasets into responsive, dynamically rendered visualizations in D3, SVG, canvas, and Chart.js, using requestAnimationFrame to keep animated updates smooth.
  • Expanded functional coverage with Cucumber scenarios and visual/end-to-end validation with Cypress.

Technologies & focus

  • Ruby on Rails
  • Backbone.js
  • D3
  • SVG / canvas
  • Chart.js
  • Cucumber
  • Cypress
  • Okta
05

Beautylish

Full-stack engineer

2019

Cart, checkout, and gift cards: code where a mistake costs money.

Built cart, checkout, and gift-card flows across a React/Redux frontend and Python services on Flask and Django, with test-driven development in Jest and Cypress.

  • React / Redux
  • Python
  • Flask / Django
  • Jest / Cypress
View details

Context

An online beauty retailer. The work sat on the revenue path, where a wrong total or a broken gift-card redemption costs money the same day.

My work

  • Built and maintained cart, checkout, and gift-card functionality across the React/Redux frontend and Python services using Flask and Django.
  • Worked test-first, using Jest for unit and component tests and Cypress to protect key purchase flows against regressions.

Technologies & focus

  • React / Redux
  • Python
  • Flask / Django
  • Jest
  • Cypress
  • TDD
06

The Recon Group later goTRG, now returnpro

Frontend React Developer

Aug 2014 — Mar 2018

React applications and large-scale commerce.

Developed frontend applications and e-commerce interfaces over a multi-year engagement, including Hulq’s React leasing calculator and the Vipoutlet and DirectLiquidation stores. Worked closely with backend engineers on integrations, checkout, account areas, and responsive user flows.

  • React
  • JavaScript / SCSS
  • WordPress / WooCommerce
  • API integrations
View details

Context

A long-running engagement with The Recon Group, subsequently known as goTRG and now returnpro. I worked in a medium-sized development team on e-commerce, reverse-logistics interfaces, and customer-facing applications.

My work

  • Built React interfaces for Hulq’s multi-step vehicle-leasing calculator, including API integrations, pricing comparisons, and saved calculations.
  • Developed checkout, customer account, and storefront interfaces for Vipoutlet, an online outlet store that helped the business secure a Walmart deal.
  • Contributed to ongoing frontend development on DirectLiquidation and worked across WordPress, WooCommerce, PHP, and SOAP integrations.
  • Translated designs into responsive interfaces, tested across browsers and devices, and coordinated with backend developers to prevent regressions.
  • Built HTML email templates, improved the build workflow with Grunt, Gulp, and Webpack, and took part in the team’s technology decisions.

Technologies & focus

  • React
  • JavaScript / SCSS
  • WordPress / WooCommerce
  • PHP
  • REST / SOAP APIs
  • Grunt / Gulp / Webpack
  • MJML
More experience: shorter engagements and earlier roles

Sherpa Digital Media

Full-stack Developer · Node.js / Vue.js · Oct 2019 — Feb 2020

Client-facing analytics dashboard and user permissions for an enterprise video-streaming platform.

View details

Context

An enterprise video platform bringing live and on-demand streaming into a single system. Its product scope included managing and measuring video used with customers, partners, and employees.

Engagement focus

  • Full-stack engagement focused on a client-facing analytics dashboard and user permissions.
  • Worked with the team across Node.js and Vue.js, bringing input to the dashboard and access-management work.

Technologies & focus

  • Node.js
  • Vue.js
  • Analytics dashboards
  • User permissions

Urban planning platform

Mapbox / Vector Tiles Specialist · Feb — Jun 2022

Specification and implementation of vector-tile editing and rendering for a decision-support platform, with user-defined map styling.

View details

Context

A decision-support platform for urban planning. The engagement centered on how spatial data could be edited, rendered, and styled to support planning workflows.

Engagement focus

  • Supported the team with application specification and implementation for vector-tile editing and rendering.
  • Worked on Mapbox map styling and spatial visualization, including user-defined styling modifications.

Technologies & focus

  • Mapbox
  • Vector tiles
  • Map styling
  • Spatial visualization

Liist Inc

React Developer · Nov — Dec 2021

Mobile web experience for a travel app: saving and organizing places, creating lists, viewing shared lists, Figma implementation with custom UI animations.

View details

Context

A travel app for saving and organizing places. This engagement focused on the mobile web experience accompanying a new version of the product.

