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Huginn is a web-based scheduling service that runs workers called Agents. Each Agent performs a specific function, such as sending an email or requesting a website. Agents generate and consume payloads called events, which can be used to chain Agents together. It's easy to deploy Huginn with just one click using the Deploy to Heroku button. You can extend Huginn by using one of the many available Agent Gems, or by creating your own. The creator of Huginn, Andrew Cantino, started the project in 2013 to scratch his own itch.