Functional CSS (FCSS)

August 20, 2013

We’re big fans of functional programming at Wealthfront. Emphasizing immutability and functional style means fewer “surprises” because side-effects are limited or nonexistent. We can quickly build up large systems from discrete, focused components by way of composition. Applying such principles is straight forward in most languages, even if they’re not functional by definition, but the… Read more

ActiveJsonEntity: Bridging the gap between Rails and Java

June 13, 2013

We have a service-based architecture here at Wealthfront. Instead of our Rails layer talking to a database, it makes RPC calls over HTTP to a collection of services that send and receive JSON. Without a database we can’t use ActiveRecord, and all the niceties it provides. In their first incarnation, our models were plain Ruby… Read more

jQuery.Deferred is the most important client-side tool you have

December 04, 2012

jQuery’s introduction of $.Deferred() is one of the library’s most powerful additions in recent history. It’s not a new idea, but it merits an introduction now that it’s available to thousands of client-side developers. At its core, the Deferred pattern is a simple but powerful tool for the management of asynchronous processes. As we all… Read more

On the humanity of mathematical models

November 19, 2012

A great deal of care is spent designing our algorithms and models at Wealthfront. The work of Qian Liu and others is put through trial runs against historical data, peer reviewed by members of the company, and vetted by outside advisors in the academic and private sectors. Along with Dr. Malkiel, we also work with… Read more

Scrolling the Z-axis with CSS 3D Transforms

March 22, 2012

We recently decided to make a gimmicky appeal to designers in the hopes that they’d come talk to us. We knew we wanted to do something a little flashy and cutting edge, so CSS 3D Transforms seemed like a good place to start. Ultimately I decided I wanted a page that would allow users to… Read more

Converting dynamic SVG to PNG with node.js, d3 and Imagemagick

December 22, 2011

Visitors to Wealthfront might notice we’re using SVG to render the risk meter in our questionnaire, as well as your performance projection and other charts. We build our visualizations using d3.js, a fantastic library that provides just the right amount of abstraction on top of SVG to allow us to develop robust visualizations quickly. SVG… Read more