Mateusz Gruzewski

I am a software engineer focused on understanding how complex systems behave in production. For more than a decade, I have been designing and evolving backend systems, with most of my work centered around the Java ecosystem, the JVM, observability, and performance diagnostics.

Background

My professional path combines hands-on engineering in large-scale production environments with research in compilers and parallel computing. I currently work as a Principal Software Engineer and Software Architect, where I design and improve mission-critical systems operating under real production constraints.

Before that, I worked on high-scale systems at Allegro, one of the largest e-commerce platforms in Central Europe. Across these roles, I have focused on runtime behaviour, reliability, latency, memory pressure, and the practical realities of operating JVM-based systems at scale.

What I Do

My work is centered on performance-critical systems, system architecture, and production diagnostics. I am particularly interested in how systems fail, how they degrade over time, and how engineers can move from symptoms to root cause using the right diagnostic mindset.

I also speak at conferences and meetups, where I share practical knowledge about JVM internals, profiling, observability, and software architecture. In addition to speaking, I run workshops and create technical materials for engineers who want to better understand how modern systems behave in production.

Technical Focus

JVM runtime behaviour, profiling, and performance engineering
Observability, production diagnostics, and continuous profiling
System architecture and long-lived backend platforms
Distributed systems reliability and operability
Compilers, parallel programming, and performance portability

Research

Alongside industry work, I completed a PhD in Computer Science focused on compiler and runtime systems. My research explored polyhedral model-based compilation and techniques for generating efficient and portable parallel code for multicore CPUs and GPUs.

This combination of industry and research gives me a perspective that connects low-level execution models with real-world software engineering problems.

Speaking & Community

I regularly speak at software conferences and developer communities about JVM profiling, JIT internals, observability, runtime performance, and system architecture. I am also the founder and organizer of Szczecin Java User Group, where I help build a local community around Java and modern backend engineering.

Beyond Work