Engagement focus

  • The frontend scope covered sign-in, creating lists, adding and organizing places, and viewing lists shared by other users.
  • Translated supplied Figma designs into React interfaces, with custom UI animations and mobile-screen layouts.
  • Worked alongside the backend developer to connect the interface to the provided backend functionality.

Technologies & focus

  • React
  • JavaScript
  • HTML
  • SCSS / CSS
  • UI animations
  • Figma implementation

FullyParsed, Inc.

Senior Backend Developer · Consultant · Feb — Mar 2023

Focused Prisma consulting: backend tasks combined with pair programming and knowledge sharing on relational-data workflows.

View details

Context

A focused backend consulting engagement centered on Prisma. The format combined technical tasks with direct pair programming and knowledge sharing with the client.

Engagement focus

  • Supported backend development work using Prisma and relational-data workflows.
  • Paired with the client to work through Prisma development patterns and explain the nuances of the implementation.

Technologies & focus

  • Prisma
  • Backend development
  • Pair programming
  • Knowledge sharing

Agency, Mai?

Lead Full-stack Developer · Mar 2018 — Jun 2019

Custom WordPress sites, frameworks, and plugins. Worked closely with design on demanding frontend implementations, responsive layouts, and performance optimization.

View details

Context

Custom WordPress projects with substantial frontend and backend development. My work included frameworks and plugins that let clients build and manage their websites.

My work

  • Collaborated with design to find practical implementations for demanding frontend requirements.
  • Built responsive websites and applications, with attention to cross-browser behavior, performance, and animation quality.
  • Set up projects across shared and managed hosting environments, including adapting implementations to managed WordPress constraints.
  • Worked across frontend and backend code, automated build tasks with npm, Webpack, and Gulp, and tested changes for regressions.

Technologies & focus

  • WordPress
  • Custom plugins
  • JavaScript / CSS
  • Responsive UI
  • Webpack / Gulp
  • Performance
Visit Agency, Mai?

Independent development

Freelance Frontend Developer · Jul 2011 — Aug 2014

Started as a freelance frontend developer in 2011, building websites and long-term client relationships before moving into broader product engineering.

View details

Context

Started my career through freelance frontend engagements on oDesk and Elance. Alongside development, I was responsible for managing client relationships and delivery.

My work

  • Built websites against client requirements and developed long-term working relationships through communication and reliable delivery.
  • Managed scope, deadlines, and multiple projects, acting as my own project manager.
  • Continually expanded my frontend skills and portfolio while working independently.

Technologies & focus

  • Frontend development
  • Client communication
  • Project planning
  • Independent delivery

02 / Portfolio

Selected earlier
projects.

Offline-first apps, complex commerce, and visually demanding sites from earlier in my career, kept for the range they show. Recent work is in the experience section above.

Browse nine more archived projects

Vehicle leasing

Hulq

A React leasing calculator that brings vehicle selection, pricing, trade-in details, and financing assumptions into one multi-step workflow.

  • React
  • API integrations
  • SCSS
  • Multi-step workflows
View project

Project context

A car-leasing web application built around a complex pricing calculator. The interface brought together vehicle data, lease terms, and market comparisons to help users explore their options.

My contribution

  • Built a multi-step React interface for selecting a vehicle and calculating lease terms from factors such as vehicle configuration, trade-in, credit score, and annual mileage.
  • Integrated multiple APIs for vehicle information, pricing calculations, and market comparisons.
  • Implemented the ability to save progress at any step, return through a link, and share a calculation.
  • Refined transitions, animations, and frontend performance across the calculator.

Technologies & focus

  • React
  • API integrations
  • SCSS
  • Multi-step workflows
Screen recording from the time of the project.

Digital agency

Mpact Digital

A digital agency website with custom full-page navigation, animated sections, and a card carousel, built with vanilla JavaScript and SCSS.

  • JavaScript
  • HTML / SCSS
  • CSS animations
  • Gulp
View project

Project context

A single-page digital agency website designed around visual storytelling and animated interactions. I built the frontend independently, including its navigation and animation behavior.

My contribution

  • Implemented full-page scrolling and section navigation with vanilla JavaScript, CSS transforms, and transitions.
  • Built a custom card carousel and interactions responding to scrolling, hovering, and clicks.
  • Optimized animation performance for mobile devices and organized the application using an object-oriented approach.

Technologies & focus

  • JavaScript
  • HTML / SCSS
  • CSS animations
  • Gulp
Screen recording from the time of the project.

