I think the word "using" here is doing a lot of work. When talking about an entire application, I think of "using" it as being, well, using the application. But

I think the word "using" here is doing a lot of work. When talking about an entire application, I think of "using" it as being, well, using the application. But what I think we're talking about here is "using" the application code by selling it as your own product. I recognize that "open source" is ok with that second way of "using" the code, but I do think it's meaningfully different.