About me
In short

I’m a software engineer, a husband and a father of four. I currently work at Mireo on a distributed spatiotemporal database called SpaceTime.

My interests are in systems programming, database engines, distributed systems, network protocols, programming languages & tools (a non-exaustive list).

I like solving problems by writing code, seeking the simplest and most elegant way to do it.

I don’t particularly like searching for bugs, so I try very hard to avoid making them in the first place, by repeatedly simplifying things, avoiding mutations and shared state, making things correct by construction, and by keeping code local, readable and obvious.

I like to build systems from robust foundations all the way to the top by composing well-defined and reusable components. When doing so, I hope to be less dumb next year than now, so I try to make systems easy to change, improve and extend as I learn more about the domain and the environment it lives in.

I like to make tools for myself and others to automate processes, speed up day-to-day work, make simple things easy and hard things possible.

Besides programming, I like to teach and explain things to others. I also really like to read books, write, cook, walk outdoors, and do things with my hands.

Work

Lead Software Engineer, Mireo d.d.

SpaceTime | Full-time | Zagreb, Croatia
Jul 2023 — Present
  • Led small project teams (2-4 people) working on the query engine and on data-science applications: did feature design and prioritization, mentoring, reviewing, coordinating.
  • Maintained the existing database engine and led the effort to implement a successor one: parser, planner, physical/logical typesystem etc.
  • Designed and implemented database driver libraries in Rust, C/C++ and Python: async, robust, zero-copy, streaming.

Senior Software Engineer, Mireo d.d.

SpaceTime | Full-time | Zagreb, Croatia
Jul 2021 — Jul 2023
  • Senior maintainer of the database engine: implemented spatial joins, temporal & range types and functions, introduced the database catalog and users/roles/ACL model etc.
  • Worked on a side project of battery range prediction modelling: implemented the data processing pipeline, initial model training and periodic retraining in streaming mode.
  • Mentored other colleagues, interviewed job candidates, did customer relations.

Software Engineer, Mireo d.d.

SpaceTime | Full-time | Zagreb, Croatia
Jul 2018 — Jul 2021
  • Implemented large parts of the MSQL query engine from scratch: Apache Calcite-based planner + custom opts and physical placement + LLVM IR codegen + JIT compilation
  • Implemented full set of builtin functions & relational operations: aggregations, joins…
  • Wrote full documentation of the query engine and it’s features, covered it all with tests.
  • Side project: implemented streaming of events from internal Apache Kafka data processing pipeline to the EmberJS web app through the C# backend using WebSockets.

Software Engineering Intern, Mireo d.d.

Navigation | Part-time | Zagreb, Croatia
Sep 2017 — Jul 2018
  • Developed a CRM web app for licencing, device management, reporting and software updating (EmberJS + C# + MySQL stored procedures)
  • Simplified saved places management in the navigation app, implemented remote syncing across devices via cloud storage.
Education

M.Sc. in Computer Engineering

FER, University of Zagreb | GPA: 4.96/5.00
Oct 2016 — Jul 2018
Graduated summa cum laude, Bronze Plaque “Josip Lončar” for academic achievements

B.Sc. in Computer Engineering

FER, University of Zagreb | GPA: 5.00/5.00
Oct 2013 — Jul 2016
“Josip Lončar” awards for academic results (years: 2014, 2015, 2016)
Achievements

Central European Regional Contest (CERC)

2015
University competitive programming contest: 9th place out of 61 teams.

International Chemistry Olympiad (IChO)

2012 — 2013
Silver and bronze medals on olympiads in Washington and Moscow.

National academic competitions

2008 — 2013
Chemistry: 3× 1st, 1× 2nd place; History: 1st and 2nd places; Programming: 2nd place; Physics: 2nd award
Skills

Programming languages

C++, Rust, Python, SQL, C, Java, HTML/CSS, JavaScript, C#, Go, Haskell

Databases and services

Postgres, SQLite, Nginx, MySQL, Kafka, Scylla, ZooKeeper, DRBD

DevOps and sysadmin tools

Linux, Git, Bash, Docker, Ansible, PyInfra, Nix, Jenkins, AWS

Soft skills

Leadership, Mentoring, Technical writing…

Languages

Croatian, English (fluent), German (basic)
Personal

I’m a Catholic, a lover of history, philosophy and literature.

I subscribe to the Thomistic school of philosophy, and consider it the best intellectual system for understanding the world around us, and also the only one that really gives sufficient justification to the idea that we can understand anything at all.

The most influential authors and thinkers on me thus far were:

  • G. K. Chesterton, J. R. R. Tolkien, C. S. Lewis, Joseph Ratzinger (among those from the past)
  • Edward Feser and Anthony Esolen (among the living ones)

The books I’d recommend everyone to read are:

  • Orthodoxy and The Everlasting Man by GKC, bringing back wonder into our artificially dulled world,
  • The Lord of the Rings by JRRT
Contact
location
Zagreb, Croatia
email
zvonimir at jurelinac com
github
github.com/zjurelinac
linkedin
linkedin.com/in/zjurelinac
contact
contact form link
resume
download as PDF