10/12/2026 updated
100 % available
Team Lead & Full-Stack Engineer | LLM Systems | TypeScript, React, Node.js
Wroclaw, Poland
Only remote
MSc Biology, Zaporizhzhia National UniversityAbout me
Team lead and full-stack engineer, freelancer since 2014. I lead the engineering team of a UK online pharmacy, a regulated healthcare platform. I build in TypeScript, React, Next.js, Node.js, PHP and Python, and I own LLM systems in production. Fully remote from Poland, B2B invoices.
AI AgentsTailwind CSSOpenAIVertex AIPHPArtificial IntelligencePython (Programming Language)PostgreSQLMongoDBNode.jsRedisNext.jsSystems IntegrationTechnical ManagementTypeScript
Full-Stack Development
Expertise across the full stack using TypeScript, JavaScript, PHP, and Python. Frontend development with React, Next.js, Vite, TanStack Query, Zod, and Tailwind CSS. Backend development with Node.js, Bun, Express, Temporal, BullMQ, REST, and GraphQL.
LLM Systems & AI Integration
Ownership of Large Language Model systems in production, including Retrieval-Augmented Generation (RAG), prompt caching, batch inference, model fallback chains, and multi-agent runtimes using Anthropic Claude, OpenAI, and Google Vertex AI. Experience building Model Context Protocol (MCP) servers and LLM audit pipelines.
Engineering Team Leadership
Leadership of engineering teams as team lead and line manager, covering one-to-ones, performance reviews, hiring, onboarding, and setting technical direction. Ownership of projects from scoping to release in regulated healthcare environments.
Database & Data Engineering
Proficiency with PostgreSQL, MongoDB, MySQL, Redis, BigQuery, and pgvector. Experience building data pipelines, analytics reporting, and data correction scripts for production environments.
Cloud Infrastructure & DevOps
Deployment and operations on Google Cloud Platform, AWS, and Vercel using Docker, Ansible, and GitHub Actions CI/CD. Monitoring with Grafana, OpenTelemetry, and Sentry. Feature flag management with Unleash.
Regulated Healthcare Software
Development of clinical decision software registered as a Class I medical device. Experience with GDPR special-category data, clinical rules engines, and blind-agreement release gates for medical rulesets.
Payments & Fintech Integration
Integration of payment and financial services including Stripe, Ryft, and Plaid. Experience building credit risk scoring models and round-up donation services.
Testing & Quality Assurance
End-to-end testing with Playwright and unit testing with Vitest and Jest. Introduction of CI gates and test coverage to codebases that previously had none.
Third-Party Service Integration
Integration of identity verification (Yoti), authentication (Clerk), CRM (Zoho), email (SendGrid), shipping (Royal Mail), and product analytics (PostHog, Google Analytics).
Smart Contracts & Web3
Writing and releasing smart contracts for client projects in environments where deployed code cannot be patched post-release.
Expertise across the full stack using TypeScript, JavaScript, PHP, and Python. Frontend development with React, Next.js, Vite, TanStack Query, Zod, and Tailwind CSS. Backend development with Node.js, Bun, Express, Temporal, BullMQ, REST, and GraphQL.
LLM Systems & AI Integration
Ownership of Large Language Model systems in production, including Retrieval-Augmented Generation (RAG), prompt caching, batch inference, model fallback chains, and multi-agent runtimes using Anthropic Claude, OpenAI, and Google Vertex AI. Experience building Model Context Protocol (MCP) servers and LLM audit pipelines.
Engineering Team Leadership
Leadership of engineering teams as team lead and line manager, covering one-to-ones, performance reviews, hiring, onboarding, and setting technical direction. Ownership of projects from scoping to release in regulated healthcare environments.
Database & Data Engineering
Proficiency with PostgreSQL, MongoDB, MySQL, Redis, BigQuery, and pgvector. Experience building data pipelines, analytics reporting, and data correction scripts for production environments.
Cloud Infrastructure & DevOps
Deployment and operations on Google Cloud Platform, AWS, and Vercel using Docker, Ansible, and GitHub Actions CI/CD. Monitoring with Grafana, OpenTelemetry, and Sentry. Feature flag management with Unleash.
Regulated Healthcare Software
Development of clinical decision software registered as a Class I medical device. Experience with GDPR special-category data, clinical rules engines, and blind-agreement release gates for medical rulesets.
Payments & Fintech Integration
Integration of payment and financial services including Stripe, Ryft, and Plaid. Experience building credit risk scoring models and round-up donation services.
Testing & Quality Assurance
End-to-end testing with Playwright and unit testing with Vitest and Jest. Introduction of CI gates and test coverage to codebases that previously had none.
Third-Party Service Integration
Integration of identity verification (Yoti), authentication (Clerk), CRM (Zoho), email (SendGrid), shipping (Royal Mail), and product analytics (PostHog, Google Analytics).
Smart Contracts & Web3
Writing and releasing smart contracts for client projects in environments where deployed code cannot be patched post-release.
Experience
Professional experience10+ years
Freelancer since2014
Languages
GermanBasic knowledgeEnglishFluentPolishFluentRussianNative speakerUkrainianNative speaker
Project history
Own products and contract work in LLM integration and workflow automation, in addition to the main role. Built an LLM audit pipeline for German medical invoicing in TypeScript with a rules layer that validates model output against the official fee schedule. Maintained GDPR compliance with replaceable EU LLM providers and pseudonymised patient data. Built a multi-agent runtime on Temporal with Claude Agent SDK, PostgreSQL with pgvector, and a Next.js operations dashboard. Reduced LLM calls by approximately half using a Python classification pipeline with a local embedding model.
Leading the engineering team of a UK online pharmacy and regulated healthcare platform. Responsibilities include one-to-ones, performance reviews, hiring, onboarding, and setting technical direction. Ownership of the clinical rules engine (Node.js, React, MongoDB), patient-facing AI assistant with RAG, LLM cost and reliability layer, production MCP server, PHP REST API on WordPress and MySQL, TypeScript backend on Bun with Temporal workflows, prescriber and support apps in React, white-label patient app in Next.js, and partner integration npm packages. Integrated third-party services and introduced unit tests, CI gates, and deployment pipelines on Google Cloud Platform and Vercel.
Full-time freelance work for international clients with 29 client engagements and a 100% Job Success Score on Upwork. Built a credit service for small business founders using Plaid and a custom credit risk scoring model. Built a round-up donation service. Wrote and released smart contracts for client projects. Delivered e-commerce, affiliate, and analytics projects from scoping to production support.