Branding & naming agency

River and Wolf

A custom WordPress website for a branding and naming agency, with project galleries, page-specific color schemes, and carefully tuned transitions and loading behavior.

  • WordPress / PHP
  • JavaScript / SCSS
  • AJAX
  • Performance
View project

Project context

A website for a branding and naming agency, followed by ongoing development and support. The work combined a distinctive visual presentation with content management that the client could use independently.

My contribution

  • Built a custom gallery system and page-specific color schemes for presenting the agency’s work.
  • Implemented AJAX blog filtering and post loading, lazy-loaded images, a sticky sidebar, and custom post-type management.
  • Refined page transitions and loading animations while optimizing frontend performance.
  • Made content and settings editable in WordPress without requiring the client to write code.

Technologies & focus

  • WordPress / PHP
  • JavaScript / SCSS
  • AJAX
  • Performance
Screen recording from the time of the project.

Retail commerce

Vipoutlet

An online outlet store built with WordPress and WooCommerce, including custom checkout and customer account flows. The project helped secure a deal with Walmart.

  • WordPress / WooCommerce
  • JavaScript / PHP
  • Checkout & accounts
  • SCSS / Grunt
View project

Project context

A large online outlet store developed within the goTRG team. I contributed to ongoing frontend delivery on the WordPress/WooCommerce platform, which helped the business secure a deal with Walmart.

My contribution

  • Implemented new designs and frontend features across the store using JavaScript, jQuery, SCSS, PHP, and WordPress.
  • Built a complex checkout page using object-oriented patterns and developed the customer account area.
  • Worked with backend engineers to catch visual and functional regressions as new features were introduced.
  • Used Foundation and Grunt to support consistent interfaces and a faster development workflow.

Technologies & focus

  • WordPress / WooCommerce
  • JavaScript / PHP
  • Checkout & accounts
  • SCSS / Grunt
Screen recording from the time of the project.

Construction marketing

Carson Corporation

A WordPress marketing website for a construction company, combining large project imagery, video, and custom content blocks with clear information for prospective clients.

  • WordPress / PHP
  • JavaScript / SCSS
  • Video APIs
  • AJAX / History API
View project

Project context

A construction-company website built to present its services and work clearly. The design used large images, varied content sections, and video while keeping navigation and content management straightforward.

My contribution

  • Developed custom WordPress content blocks to present services and project imagery without repetitive page layouts.
  • Integrated video through a video API and adapted the presentation to the site’s design.
  • Built blog filtering and pagination with AJAX and browser-history support.
  • Made the site’s content and settings editable for the client without code changes.

Technologies & focus

  • WordPress / PHP
  • JavaScript / SCSS
  • Video APIs
  • AJAX / History API
Screen recording from the time of the project.

Vehicle auctions

AutoAuctionMall

A used-car auction marketplace built on Meteor.js, connecting buyers with major vehicle auction houses across North America.

  • Meteor.js
  • JavaScript
  • SCSS
  • Foundation
View project

Project context

A large vehicle-auction marketplace for used cars. I worked as part of the team on the frontend of the Meteor.js application.

My contribution

  • Created components and widgets for the auction website, working within the Meteor.js application.
  • Implemented new pages with Foundation and reorganized legacy CSS into a more maintainable structure.
  • Used CSS animations and transitions to refine the interface, while testing and fixing visual and functional issues across existing and new features.

Technologies & focus

  • Meteor.js
  • JavaScript
  • SCSS
  • Foundation
  • UI components
Screen recording from the time of the project.

Wholesale commerce

DirectLiquidation

A complex wholesale e-commerce platform, including merchandise from Walmart, with ongoing frontend development across a large retail catalog.

  • WordPress / WooCommerce
  • PHP
  • JavaScript / jQuery
  • SCSS
View project

Project context

A wholesale marketplace serving business buyers, including products from major retailers such as Walmart. My role focused on continuous frontend development and coordination with the backend team.

My contribution

  • Implemented new designs and features across the WordPress/WooCommerce platform, working with HTML, PHP, JavaScript, jQuery, and SCSS.
  • Checked that backend changes and newly developed features did not introduce visual or functional regressions.
  • Reorganized legacy CSS, implemented new pages using Foundation, and set up Grunt tasks to improve the development workflow.
  • Reviewed the website for bugs and opportunities to improve the design and user experience.

