My Sidekiq project isn’t just about building the best background processing framework for Ruby, it’s also a venue for me to experiment with ways to make open source software financially sustainable for the developers who work on it hundreds of hours each year (e.g. me). Let’s review.

When Sidekiq was first released in Feb 2012, I offered a commercial license for $50. Don’t like Sidekiq’s standard LGPL license? Upgrade to a commercial license. In nine months of selling commercial licenses, I sold 33 for $1,650. If you figure I spent 300 hours building Sidekiq, that’s less than minimum wage. Result: failure.

In October last year I announced a big change: I would sell additional functionality in the form of an add-on Rubygem. Sidekiq Pro would cost $500 per company and add several complex but useful features not in the Sidekiq gem. I do little to market it, don’t buy ads or sponsor anything; it’s sold purely through word of mouth and mentions in the Sidekiq documentation.

In the last year selling Sidekiq Pro, I sold about 140 copies for $70,000. Assuming I’ve spent 700 hours on Sidekiq so far, that’s $100/hr. Success! Sales have actually notched up as Sidekiq has become more popular and pervasive: my current sales rate appears to be about $100,000/yr.

This isn’t retirement money but it is very respectable money for a side project and one I could make into a full-time job if desired. It makes supporting Sidekiq something I enjoy rather than a chore I dread: in the last year I’ve released 34 versions of Sidekiq with lots of new features, bug fixes and tons of contributions from the community.

My one open question is how to market Sidekiq Pro now? Sure, I could fill the Sidekiq website with boring whitepaper case studies and sell 24/7 support but… ugh. So far my best response has been at developer conferences: when I meet and network with other Rubyists to answer their questions and soothe their fears, they buy Sidekiq Pro. I wish I had the time and fortitude to travel around the world but a wife and child does not allow this flexibility.

As always, thank you to my customers for making this ongoing experiment a success and I hope the results so far encourage other OSS developers to experiment with ways to finance their own hard work.