Learn what a HyperLogLog is and how you can use it to count billions of unique things.
Learn how to use Test-Driven Development to write better software in our newest Upcase trail.
How to fix the “Compiled slug size: 500.6M is too large (max is 500M)” error when trying to deploy your Heroku app.
Simplify and clarify your code by carefully choosing abstractions.
Getting started with Action Mailer and Active Job.
let
can lead to bloat. Be careful.
Paperclip is affected by CVE-2016–3714 if used with ImageMagick 7.0.1-0 or earlier.
There is no need to upgrade Paperclip in light of CVE-2016–3714. You may choose to upgrade ImageMagick regardless.
A look under the hood at how blocks and procs are used in Ruby.