LEMP Stack for WordPress: Nginx, MariaDB 11.8, and PHP 8.4 on Debian 13
Step-by-step LEMP stack setup for WordPress on Hetzner VPS. Nginx tuning, MariaDB 11.8 InnoDB configuration, PHP 8.4 FPM static pools, OPcache JIT, and kernel optimization.
Blazej Mrozinski, PhD
Science gives us clarity, but product work gives it purpose.
Psychologist · Psychometrician · Product Leader · Data Scientist
I'm a psychometrician and product designer with a PhD in social cognition who spent twenty years in the lab studying how people think — then started building products that use that science. Think of me as a human translator between science and product — curious by default, never fully satisfied with easy answers.
What I Can Help With
Problems I solve — as an independent consultant or through my companies
Psychometric Assessment & Matching
Career quizzes, competency batteries, personality instruments, cognitive ability tests — designed with IRT and CTT, validated before deployment. Plus the scoring and matching systems that make results actionable. Used by LSEG, EPAM, and HSE Ireland.
See GyftedGrowth Engineering & SEO
Programmatic SEO at scale (1,200+ pages for Prawomat, 1.2M users for Gyfted), AI/LLM optimization for ChatGPT and Google AI Overviews, and product-led growth systems. Zero paid spend — all organic, all compounding.
See Digital SavagesProduct Consulting
From concept to production — scoping, specification, and product direction for assessment platforms, workforce development systems, AI editorial tools, and legal tech. I lead product, engineering teams handle code.
See my workStatistical Modeling & Research
SEM, multilevel modeling, latent class analysis for complex research. Published in JPSP, Self and Identity, Frontiers in Psychology. Teaching stats and research methods at SWPS University since 2006.
See SWPS"The gap between 'we think this works' and 'we measured that this works' is where most products fail."
15
Peer-Reviewed Papers
4
Ventures Co-Founded
6+
Products Shipped
20+
Years in Academia
Case Studies
How I approach problems — the methodology, the results, and what I learned
"I'm not a developer. I'm a psychologist who builds products. The science disappears into the product — that's the point."
Companies
Things I started, run, or helped build from the ground up
Writing
How I think about measurement, products, and the places they overlap
How I Built a Knowledge Base That Makes AI Actually Useful Across Projects
AI coding assistants work well in a single repo. They fall apart across multiple projects and companies. I built a 30-document knowledge base that gives AI full context in 30 seconds instead of 15 minutes.
WordPress on Hetzner VPS: Why I Left Managed Hosting and Built My Own Server
I moved my WordPress and WooCommerce sites from managed hosting to a Hetzner VPS. Full walkthrough of server provisioning, SSH hardening, and firewall setup on Debian 13.
Let's talk
If any of this maps to a problem you're working on — pick a 30-minute slot. No pitch, no deck. Just a conversation about what you're trying to solve.
Prefer email? Drop a line below — I read everything.