Over five years of work experience across three jobs, I’ve developed and maintained frontend CLI tools at every single one of them. While monitoring and alerting for frontend pages and server-side applications is taken for granted, these tools need it too. This article covers everything from error handling to reporting and troubleshooting.

A few days ago, I noticed a piece of code where the line-height (1.7rem) equaled the height (1.7rem), and the font-size was 1.1rem. On iOS devices, the text was vertically centered, but on Android devices, the top and bottom gaps differed by 1px (I couldn’t actually tell if it was exactly one pixel – I was guessing).

Since our company had a website without a corresponding mobile version, we needed to display a download bar at the bottom when the website is accessed from a mobile device. Clicking the download bar needed to meet the following two requirements:

1. If the app is already installed on the device, attempt to open the corresponding app;
2. If the app is not installed on the device, redirect to the download page for the corresponding operating system.