Custom AI Agents & Full-Stack Development

SaaS, FinTech, E-commerce, EdTech, AI products, CRM / ERP, Healthcare, Travel, Media, Social, Developer tools, Cybersecurity, Marketplace, Logistics

Available for remote B2B contracts globally

Iryna Vynnychenko

Iryna Vynnychenko

Full Stack AI Engineer | AI automation

I build AI agents, chatbots, AI assistants, LLM integrations and full-stack web applications for businesses. From API integrations and automation to production-ready Next.js products. Discuss your project directly with the developer.

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Highlights8+ years4,200+ Upwork hours100% Job Success100+ launched projects

Hire me for

AI Assistants, AI Agents, LLM Integrations, and AI Architecture first. Websites, web apps, and Mini Apps are available too.

About

Senior Full Stack AI Engineer & Solutions Architect: Custom AI Agents, Telegram Mini Apps, Web Applications & AI Automation.

Video Introduction

Communication style & workflow

💡 Intro video recorded during my Frontend services period — demonstrates my communication style & client-first approach. My current primary stack (Full Stack AI & Automation) is detailed on this site.

Architecting 0 → Production AI solutions and high-performance full-stack web applications. I deliver custom AI agents, LLM integrations (OpenAI, Anthropic, Gemini, DeepSeek), Telegram Mini Apps, and scalable Next.js/React web platforms with 100% personal accountability.

Senior Full Stack AI Engineer & Solutions Architect. High-performance AI products & web platforms in production.

What I Deliver & Engagement Models

  • 8+ years in production: AI Solutions, Full-Stack SaaS, Telegram Mini Apps & Web Platforms (4,200+ Upwork Hours)
  • Senior AI Engineer & Architect: Custom Autonomous AI Agents, RAG Knowledge Bases, Agentic Workflows, LLM Integration & Streaming UI
  • Available for Long-Term Collaboration: Full-Time or Part-Time Contracts (30–40 hrs/week) & Milestone Projects
  • Solo Developer (No Agency): 100% accountability. Direct communication, remote B2B contracts globally, NDA-ready

Stack

ts iconreact iconangular iconsvelte iconnodejs iconflask iconpostgres icontailwind iconredux icongit iconvercel icondocker iconhtml iconfigma iconjest iconcloudflare icon
js iconnextjs iconvue iconthreejs iconpython iconphp icongraphql iconsass iconvite icongithub iconaws iconprisma iconcss iconnpm iconwordpress icon

Projects(100+)

AI Solutions

Examples of solutions available to build, not disclosed client case studies.

AI Agents

Task-oriented agents for workflow automation and tool orchestration.

AI Assistants

Knowledge-aware assistants for customer support and internal teams.

LLM Integrations

Connecting language models to APIs, business data, and existing software.

RAG Knowledge Systems

Document search and grounded answers using retrieval-augmented generation.

  • Multi-tenant product systems on Next.js + PostgreSQL/Prisma - isolated data, built to grow from dozens to thousands of users
  • High-traffic delivery: SSR/SSG/ISR, CDN caching (CloudFront / Vercel Edge / VPS), code splitting, Core Web Vitals under load
  • AWS serverless: S3, CloudFront, Amplify - preview vs production isolation, CI/CD, repeatable deploys
  • API backends at scale (Node.js, REST/GraphQL) with TanStack Query - cache, retries, and optimistic UI for live products

Selected public work

Certificates & Diplomas(9)

Build Your Own AI Coding Agent Harness
Vercel Academy

Build Your Own AI Coding Agent Harness

Building with the Claude API
Claude Academy

Building with the Claude API

Responsive Web Design
SoloLearn

Responsive Web Design

JavaScript
SoloLearn

JavaScript

Next.js SEO Fundamentals
Next.js / Vercel

Next.js SEO Fundamentals

Next.js Pages Router Fundamentals
Next.js / Vercel

Next.js Pages Router Fundamentals

React Foundations for Next.js
Next.js / Vercel

React Foundations for Next.js

Next.js App Router Fundamentals
Next.js / Vercel

Next.js App Router Fundamentals

Responsive Web Design
freeCodeCamp

Responsive Web Design

Client Testimonials

“Iryna turned our Figma design into a live page flawlessly and ahead of schedule.”

