https://www.mikeperham.com/2012/08/26/the-sidekiq-experiment...
I sell closed source Pro and Enterprise focused feature packs for my OSS projects. This is known as "open core".
My first full year in 2013 I sold $85k.
I'm in the millions ARR now.
Mike's story was a lot of inspiration for me, and I think licensing + cloud-ifying your opensource projects are a ton more viable than hoping for Patreaon or other platforms to pay you. Self-bootstrapped indiehacker style was great for me, but it does require a lot of up-front time and commitment in seeing it through. Upside is that it's not monopoly money being dealt with, and everything is on your terms.
With the knapsack_pro version I focused on common needs of users and there was simple validation method to verify if particular feature was needed. People just pay if it brings value.
In case of free open source tool, people tend to want something but you don't know if they actually will you use it and sometimes people demand a thing while you have to put the hard work.
When you do paid version of your tool then somehow people are polite. :)
Nowadays I have also support for running parallel tests in JS.
More at https://knapsackpro.com and here is detailed technical explanation how it works https://docs.knapsackpro.com/2020/how-to-speed-up-ruby-and-j...
I appear on various podcasts, e.g. The Changelog, regularly and talk about things there too. I'll be on FounderQuest in the next week or two.
Could you please point to how licensing works in open source. I get the user has to buy license - is it like a key that talks to your server or how do you stop the abuse etc ?
If you have $1m in sales and $1m in unlicensed usage, do you have a problem?
In general though you should focus on building value, not building walls around your product.