Kamil OwczarekI build high-traffic platforms and make them fast.
Senior Full-Stack Engineer specializing in multi-market e-commerce, performance optimization, and scalable architecture. Proven track record shipping high-traffic platforms across international markets.
I optimize at every layer.
Database queries, API payloads, frontend bundles, caching strategies. On a multi-market e-commerce platform serving 13 languages, that is where the speed comes from.
- TypeScript
- Vue
- Nuxt
- React
- Next.js
- PostgreSQL
- Prisma
- Vercel
- TypeScript
- React
- Next.js
- Vue
- Nuxt
- Node.js
- PostgreSQL
- Redis
- Prisma
- Tailwind CSS
- Turborepo
- Vercel
Measured in production.
Not benchmarks on a laptop. Each of these numbers comes from a system serving real users.
From schema to pixel.
I ship end-to-end and I build for real users: monitoring, error handling, graceful degradation, zero-downtime deployments.
- 01
Performance Engineering
I optimize at every layer. Database queries, API payloads, frontend bundles, caching strategies.
- 02
Scalable Architecture
I design systems that handle growth. Multi-market platforms, internationalization, microservices.
- 03
Full-Stack Delivery
I ship end-to-end. From database schema to pixel-perfect UI. TypeScript, React, Vue, Node.js, PostgreSQL.
- 04
Production Mindset
I build for real users. Monitoring, error handling, graceful degradation, zero-downtime deployments.
Shipped and running.
Production systems serving real users - from multi-market e-commerce to open-source developer tools.
Deante
A collaborative project developed with Deante, a leading Polish manufacturer of kitchen and bathroom fittings.
Notes from production.
Deep-dives into performance, architecture, and real production challenges.
How We Shaved 22KB Off Our Entry Bundle by Lazy-Loading a Toast Library
vue3-toastify was shipping in the entry chunk of every single page — including those that never show a toast. A dynamic import composable moved it to a separate chunk that loads on first trigger, cutting 22KB from entry.js and 9KB from entry.css.
We Removed One Line of Code and Our SSR Got 3x Faster
How a single inline await in our Vue composable was silently serializing all data fetching during server-side rendering, and how onServerPrefetch fixed it with zero architectural changes.
3,842 Lines of Redirect Constants Were Hiding in Our Client Bundle
How we discovered that three redirect constant files were shipping 316KB of dead weight to every browser, and why moving them to server middleware with a database fallback cut our JavaScript bundle by a third.
The sizes Attribute Is the Most Impactful Image Optimization You Are Not Using
We discovered that our image optimization pipeline was generating perfect srcset values that the browser completely ignored. The fix was a single HTML attribute we had been treating as optional for years.
Stop Using Router.replace() for URL Canonicalization — Use History.replaceState() Instead
We were burning full Vue Router navigation cycles just to fix slug URLs on product pages. Replacing router.replace() with history.replaceState() eliminated wasted re-renders, fixed broken SEO meta tags, and cut client-side canonicalization to a single DOM-free call.
We Replaced Redis With PostgreSQL for Caching — Here's What Happened
Our Redis cache kept dropping TLS connections, taking down the entire caching layer. After a misleading benchmark nearly sent us in the wrong direction, we migrated to PostgreSQL — same performance, zero drops, one less service to manage.
Available for opportunitiesLet's build something together
I'm open to full-time roles, contract work, and interesting collaborations. Let's talk about what I can bring to your team.
- Senior/Staff Full-Stack EngineerRole
- Performance EngineerRole
- Technical LeadRole
- Open to full-time, contract, and consultingTerms