Hey, I'm Julian. I'm a computer scientist and full-stack engineer. I work on Datawrapper, the charting tool behind graphics in The New York Times, The Guardian and many other newsrooms.
When I was a kid, I loved building with LEGO. As a teenager I learned about HTML and CSS, and realized that—when not limited by the availability of bricks—I could build anything I wanted in the browser.
And a second realization followed soon after: On the computer, you can build things that don't just look nice, but actually work. So I learned about JavaScript, PHP and SQL. At that point it was clear to me: I'm going to study computer science—and a couple of years later, I did.
Computer science, it turned out, is very different from building with LEGO and crafting web apps. It involves a lot of theory, concepts, logic and math. You are often not trying to build anything, but to understand something. Fortunately, I enjoyed that just as much. So I learned about C and Python, Prolog, statistics and machine learning.
Today, what I enjoy most is combining both of these angles. Build something cool, but build it methodically: take theoretical concepts and turn them into practical solutions. I love systems that are intricate and complex on the inside, yet straightforward and intuitive on the outside. I also like digging into data to understand things better.
Outside of work, I'm a tabletop gamer and a movie nerd, and I'm into all kinds of sports: powerlifting, running, mountain biking, hiking, tennis and padel.
Full-Stack Engineer
Datawrapper is the charting tool behind the graphics of many top-tier newsrooms. I'm a full-stack engineer on the App Team, where I own features from database to UI, like real-time collaboration in the chart editor.
Data Engineer (Part-time)
For the Data Science Group at Heidelberg University, I built Python ETL pipelines that processed millions of tweets for research projects like EPINetz, and kept the data in shape across MongoDB, Postgres and Elasticsearch.
Full-Stack Engineer (Part-time)
heiCLOUD is Heidelberg University's own cloud, letting institutes spin up and scale their own computing resources. I worked on the platform and built its billing dashboard with Django and Chart.js.
M.S. in Data and Computer Science
Heidelberg University · Grade 1.0
I focused on data science and machine learning, which is where projects like the Bomberman agent and the pandemic countermeasure learning came from. On the side, I took extra courses in economics and geography, and our team won the InformatiCup.
B.S. in Computer Science
Heidelberg University · Grade 1.7
The foundations of computer science and software development, plus economics courses outside my faculty (an interest that stuck). Alongside my studies, I started working part-time, first at heiCLOUD, then at the Data Science Group.
Turns NetworkX graphs into Datawrapper charts by disguising them as scatterplots: nodes become dots, edges become lines. The why and how are in my blog post on social networks in Datawrapper.
open sourceA research platform for exploring how political discourse unfolds on Twitter (now X). I collected the tweets and built the platform in Python and React.
web appA Svelte + Supabase framework for real-time apps: your database becomes a Svelte store that stays in sync across every client. Updates are optimistic, so the UI doesn't wait for the server. I built it as my entry to SvelteHack.
web appopen sourceA movie recommendation app for those evenings when picking a film takes longer than watching one. Built with Python, Supabase, Svelte and Tailwind.
web appdata analysisGermany's national CS competition for students. The 2022 task: schedule trains so passengers end up with as little total delay as possible (NP-hard, of course). Our team from Heidelberg won first place out of 30 submissions.
machine learningdata analysishackathonWhat's the best way to fight a pandemic? We let neural networks learn countermeasures by playing through simulated outbreaks, using collaborative reinforcement learning in PyTorch. Built for the Advanced Machine Learning lecture at Heidelberg University.
machine learningdata analysisI taught an agent to play Bomberman (and, ideally, not blow itself up) using Double Deep Q-Learning in PyTorch. Built for a student competition at Heidelberg University.
machine learningWhere should you shoot from, and where should you aim?
Only 12 of 142 remakes outscore their original, so why do studios keep making them?
Comparing rating behavior between two movie rating platforms: IMDb and Letterboxd.
Turning scatterplots into network graphs, and building nx2dw to automate it.
Comparing music trends on Spotify over the last ten years.
Athletic records keep improving. But is that sustainable forever?
Sequels are worse than the originals. I have data to prove it.
Using open data from OpenStreetMap to estimate education levels, in Germany and worldwide.
A network of artist collaborations, and whether collaborating actually pays off.
The topics of German parliament debates, found with unsupervised topic modeling.
Cinema
I'm a fan of the usual suspects like Tarantino and Guy Ritchie, with a deeper lean toward the dark wit of Martin McDonagh (In Bruges) and S. Craig Zahler (Bone Tomahawk). While I love the grit, my most-watched film is Miyazaki's Princess Mononoke. I also have a massive soft spot for trash movies.
Economics
I'm into Game Theory and enjoy following financial markets closely. For my own money, I'm a boring Boglehead, opting for index funds mostly.
Games
I played a lot of chess when I was younger and still play a game now and then. These days, though, I prefer more casual board and card games.
Sports
I've been a casual powerlifter for years, but I've recently traded some gym time for the pavement to develop a new running habit. Beyond the weights and the miles, I enjoy hiking, getting out on my mountain bike or catching a match of tennis or padel.
Cuisine
I love eating out just as much as cooking at home. My rule in both is variety: I'd rather try something new than order my usual, and the more different cuisines end up on my plate, the better. Except for goulash, that I can eat always.
Music
The best album ever is either Meteora or Hybrid Theory by Linkin Park or Get Rich or Die Tryin’ by 50 Cent.
Let's talk.
hello@jfreyberg.dev