Monthly Archives: November 2019

Testing in Production with Feature Flags

By William Imoh

In November of this year, Instagram introduced a new feature to remove likes from your Feed. They chose to roll out this feature gradually and test in production to fully understand the impact of their decision. How do users react? Does it impact the way they use the application? Does it impact their satisfaction? Does it cause abandonment? How does Instagram achieve the magic of testing in production and how can you follow suit.

How do you manage feature flags? How do you do testing in production with multiple features being toggled? How do you automatically aggregate this data? How will gradual releases be handled? How do you segment users to and decide who receives the feature? In this post, you will learn how to implement feature flags to answer these questions.

What are Feature Flags?

Features flags are simply a technique in which toggles are used to conditionally release features to end-users of a product. At its base, feature flags are programmatic con


Javascript End-to-End Testing With Testim: Intro With Examples

By Shawn Jaques

This post is an introductory guide to JavaScript end-to-end testing, using a tool called Testim. End-to-end testing (or E2E Testing, for short) is one of the many types of automated tests that currently exist for web applications. This type of testing occupies a somewhat peculiar place in the whole automated testing scenario. While it’s arguably one of the most important types of testing, it’s also one of the most misunderstood. Due to that, it’s not used as much as it should be. And that results in developers and software organizations missing out on the benefits it can provide.

This post is an attempt to solve that problem. We’ll offer an introductory tutorial to end-to-end testing in JavaScript applications, using Testim as the example tool. We’ll begin by quickly defining end-to-end testing so that you can understand its place in a complete testing strategy.

With that out of the way, we’ll proceed to the practical p


Build a Meal Ticketing App with GraphQL and Apollo React Hooks

By Chris Nwamba

I was at a conference this year and they handed attendees meal tickets for the after-party. It was a super amazing conference and I loved meeting everyone there, but dang… I forgot my meal ticket at the hotel and was starving while everyone else ate at the after-party! They served good looking milkshakes and the best could do was stare helplessly.

Why am I telling you about how I almost missed out on a great after-party dinner? How is this related to React Hooks and Apollo? It’s not. However, I did end up building a meal ticket tracker and I used GraphQL Apollo React Hooks – so you get it.

A meal ticket tracker allows you to issue digital meal tickets to attendees and not rely on paper tickets. You can still give them the ticket, but also have a system that tracks if the ticket has been used or not. When an attendee is served a meal, you can invalidate the ticket and the ticket cannot be reused. This way, attendees that forget their tickets can use an ID like bad