RuslanSemenov
Profile
Full-stack engineer with 20+ years of commercial software development — starting with PHP, Delphi, and jQuery before specializing in React/Next.js and Vue.js. Track record of architecting multi-tenant apps, leading teams of 10+ engineers, and shipping from prototype to production.
Experience
Owner & Fullstack Developer
Self-funded SaaS product (CarCRM) — idea to production in 4 weeks. Car Trading Management platform for auto dealers.
- Built a multi-tenant SaaS from scratch: inventory, parts catalog, sales, repairs, finances, messaging, storage management, and per-user notifications (Telegram, email, push)
- Multi-tenant architecture: each dealer company gets an isolated PostgreSQL database resolved from subdomain
- Role-based access — Admin / Manager / Mechanic; public multilingual storefront (English, Ukrainian, Polish)
Stack: Next.js 16, TypeScript 6, tRPC v11, Auth.js v5, Prisma 7, ShadCN + Tailwind v4, TanStack Query/Table, Docker, Hetzner VPS
Frontend Engineer → Lead → Staff Frontend
AI-powered event management platform for trade shows, exhibitions, and conferences — used by organizers worldwide for registration, networking, and community engagement.
- Drove frontend technical strategy across products; designed scalable solutions for multi-tenant apps and domain-based server configuration
- Led architectural decisions for Next.js 14 (App Router, RSC); migrated E2E testing from Cypress to Playwright — parallelized test runs and reused authenticated session state instead of logging in per test, cutting suite runtime by 50%+
- Collaborated with backend, mobile (iOS/Android), and product teams on system-wide decisions; acted as technical mentor across teams
- Led the frontend team across multiple products; ensured delivery quality and architectural consistency
- Designed React + Next.js architecture: SSR/CSR strategies, i18n, custom auth providers, token-based auth in multi-domain environments
- Built an interactive 3D virtual exhibition booth in Three.js (see: obox.vialan.com.ua)
- Owned performance optimization, memory leak debugging, and application stability; grew the frontend team from 2 to 10 engineers across 3 teams, mentoring developers and defining best practices
- Migrated admin panel to React.js; introduced hooks, modular architecture, and shared UI layers
- Developed and maintained an admin panel on Vue.js: complex forms, role-based access control, reusable UI components
- Built Online Rooms from scratch: real-time video/audio/chat on Vue 2, WebSockets + Amazon Chime SDK. Shipped during COVID, directly helped retain clients. Still an active part of the platform.
- Used Mapbox for geospatial exhibitor mapping; later replaced with a custom floorplan renderer built on Three.js
Stack: JavaScript · TypeScript · React · Next.js (App Router, SSR, RSC) · Vue.js · Auth.js · Jest · Vitest · Playwright · AWS SDK
Owner & Fullstack Developer
- Started coding in Basic and Pascal as a child; self-taught PHP, jQuery, and Delphi — building web and desktop applications since the late 1990s
- Built web applications for clients and own business operations (Vue.js, Nuxt, jQuery, Laravel, PHP)
- Managed a network of 4 computer clubs with 100+ staff across café, parking, leasing, and software operations
- Platform: vialan.com.ua — online since 2005 (verifiable: archive.org history)
Deputy General Director
- Accounting, financial reporting, and high-level operational management of the enterprise
Employment Specialist
- Employment of former miners; bilingual documentation; represented the project to local enterprises