Whenever (javan/whenever) is a Ruby gem that provides a clean, Ruby DSL for defining and managing cron jobs within your application. Rather than editing system cron tables by hand, you describe scheduled tasks in a schedule.rb file using methods like every, runner, command, or rake. The gem then compiles this schedule into a standard crontab format and installs it for you, handling all the necessary quoting, environment setup, and command path resolution. It supports specifying execution contexts, output redirection, and interval offsets (e.g., “every 5 minutes between 9-5 on weekdays”). You can also write conditional logic around which jobs run on different environments or servers. Because it's integrated with your codebase, Whenever keeps your cron definitions versioned, testable, and maintainable alongside the rest of your project rather than buried in server configuration.
Features
- Ruby DSL for defining schedule tasks (e.g. every, hourly, daily, etc) instead of raw cron syntax
- Ability to define jobs with parameters, environment, command to run, etc via Ruby code
- Automatically writes crontab entries from schedule file
- Supports multiple task types (runner tasks, rake tasks, custom commands)
- Offers ability to set environment variables for tasks and customizing PATH etc
- Supports time zones, frequency options, and invoking tasks at specific times or intervals
Project Samples
