[MootWoop]

Hi I'm a co-founder of Synflow and author of the website. Sorry if this is not clear about what is open source or not.

To answer your question the language, compiler, and IDE are open source: https://github.com/synflow/ngDesign We're using Xtext to develop the language. The open source version includes everything you need to design with Cx and then generate VHDL code. We also have a proprietary version that adds a Verilog code generator, exporters to third-party tools, and a C-based simulator.

I agree that a lot of tools for FPGAs are much too proprietary, hopefully we're contributing to changing that. I wish we could make it all open source but we also have to make a living :-)