Halide and Spectre

Sebastiaan de With and I build Halide as a side project. From the launch announcement:

Smartphone cameras have improved massively over the years, but the shooting experience hasn’t. The built-in camera app is a little too simple, while advanced apps feel like an airplane cockpit. We needed an elegant app for deliberate and thoughtful photography, so we built Halide.

It has very positives reviews on Daring Fireball, iMore, Mashable and more.

It peaked at #3 in the "Top Paid Apps" chart. Download it here.

In 2019 we launched a follow up app, Spectre, which enables handheld long exposures. It was the #1 Top Paid App for one week.


I worked at Twitter from 2009 to 2014. I was the first hire for the newly formed “Mobile Team,” and lead the rewrite of the mobile site. This included ops work like productionizing new services.

In 2010, Twitter acquired Atebits' Tweetie, which became the official client. I became the second iOS developer. For two years I served as tech lead, establishing process, settling architectural decisions, and working with management on the technical side of releases.

In 2011, alongside Doug Bowman and Loren Brichter, I helped build Twitter for Mac. For several years, I was the only developer on the app, delivering features and maintaining an OS X port of UIKit.

In 2012, Twitter went 'Mobile First.' For the next few years, I helped scale development from a handful of engineers to the entire company. The iOS team grew to sixty full-time iOS developers, with hundreds of contributors. As part of the 'Mobile Architecture' team, I designed processes for massive parallel development on one codebase. I also built and taught a week long curriculum to get first-time mobile engineers up to speed.

When I joined Twitter, you could fit everyone around one large lunch table. I left shortly after the IPO, a company with over 3,500 employees.

HBO's Silicon Valley

I was a technical consultant on the second season of Silicon Valley. In addition to answering questions in the writer’s room, I built an app used by the cast and crew.