Technologies & focus

  • WordPress / WooCommerce
  • PHP
  • JavaScript / jQuery
  • SCSS
  • Foundation / Grunt
Screen recording from the time of the project.

Design & performance

Educated Body

A visually rich presentation website for the gym and spa sector, with custom galleries, coordinated sliders, and extensive frontend performance work.

  • WordPress / PHP
  • JavaScript / SCSS
  • AJAX / History API
  • Lazy loading
View project

Project context

A design-led WordPress website for a business in the gym and spa sector. The challenge was to retain the richness of the visual design while delivering responsive layouts, smooth interactions, and strong performance.

My contribution

  • Combined lazy loading with carefully coordinated reveal and scroll animations to keep visual interactions smooth.
  • Built custom gallery workflows with AJAX transitions, browser-history support, and sidebars that adapted to different screen sizes.
  • Customized sliders and pagination, including linked sliders for the team area.
  • Adapted complex visual sections for mobile screens and optimized the frontend to keep performance and PageSpeed scores high.
  • Made content and settings editable through WordPress without requiring the client to write code.

Technologies & focus

  • WordPress / PHP
  • JavaScript / SCSS
  • AJAX / History API
  • Lazy loading
  • Performance
Screen recording from the time of the project.

Interactive presentation

Automated Insights

A presentation website for a language-from-data platform, combining video, interactive visual elements, and a custom content system with performance optimization.

  • WordPress / PHP
  • JavaScript / SCSS
  • Video APIs
  • AJAX filtering
View project

Project context

A presentation website for a platform that generates written narratives from data. The site combined video, interactive visual elements, and a custom content system.

My contribution

  • Implemented video-driven and interactive presentation sections, including integration with video APIs.
  • Built AJAX-based content filtering and a custom content system so the client could manage pages without code.
  • Optimized the frontend for performance across the interactive sections.

Technologies & focus

  • WordPress / PHP
  • JavaScript / SCSS
  • Video APIs
  • AJAX filtering
  • Performance
Screen recording from the time of the project.

03 / Technical range

One engineer.
The whole stack.

Depth in TypeScript, React, Node.js, and Python. Enough range to connect the pieces and take responsibility for the result.

Web & mobile

Interfaces that make complex workflows feel simple and stay fast.

  • TypeScript & JavaScript
  • React & Next.js
  • React Native
  • Vue 3
  • SVG, canvas & D3
  • Responsive UI & accessibility
  • Mapbox & spatial visualization

Backend & data

Clear boundaries, dependable integrations, and careful data handling.

  • Node.js · AdonisJS
  • Python · Django · Flask
  • PostgreSQL · MySQL · Redis
  • GraphQL & REST API design
  • Prisma · TypeORM · Lucid
  • PHP / Laminas · Ruby on Rails
  • Queues, background workers & pipelines

Cloud, quality & AI tooling

Architecture and delivery practices that hold up in production.

  • AWS: Lambda, SQS/SNS, S3, CloudFront
  • Terraform & serverless architecture
  • GCP · Yandex Cloud · Vercel
  • Playwright · Cypress · Jest · Cucumber
  • axe-core & accessibility checks
  • Authentication & access control
  • Claude Code & Codex, daily

04 / How I work

Find what matters.
Ship a version.
Improve it.

I’m at my best when the work needs someone who can see the whole system and still care about the details.

For more than 15 years, I’ve worked across product teams, established platforms, and independent projects. Much of that work has been remote: collaborating with teams in the US and leading engineers in Singapore and India. I find my way through unfamiliar codebases quickly, shape the architecture, and follow through on implementation.

I bring technical decisions back to the product: what the team needs, what the user experiences, and what it will take to operate and maintain the result.

AI-assisted development with engineering judgment.

I use Claude Code and Codex to investigate codebases, explore designs, implement bounded changes, and review work. I stay responsible for the result: type checks, lint, automated tests, accessibility tooling, and my own review decide what ships.

Agent proposes a change

01

A bug fix ships with the check that would have caught it.

02

Tradeoffs are explicit: every architecture decision is tied to a product need and the cost of maintaining it.

03

Progress is visible before anyone asks, even when there is nothing to click on yet.

05 / Let’s connect

Your next
engineering
conversation.

Looking for someone who can connect product thinking with hands-on engineering? I work remotely, as a contractor or an employee. Let’s talk about your team.

Work / In detail