Product design for startups
You build fast.
Your design should keep up.
I'm a product designer with a developer background — I ship designs that are ready to build, prototype in code, and don't need a meeting to explain.
Free 30-min intro call
Trusted by TwentyThree · InStream · URSTYLE
Mateusz is one of those designers who can take over "I have this idea... play with it and see if there's something?" — and also a top of the class UI designer who executes the final pixels with the last detail considered and systemises it.
Sarper Erel — Building Last.app, prev. TwentyThree
Projects
What can I help you with?
Product design
Intuitive interfaces for complex products — proven across CRM, video platforms, and e-commerce. Designs your devs can build without a meeting.
Design systems
Scalable component libraries that keep your product consistent and speed up development. The one I built at TwentyThree still powers every new feature.
Websites & prototypes
High-converting websites and working prototypes — designed and built. HTML/JS background plus an AI-powered workflow means you see it running, not just mocked up.
Hi, I'm Mateusz 👋
I'm a product designer with a developer background, helping founders shape and ship digital products — from early concepts to production-ready interfaces.
I've worked with SaaS companies like TwentyThree and InStream CRM, leading design on new features, redesigns, and full system overhauls. I've been TwentyThree's design partner since 2018 — currently as their only product designer.
I wholeheartedly recommend Mateusz to everyone who is looking for skilled UX and Product Design specialist!
Ready to level up your product?
Tell me what you're working on — I'll come back with a clear plan and actionable next steps. No fluff, no sales pitch.
Book a call →Not ready for a call? Write me: mateusz [at] mmeller.com