Senior Frontend Developer, 12+ years. I build complex, high-performance web interfaces — from large single-page apps to 3D visualization on Three.js / WebGL. Deep TypeScript; comfortable dropping down to native browser APIs and WebGL when performance really matters. I'm equally comfortable with Node.js on the server side — REST APIs, session management, auth, server-side rendering, integrating external APIs and databases.
I've worked at both ends of the spectrum — small teams where a couple of engineers own the entire frontend, and corporations with hundreds of frontend developers — and I know how things get done in both. I prefer environments where one person can still ship a one-line fix without a committee, but I do understand why coding standards, shared practices, code review, security requirements and testing matter.
These days an ever-growing share of my code is written by LLMs — better to go through the technical interviews now, while I still remember how to write it myself.
- Designed a reusable React + nanostores architecture that lets us spin up new internal services (data tables with filters and forms) quickly and consistently.
- Built an interactive timeline as a standalone npm library that renders up to ~30k events on a single screen at 60fps with smooth zooming; reused across several services.
- For the last 2 years, building a tool to visualize and annotate 3D lidar point clouds using Three.js / WebGL — the core data-labeling workflow for self-driving.
- Stack: TypeScript, React, nanostores, Three.js / WebGL, Vite, Playwright.
- Owned the internal tooling that fleet & ops teams used daily — hardware configuration for cars and delivery robots, status / maintenance / planning dashboards, and rides-data visualization with event timelines.
- Single-page app in TypeScript & React, with native browser APIs in performance-sensitive parts, react-query, react-hook-form, Monaco editor and Jest.
- One of two developers who built the seller marketplace frontend from scratch — designed the SPA architecture that stayed easy to extend as the product and team grew.
- React / Redux stack; also contributed pull requests to the Node.js part maintained by a separate team.
- Built complex interfaces for the sellers' service — notably a delivery-setup UI computing time and cost by carrier, location, category, weight and price.
- Built an embeddable widget that had to run reliably inside third-party sites we didn't control — isolated styles and scope, resilient to any host page. React/Redux, Express, Jest, Selenium.
- Conducted 50+ technical interviews for Yandex and mentored junior developers.
Full-stack side project: a Telegram bot with a mini app for calorie tracking — you send a photo or a short description of your meal, the bot works out the calories via an LLM and keeps your daily count. Currently ~170 monthly active users. Designed, built and operated end to end. GitHub access on request; the core architecture is open-sourced at github.com/loysagienn/service-template.
A web app that helps parents track their baby's sleep — logging naps and nights, and making day-to-day sleep patterns visible on an interactive timeline and charts.
An Ubuntu VPS running autonomous coding agents (Claude Code and Codex) wired up with MCP tools, talking to me through a Telegram bot. I'm gradually turning it into my personal assistant: it can already send me an evening digest of important emails, check me in for a flight, or remind me about my mom's birthday — and I keep adding new capabilities.
Competed in several Telegram JavaScript coding contests focused on high-performance vanilla-JS rendering — won $1,000 in one of them.