Nice product but it may have been better to release this as a opensource product because there will always be a fear that if your company goes bottoms-up, those companies who used your platform will be left high and dry.
The thing is, making Anvil open source now would virtually guarantee that outcome.
The market has spent the last few years demonstrating that the sustainable number of large companies whose main product is open source is...One. (Red Hat, if you were wondering.) Even trying to become that kind of company requires a highly speculative VC-fuelled trajectory, which is famous for turning sustainable 100m-scale companies into 1% unicorns and 99% rubble.
Even Docker, which utterly transformed its target market, is barely making any revenue ($25m/year on a $1.3bn valuation). All its value is busily being subsumed into Kubernetes, itself a loss-leader from a company (Google) that makes all its money from something else.
Anvil-the-company is sustainable, profitable, and growing, and Anvil-the-product is getting better all the time, because we charge for what we produce. We would love to be able to give it away and keep doing that - but basically, we can't.
What about releasing it like how Node.js was released? that is a full web platform but one which uses Python instead of Javascript? and with a repository for packages which people can download and use or even contribute to?
Ultimately unless there is an active and vibrant ecosystem, there is very little reason to consider your platform - especially when there are alternatives like Node.js, Django etc.
Also, for me I will be concerned about how I will integrate Anvil with third-party libraries needed for things like reporting, authentication/authorization, E-commerce etc.
Sure, the GUI wizard is not there for Django but what if someone were to develop such a wizard for Django? or what if someone were to say that it is best to stick with Django / Vaadin/Ketura/.NET/Go/Rocket.rs even if it takes another 25% more time to develop in because the ecosystem is much bigger and we can predict with more confidence that Django / Vaadin/Ketura/.NET/Go/Rocket.rs is going to be around?
HOWEVER, if your product was available open source, is a lot easier to setup and use than Django/Ketura/... (you could provide it as a docker image) and you had a business model where you provide hosting for that solution (similar to Heroku) and/or paid support, you may end up making more money because a lot more people would use your platform - lot more than your current model which very few companies will risk purchasing.
That's my fear also. Emulating GUI's in web browsers takes a ship-load of code. Therefore, it needs strong maintenance prospects to safely last into the future.
