Mixpanel’s web UI is built out of small pieces. Our Unix-inspired development philosophy favors the integration of lightweight, independent apps and components instead of the monolithic mega-app approach still common in web development. Explicit rather than implicit, direct rather than abstract, simple rather than magical: with these in-house programming ideals, it’s little surprise that we continue to build Single-Page Applications (SPAs) with Backbone.js, the no-nonsense progenitor of many heavier, more opinionated frameworks of recent years.
On an architectural level, the choice to use Backbone encourages classic Model-View designs in which control flow and communication between UI components is channeled through events, without the more opaque declarative abstraction layers of frameworks such as Angular. Backbone’s greatest strengths, however – its simplicity and flexibility – are a double-edged sword: without dictating One True Way to architect an application, the library leaves developers to find their own path. Common patterns and best practices, such as wiring up Views to listen for change events on their Models and re-render themselves, remain closer to suggestions than standard practices, and Backbone apps can descend into anarchy when they grow in scope without careful design decisions.
We recommend setting up work queues and batching messages to our customers as an approach for scaling upward server-side Mixpanel implementations, but we use the same approach under the hood in our Android client library to scale downward to fit the constraints–battery power and CPU–of a mobile phone.
The basic technique, where work to be done is discovered in one part of your application and then stored to be executed in another, is a simple but broadly useful; both for scaling up in your big server farm and scaling down for your customer’s smartphones.
Now if something wonky happens, I can easily modify the library code. We also get the added benefit of broader platform support – you can use mixpanel.com on your mobile device and it works perfectly.
Actually picking the library was a little tricky. We were lucky – highcharts was released right when we started looking and it has performed admirably. There are a few other good choices though, and I will go into all of them in some depth.