Though Cron has been around since the 1970s, it is often still a perfectly viable, incredibly robust way to run scheduled jobs for your web application – in particular if you deploy your app to a single dedicated server or VPS.
Whenever is a command line utility, written in Ruby, that lets you declare your Crontab entries using the very human-readable Ice Cube DSL, and that includes related utilities to actually write out to your Crontab based upon these human-friendly source files. The benefits for your project are twofold. First, you get to define your Crontab entries in a language that is natural to read rather than in the famously obscure and forgettable native syntax. Second, you get to keep your schedule definition within your project tree so that it becomes, in effect, integrated with your application rather than something managed separately with your infrastructure.