About me

Hello! I'm Alex Harri. I spend my evenings writing about software, mathematics, and design.

I've been writing software professionally for 8 years. Right now I'm working full-time at Paper building tools for designers. The work is a fun blend of math, geometry, design, and performance — right in my wheelhouse.

I'm a father to a wonderful daughter and I love physical activities of all kinds. At the moment I'm kind of obsessed with padel.

Career

My first role was at Taktikal. I was the first employee and front-end developer at Taktikal, and later led the front-end team as a Tech Lead. I was there for 4 years.

In 2022 I joined GRID. I mostly worked on their JavaScript-based spreadsheet engine. This role was heavy on data structures, algorithms, and performance.

I later worked at Arkio, developing their 3D solid modeler written in C#. I worked on the modeling tools and geometry kernel — lots of computational geometry, math, and low-level performance work there.

After Arkio I joined NeckCare to work with some coworkers from GRID. I learned a lot about software architecture and testing while at NeckCare. While there I developed a face-tracking solution for remote rehabilitation. Building that involved real-time computer vision, signal processing, and kinematics — the works!

Writing

My most popular post so far is "ASCII characters are not pixels: a deep dive into ASCII rendering", published early 2026. I spent half a year writing this post, and I'm very proud of the result.

Another post I'm proud of is "The web’s clipboard, and how it stores data of different types", which I wrote in 2024. It looks at the evolution of the web's clipboard APIs and their limitations.

The first post I wrote (back in 2019) was "The Engineering behind Figma's Vector Networks". It's a lengthy post containing over 200 diagrams and illustrations. This post has created many opportunities for me over the years — opportunities that I otherwise would not have been considered for.

I've written three posts about TypeScript, my favorite one being "Why doesn't TypeScript properly type Object.keys?". That post looks at TypeScript's structural type system through the lens of a common frustration most TypeScript developers have probably encountered.

To view all of my posts, visit /blog.

Projects

Many of my personal projects, including this website, can be found on my GitHub page.

Contact

You can contact me via a message on LinkedIn or by sending me an email (you can find my email address on my GitHub page).