Mathias Kools

Software Engineer

Hi, my name is Mathias Kools. I am a Belgian🇧🇪 American🇺🇸 from Boston.

Resume

If I didn’t have to squish my resume onto a single page, this is what it’d look like.

Education

I graduated from Reading Memorial High School 🚀 (2014 - 2018).
- I recieved Valedictorian, Presidential Gold Award, and Patrick A. Schettini Award honors⁰.
I graduated summa cum laude with a combined Computer Science and Mathematics degree at Northeastern (2018-2022).
- I finished Software Development, Artificial Intelligence¹, Computer Systems, Object Oriented Design and Algorithms.
- Additionally, I studied Dynamic Models, Combinatorics, Complex Variables, and Statistics and Stochastic Processes.

(0) I’m also proud to be an alum of First Robotics Competition team 4761. My most significant roles were programmer and business president (fundraising).

(1) Don’t get your hopes up. This was a few years before ChatGPT. So we were learning about things like Minimax, and Q-learning: curiosities with limited applicability.

Software Engineering Journey

I’ve been connected to software engineering for over a decade.

In 2012, at 12 years old, I was first introduced to programming through lua. That was how games were scripted in Roblox². I inspected “Free Models” of scripts others created and started experimenting with little tweaks to values and routines.
In 2013 I got into web programming³. I deployed lots of little LAMP stacks on the family desktop and free webhosts like 000webhost. This gave me an early introduction to SQL, PHP, JavaScript (notably with jQuery), and CSS.
In 2014 I learned Python. Python was great for quick scripts to assist with homework.
In 2014 I also learned Java. Java was one of two options to program robots for First Robotics Competition⁴. As a team we used the Command-Based Programming paradigm. To collaborate with the team I also became proficient in Git⁵.
In 2017 and 2018 I turned my web stack experience (but mostly connections 😊) into high school summer internships at CloudHealth technologies.

The company was generous enough to let me take on …
- A cross-team rollout of a Content-Security-Policy header to harden our Ruby on Rails app against XSS-attacks.
- A custom "Sensu" handler to turn alerts into JIRA tickets⁶.
- Maintenance of our systemd configurations, nginx settings and Chef cookbooks.
In 2018 I went to college to study Computer Science full-time. There I learned Racket with my classmates. This was my first introduction to functional-programming and data-driven design.
In 2020 I worked at Liberty Mutual’s Solaria Labs on the Dwellbeing app as my first Northeastern co-op (a work experience semester). On the front-end we used Flutter. In the backend, we used Express (running on NodeJS), and React (with light TypeScript typing) for both API and internal dashboards.

While there …
- I designed a role-based access control system for internal sites to enable and limit access to customer data.
- I got experience working with event-sourced data. Noble, but complicated!
Back at school I took Computer Systems. While the scope was cut due to a global outbreak of COVID19, we still …
- Learned to make small programs in X86 Assembly
- Learned to make small programs in C
- Learned the primitives of basic memory allocators (bucket allocator), filesystems (FUSE), and hashmaps.
In 2021 I took my second co-op at SmartLeaf and gained new experiences in (Oracle) SQL, Redux and Ruby on Rails (again!).
- This was my first experience in a codebase with up to two decades of code decisions. But there were still new things to contribute.
- I designed and implemented HTTP APIs to help large clients automate workflows.
- I chased down some crazy bugs down to HTML input “dirty values”, database caching, and nested database transactions.
- More than anything I learned how to get stuff done. SmartLeaf uses resources judiciously and taught me to make the practical decision (which wasn’t always the perfect decision).
- I’ll never forget my boss told me … just give me a yes or no, stop qualifying the answer.

(2) Back then it was just a shareable game-engine. It was funded by kids paying for cosmetics, and the ability to publish more games. The business model has since become more complex.

(3) Brett McLaughlin’s Book PHP & MySQL: The Missing Manual was the first programming book I ever owned.

(4) Outside of FRC, Java was also my first step outside Roblox for game development. And of course, the java.awt.Robot class was great for pranks.

(5) The book Git Pocket Guide: A Working Introduction has been influential to my git workflow. Commit often, rebase and squash before pushing, and make decision-capturing messages.

(6) Something like this from yelp but with different functionality to cut down on duplicates.

In 2022 I graduated from Northeastern and started work at ChaosSearch on the backend of a distributed search and analytics database.

This gave me experience with Scala, Akka Actors, Akka Streams, and AWS S3.

We debugged this JVM app with tools like JFR (for investigating live events like GC pauses), VisualVM (for looking at heap dumps), and Java Agents (to instrument classloading). We created terraform providers. And we made custom spark data formats.
- I joined a churning “windowed monitoring” project. Here, I helped get implementation⁷ and a complete internal rollout over the line. By connecting ingestion directly to our query engine (skipping index traversal), we could monitor on just the latest data, and provide huge compute savings⁸.
- I headed an effort to modernize our deployment and application APIs with best RESTful practices. This was my part in a larger effort to develop OEM opportunities.
- I headed a significant effort to connect spark to SAAS ingested data to open opportunities in Databricks and Amazon EMR.
  - I implemented a crazy and brilliant idea from one of my colleagues. To break into a rather locked down databricks runtime, we used a java instrumentation agent to modify bytecode as it was loading. We modified databricks libraries to allow us to call into our own library code. I’ve written more about bytecode here.
- I was also happy to contribute to open source projects during this time.
  - Either to help library dependencies stable release milestones.
  - Or to further my own understanding of the tools we used.
- I started a running tradition that’s outlasted even my own interest in distance races. You can read about the first event we did here.
In 2025 I started in the “Software Engineer II” role at Starburst. I joined the “connectors” team which maintained open-source and proprietary Trino connectors.
- This role was highly dynamic. We triaged and fixed bugs and performance issues reported by Starburst’s 200+ customers across 55+ connectors.
- I submitted 13 patches to the Trino open-source repository.
  - I think my favorite change was fixing a CVE report by upgrading a dependency, and working around a bug introduced in secure library versions.
- I spearheaded the design and development of a new “OpenAPI” connector to onboard more customer use-cases into the Starburst universe.
  - As shown in the blog post this could allow customers to load GitHub data without ETL.
  - But as shown in the documentation it works with any OpenAPI description.
  - I’m proud of the out-of-the-box thinking to generate Trino table functions. This had no precedence, and so it was a hard fight to get customers and teammates to trust the pattern.
This role gave me experience with open data formats like Apache Iceberg and Delta Lake. This was also the year LLM coding harnesses really started to be effective, and I could start experimenting with driving development through Claude Code.
In 2026 I decided to move on from Starburst and join the Search Platform Team at CarGurus!

(7) Implementation touched all sorts of interesting technology that ChaosSearch had developed.

A distributed query engine that spread work across hundreds of nodes.
A sophisticated query optimizer to rewrite and pushdown parts of a query.

(8) These savings were so significant that we could turn on old alerts. We wrote new alerts for faults in ingestion. We could even ring phones 15x faster (running every quarter of an hour to every minute!)

Work Experience

Contact

I communicate from mathiaskools at gmail dot com.

External Pages

These are public profiles I maintain.

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