Sviatoslav B.

I create and improve SaaS applications, business websites, and AI features using React, Next.js, TypeScript, Node.js and Cloudflare. I'm a senior frontend architect and full-stack engineer with 13+ years of experience delivering production web applications. Whether you're launching a product or improving an existing application, I can take ownership of architecture, implementation, deployment, and ongoing maintenance. WHAT I CAN HELP WITH • React and Next.js development: Complete applications, complex interfaces, reusable components, and design systems. • Full-stack development: Node.js and Python backends, APIs, PostgreSQL/SQL, database integrations, and payment flows. • Performance and architecture: Resolving frontend bottlenecks, improving maintainability, and modernizing existing codebases. • WordPress development: Creating and customizing business websites, improving frontend functionality, and optimizing performance. • AI integration: AI assistants, retrieval-augmented generation (RAG), multi-step AI agent workflows, streaming responses, and integrations with your application's tools and data. SELECTED WORK AND RESULTS • Piggy and EazeGames: Designed and built frontend platforms from scratch for Piggy, serving 10,000+ business clients, and EazeGames, reporting 4M+ players across 10+ skill games. • Performance optimization: Improved marketing-site performance, reducing page-load measurements from 1.5s to 0.4s and achieving Lighthouse scores of 100 for Performance and SEO. • Application architecture: Designed data-access and state-management layers that enabled a migration from URQL to tRPC without an application-wide rewrite. • English Voice Coach: Created an Android AI application, currently in Google Play closed testing, with local Whisper speech recognition, Gemma grammar feedback, and photo OCR. Works offline. • Llamail: Created an open-source, local-first AI agent with a persona using Python, FastAPI, and ChromaDB, with Gmail ingestion, Telegram integration, and drafts reviewed before sending. CORE TECHNOLOGIES Frontend: React, Next.js, Astro, TypeScript, JavaScript, Tailwind CSS, and Storybook, with attention to accessibility and internationalization. Backend and cloud: Node.js, Python, FastAPI, Django, PostgreSQL, REST, GraphQL, tRPC, Stripe/PayPal/SEPA integrations, and Cloudflare Workers, Durable Objects, D1, R2, KV, and Queues. AI: OpenAI, Gemini, Gemma, Whisper, RAG pipelines, Cloudflare AI stack, tool integrations, and local LLM workflows. HOW WE'LL WORK TOGETHER You'll work directly with me on technical decisions and implementation. Expect clear progress updates, working demos, and early discussions about scope, risks, and trade-offs. Send me your current stack and what you want to implement or improve. My name is Sviatoslav, but feel free to call me Sviat.