In order to continue to support the modules, develop new products (including hardware) we are not making the modules open source and a charging for the set. This includes the modules themselves and anything we include as updates to the set. With that said, most of the underlying technology we are creating will be made open source. The idea is that that folks should be able to access much of the back-end tech for research or developing their own work, but the final designs will be our own proprietary technology. Most VCV Rack companies are typically just one person, so in order to continue to develop this with three people, even though it is a passion project, we had to charge a small fee (this also allows us to offer support in the form of direct communication and a website with manuals, video tutorials, example patches, etc.).
We agonized over this, but given the current climate of piracy and exploitation by bad faith actors (for example mutable clones that are intentionally under-pricing the modules they make to sink their competitors, people selling clones before emilie sells out the first the release-her only request, and the ever-present threat of behringer), we decided make the module suite a commercial release. I have been requested not to list prices (which is fair because this board is about discussion, not selling products), but we have intentionally made the barrier of entry low. You can find out more about pricing on our website, or by sending me a message.