Why Claude should stay replaceable
How I keep an application independent from Claude and other AI providers using an owned interface, real evaluation cases and a fallback that works.
Ferenc Papp
Senior Full-Stack Developer & AI Solutions Engineer
I build web applications with Laravel, Vue.js and Python/FastAPI, with or without AI built in. 15+ years, clients across Europe and the US.
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Who I Am
I'm a full-stack developer and AI engineer in Debrecen, Hungary, and I've been building for the web for over 15 years. Most of my work is Laravel and Vue.js applications, and more and more of it puts language models inside them: search, classification, assistants.
Since October 2024 most of my time goes to two related companies, DataExpert and its sister company Rubiklab. At DataExpert I build Progressive Web Apps on Laravel and Vue.js, with Python services behind them.
At Rubiklab I work as Senior AI Solutions Engineer on Studio, their in-house product, and on AI research: fine-tuning and benchmarking language models, semantic search over vector databases, sorting text into categories with LLMs, and tuning model settings until the same input gives the same answer.
Services
Custom Web Applications
Laravel and Vue.js applications and Progressive Web Apps, with Python services where they fit. Tested code, and an architecture the next developer can find their way around.
AI Integration & Automation
Language models built into your product: RAG pipelines, semantic search, vector databases, agent workflows, and fine-tuning when an off-the-shelf model isn't enough. Monitored, with costs kept in check.
Technical Consulting
Architecture reviews, AI strategy, technology choices and performance work, as focused engagements next to my current projects.
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Testimonials
Excellent developer and very easy to work with. Great knowledge of PHP frameworks, excellent English and very good communicator, and very reliable.
Reliable and fast. We have been working with him for years. He built several of our websites from scratch. I can only recommend him.
Ferenc is a very talented developer. He quickly got to grips with what was required and delivered everything (and more) that I expected. I would happily work with him again.
Tech Stack
AI & LLM
Backend
Frontend
DevOps & Tools
Mobile & PWA
Experience
2024 – Present
Senior Full-Stack Developer
DataExpert
Designing and building Progressive Web Apps for the company's main projects. Laravel backend, Vue.js frontend, Python scripts and services behind them.
2024 – Present
Senior AI Solutions Engineer
Rubiklab
Generative AI integrations and research, including Studio, the company's in-house product. Fine-tuning and benchmarking language models, semantic search with vector databases, LLM text classification, and tuning model settings (temperature, top-k/top-p) so the output is repeatable.
2017 – Present
Full-Stack Developer & Technical Consultant
Self-employed (Sole Proprietor)
My own practice as a sole proprietor: custom web applications and AI integrations (LLM features, RAG, vector search), plus survey systems for market research clients in the EU and US.
2015 – 2017
Senior PHP Developer
Fathom Minds
Led web app and API development with Yii2. Set up Git infrastructure for the development team.
Earlier roles (2009–2015)
2014 – 2015
Frontend Developer
Oktafone
Startup web application development with AngularJS, JavaScript, HTML5, and CSS3.
2011 – 2014
PHP Developer
Freelancer (pappfer.hu)
Built websites for individuals and companies using PHP, Yii, Laravel, and WordPress. Facebook, LinkedIn, Box.com, and Stripe integrations.
2011
Service Desk Analyst 2nd Line
British Telecom
Configured network devices (routers, switches) for global network support. Communicated with clients worldwide in English.
2010 – 2011
Contact Center Server Administrator
IT Services Hungary
Linux and Windows server administration, Avaya IP phone management. Co-developed a PHP automation tool saving 3+ hours/day — received innovation award.
2009 – 2010
PHP Developer
Concept Solutions
Remote PHP development. Maintained and improved existing codebases, gaining experience with diverse architectures and implementation patterns.
Latest articles
Vite+ 1.0: why I'm starting every new project with it
Vite+ 1.0 is stable and MIT licensed. Why it's my default for new projects, what vp migrate changes in a Laravel app, and when I'd wait.
The AI writes the listing, the code checks it: a WooCommerce case study
A phone app that turns a Facebook post into a WooCommerce event with AI-written SEO, and the six jobs code had to take back from the model.
Frequently Asked Questions
My main work is DataExpert and Rubiklab projects. Next to that I take on a few freelance and consulting engagements: web applications, AI integrations, technical advice. Tell me what you're working on and I'll tell you whether I can help.
Both work: hourly for ongoing or loosely defined work, a fixed price when the scope is clear. What a project costs depends on that scope, so I don't publish a rate. Send me what you need and I'll come back with a quote and an estimate.
It depends on the scope. A small feature takes days, an MVP usually 4 to 8 weeks, a larger platform 2 to 6 months. You get a detailed estimate before we start and regular updates while the work is going.
Through whatever your team already uses: Slack, Teams, email or video calls. You get regular updates without having to ask, and if something slips, I tell you early.
One that still works on the thousandth request. It gives stable answers, logs what it does, stays within a cost limit, and answers from your own data through search instead of guessing.
Yes. I fine-tune and benchmark large language models, design LLM-based multi-class classification systems, and build evaluations that show in numbers which model does a given task better.
Lower temperature and tighter top-k/top-p settings, a fixed output format, answers grounded in retrieved documents, and automated checks on the results. Then the same input gives the same answer.
Laravel, Symfony and Yii2 on the backend; Vue.js and React on the frontend; Python and FastAPI for AI services. For AI: LLM integration and fine-tuning, embeddings, semantic search, vector databases and RAG pipelines.
Yes. I work remotely with teams across the EU and the US, communicating fluently in English and Hungarian across time zones.
Contact
Write to me about your web or AI project.
Next to my work for DataExpert and Rubiklab I take on a few freelance and consulting projects: web applications, AI integrations, technical advice. Tell me what you're building, and I'll tell you honestly whether I'm the right person for it.