Client

Figma to Live Page

Upwork profile

Independent contractor since 2018

Frequently Asked Questions

Answers to common questions about working together

What is your typical project workflow?

For a marketing site we start from the brief or Figma. For product work we start from the domain: business rules, data model, existing APIs. Then architecture, milestones, iterative delivery with daily updates, QA, and deploy. You work with me directly - no middle managers.

Do you work under NDA (Non-Disclosure Agreement)?

Yes, absolutely. I value my clients' security and intellectual property. I am fully ready to sign a standard NDA before we discuss any confidential project details or share source code.

Which technologies do you specialize in?

Core Frontend & Architecture: TypeScript, React, Next.js (App Router, Server Components/Actions), Vue.js, Angular, Svelte, Alpine.js, Webflow, WordPress, Tailwind CSS, GSAP, Lottie, Framer Motion. Backend & Databases: Node.js, Python, Flask, PostgreSQL, Prisma ORM, REST/GraphQL, Docker. AI & Automation: Custom AI Agents, RAG Knowledge Bases, Vercel AI SDK, OpenAI, Claude, Gemini, DeepSeek, Vector DBs, Human-in-the-loop workflows. State & Cloud: TanStack Query, Zustand, AWS, Vercel, CI/CD.

How do we get started?

We can schedule a video call or chat via Upwork/Telegram/WhatsApp to discuss your project scope. Once we align on requirements, I can provide a fixed-price estimate or start on an hourly basis.

Do you work with Ukrainian companies as a registered private entrepreneur?

Yes, absolutely. I am officially registered as a private entrepreneur (Group 3) in Ukraine, meaning we can sign an official contract for web development services, issue invoices, and sign acceptance acts.

How do you drive value (Scope & Leadership)?

Architecture & MVPs, performance optimization, mobile & cross-browser reliability, design systems, full-stack debugging, and AI-augmented backend engineering.

  • Architecture & MVPs: Scoping and launching scalable web products from zero to production.
  • Performance: Auditing legacy code, cutting bundle sizes, and maxing out page speed.
  • Mobile & Cross-Browser Reliability: Responsive, consistent experiences across devices, browsers, and screen sizes.
  • Design Systems: Building reusable, accessible (a11y) UI kits for complex apps.
  • Full-Stack Debugging: Tracking down and fixing production issues across frontend & backend.
  • AI-Augmented Backend & Agentic Workflows: Leveraging Claude Code MAX, Gemini, Codex & Cursor to accelerate secure API, microservice, and database execution with human-in-the-loop validation and TDD.

Why do clients choose you?

8+ Years | 4,200+ Upwork Hours, Team Player, Solo Developer accountability, and Product-Minded execution.

  • 8+ Years | 4,200+ Upwork Hours: Reliable, top-rated expertise.
  • Team Player: A reliable frontend partner for Backend & ML engineers and teams.
  • Solo Developer (No Agency): 100% accountability. Fast syncs, direct communication, NDA-ready.
  • Product-Minded & Business-Driven: Combining strong engineering with a Product Engineer mindset to directly impact product metrics.

What do you build?

Available for end-to-end development or jumping in at any stage:

  • SaaS Products & Web Platforms
  • AI-Powered Applications & AI Tools
  • AI Agents & Autonomous AI Systems
  • AI Chatbots, Conversational AI, AI Assistants & AI Copilots
  • Custom CRMs, Sales Platforms, Admin Dashboards & Back-Office Systems
  • Marketplaces, Multi-Sided Platforms, FinTech & Real Estate Platforms
  • Analytics, Reporting, Data Visualization, Booking & Scheduling Systems
  • Workflow Automation, Internal Business Tools, E-commerce & Subscription Platforms
  • High-Performance SEO Web Applications & MVPs from 0 → Production

Let's work together

SaaS, MVPs, and product UI on React and Next.js. Scope and timeline on a short call.

Need an AI chatbot, assistant, agent, LLM integration or architecture review? Tell me about your project.

i.vynnychenko@gmail.com