Starring a repo on GitHub is an easy way to tell its author that you appreciate their work. It only takes one click! Stars are a good way to get a quick sense of a repository’s popularity. People get pretty obsessed with tracking stars. …

I signed up for the Advent of Code after a coworker of mine mentioned that he was doing it. I was instantly hooked on collecting gold stars. I collected my last star a few days after Christmas and thoroughly enjoyed the process. …

Does something look odd about this unit test? it('should square 4', () => { square(4); }); Sure. It’s not asserting anything! It doesn’t matter whether square is implemented correctly. So long as the function doesn't throw an exception, this test will pass. This isn’t great. The test would be much…

The open-source, open-data Old Toronto map tool can help locals discover things they didn’t know about the city’s past. — This post was co-written with Associate Product Manager Matt Breuer. Editor’s Note: In 2021, Sidewalk Labs retired the Old Toronto map tool described in this blog post. Here’s a view from Yonge Street in Toronto, looking north from Temperance, right near Sidewalk’s temporary office space. At the corner we can…

Text processing in node.js has historically been both slow and cumbersome. But don’t fret, there’s hope on the horizon! The new async iterators proposal solves the “cumbersome” problem brilliantly. But sadly, it misses an opportunity to make text processing fast, too. …

Update (2020): it is now possible to correctly type _.chain by overloading the type of this on the wrapper interface. This is how the lodash typings work. See this thread for a simple example. The typings in sections 3–7 are no longer a good way to approach to this problem. …

Our NYC Transit Explorer shows how long it takes to get anywhere in the city by bus or subway. Even during L-mageddon. — Editor’s Note: In March 2021, Sidewalk Labs retired the NYC Transit Explorer described in this blog post. There’s no greater challenge facing New York City transportation than the L train East River tunnel shutdown that could start as early as 2019 and will last 18 months. The dreaded L-mageddon will…

One of underscore.js’s most useful methods is _.pluck. It takes an array of objects and "plucks" one property out of each, returning an array of the resulting values: > _.pluck([{k1: 1, k2: 3}, {k1: 5, k2: 1}], 'k1') [1, 5] This mixing of string literals and property names is a…