Where I’ve worked

Founding / Full-Stack Engineer

Contera AI — Wrocław, Poland

Led full technical implementation of an AI-powered SaaS platform, working directly with the CEO and owning all architecture, development, and deployment decisions.

• Built the platform end-to-end: Next.js 15 (App Router, Turbopack), React 19, TypeScript, MySQL on DigitalOcean Managed DB with connection pooling.
• Integrated 4 LLM providers (OpenAI, Anthropic Claude, Grok, DeepSeek) with provider fallback logic for AI-powered ad generation - ensuring high availability and cost optimization.
• Designed and deployed a self-hosted MCP (Model Context Protocol) server, integrating it with Claude Desktop to enable agentic control over internal tools, live database queries, and n8n workflow triggers.
• Connected Google Ads API (OAuth, Keyword Planner), Facebook Ads API + Pixel, and Bing Ads for direct campaign publishing and cross-platform performance tracking.
• Built data pipeline: Google Sheets API for reporting, Google Analytics Measurement Protocol, PostHog for product analytics, and Facebook Pixel for conversion tracking.
• Implemented Stripe subscription billing with tiered pricing, webhook reconciliation, and full checkout flow (server + client SDKs).
• Designed workflow orchestration with n8n (HMAC-SHA256 signed webhooks), Brevo email campaigns, and Telegram bot notifications.
• Built web scraping infrastructure: Cloudflare Workers serverless scraper, ScraperAPI, and ScreenshotOne for competitor analysis features.
• Shipped production UI: shadcn/ui + Radix primitives, Framer Motion animations, command palette (cmdk), i18n.
• Deployed on VPS with PM2, custom bash deploy/rollback scripts, and structured logging.

Full-Stack Engineer

AgencyAnalytics — Toronto, Canada

Worked on the marketing website for AgencyAnalytics, a SaaS reporting platform, as part of a distributed team. Built and maintained pages using Next.js 15, React 19, and TypeScript with Contentful as headless CMS.

• Developed multilingual marketing pages (6 languages) using next-i18next with Contentful GraphQL API and Apollo Client, fully typed via GraphQL Codegen
• Integrated Algolia search, Segment + GA4 analytics, GrowthBook A/B testing, and HubSpot marketing automation
• Built component library with CSS Modules, Storybook, and Chromatic for visual regression testing
• Implemented accessibility testing with Pa11y and E2E testing with Jest + Puppeteer
• Deployed via Vercel with GitHub Actions CI/CD, Docker, and Semantic Release for automated versioning

Front End Developer

Corteq — Warsaw, Poland

• Organized MongoDB databases to optimize the storage and organization of product data that easily interact with both the administrative and client interfaces, which reduced the time required to complete a query by 1.2 seconds.
• Developed and implemented comprehensive CRUD functions (create, read, update, delete) that facilitate efficient data manipulation in the database.
• Integrated Stripe to simplify payment processing, ensuring secure and uninterrupted transactions for end users.
• Developed a strong authentication system using Clerk, increasing user privacy and improving access control protocols. As a result, the number of security vulnerabilities decreased by 98%, and user authentication time decreased by 70%.

Front End Developer

IndustrialBank — Kyiv, Ukraine

• Developed a web system with client and admin parts for leasing the bank's real estate.
• Combined databases, which reduced the time required to approve a lease by 13 hours, and increasing the bank's real estate profits by 26%.
• Created a web-based system for a bank subsidiary that improved the company's production and trading system by facilitating the process of ordering goods by large customers (hypermarkets).
• Improved database queries, which reduced the number of queries and reduced the load on the server side.
• Contributed to the development of user-friendly interfaces for IndustrialBank's online banking platform, resulting in an 18% increase in user engagement during the training period.