Difficult problems don't need difficult solutions.
I'm Zoltan Benko, a full-stack and solutions engineer in Cluj-Napoca. Fourteen years of turning complicated requirements into systems that stay simple enough to run.
Five years inside Klarna's integration systems.
- Integrations
- Klarna's integration and reverse-integration systems, including the services and flows that connect Klarna to partners such as Google.
- Session lifecycle
- Initiation and lifecycle flows spanning backend APIs, frontend applications and external systems — including what happens when a session expires halfway through.
- In-store payments
- QR and payment integration flows for physical retail.
- Money movement
- Reconciliation, remittance and event-processing systems.
- Infrastructure
- RDS IAM database authentication, CloudFront, and security-related infrastructure changes.
- Operability
- Application metrics and notifications, so a failure is visible to us before it is visible to a customer.
- Compatibility
- Modernising systems one piece at a time, keeping older clients working instead of betting the product on a rewrite.
The recurring part of the job is finding the simplest architecture that solves the actual problem, and still lets the system change afterwards.
The route here wasn't a straight line.
VoiceMailTel
Web designer and developer
Where the career starts. VoIP systems and client applications for an international roster, mostly Canadian, built on Angular 1, CodeIgniter and WordPress.
B2B Media
Web developer
Commercial projects for international clients, across WordPress, React and Angular.
BitStone
Web developer
A year of WordPress work, built on Thrive Themes.
ruby tribe
Web developer
Health applications for international clients — SkinVision among them — mostly React front ends on Ruby on Rails.
Yopeso
Frontend developer
Hired for the frontend, and there when the whole stack became JavaScript and TypeScript — Node.js on the server, increasingly Next.js on the front. Kept following problems past the frontend's edges.
Klarna
Senior / lead full-stack engineer
End-to-end ownership across the stack — mostly Next.js and infrastructure — and the five years of integration work above.
Two systems nobody asked me to build.
xplatform.dev
An opinionated platform for building production web applications, sitting between a website builder and custom software. Rather than asking an AI to invent an application from nothing every time, it hands the AI tested architectural pieces to compose and configure.
Built with Next.js, React, TypeScript and Node.js, on PostgreSQL with Drizzle and Better Auth.
xfiles.dev
File management as an API. Uploads go straight to object storage through presigned URLs and never touch the application server; everything is served back over a CDN, with resized image variants generated on first request and cached at the edge.
Every image on this site goes through it — the covers on the articles below were uploaded, resized and delivered by XFiles.
They are the clearest version of how I build: hide the complexity from the person using it, keep the architecture underneath explicit.
I enjoy difficult engineering problems. I just don't believe they need difficult solutions.
Understand the system. Find the constraint that is actually binding. Remove what isn't carrying weight. Then build the smallest architecture that can reliably hold the product — one other engineers can read, operate and extend, rather than one that is impressive only because it is complicated.
The work I find most interesting sits where product thinking, software architecture, developer experience, AI and distributed systems overlap.
What I work with
Engineering
- Solution engineering
- Software architecture
- System design
- API and integration design
- Frontend architecture
- Backend development
- Production reliability
Technologies
- TypeScript and JavaScript
- React and Next.js
- Node.js
- PostgreSQL and SQL
- REST APIs
- AWS, CloudFront, RDS
- HTML, CSS, Git
Delivery
- Technical ownership
- Architecture decisions
- End-to-end project delivery
- Cross-team collaboration
- Production troubleshooting
- Code review
- Incremental modernisation
I write things down.
Articles and notes, mostly working through problems in public.
Elevating UX with Design Systems in 2026
Explore how design systems and component libraries enhance consistency, reusability, and efficiency in today's UX landscape.
Mastering Technical Strategy: Decision-Making in 2025
Explore effective strategies for technical decision-making, balancing trade-offs, prioritizing projects, and building impactful roadmaps in today's dynamic tech landscape.
Mastering Technical Strategy and Decision-Making in 2025
Explore effective strategies for technical decision-making, prioritization, and roadmap development to navigate today's complex software landscape.
Ask my AI anything about my work.
If you have a system worth simplifying, I'd like to hear about it.
Based in
Cluj-Napoca, Romania
Languages
- Hungarian — Native
- Romanian — Fluent
- English — Professional working
Education
Self-taught engineer. Secondary education, travel guide specialisation — studied software independently from a young age and never stopped.