I don't see Buf's play as being about scale or performance, but rather developer experience. I think that that with the right tooling, the developer experience of strong schemas with code generators can far surpass JSON/REST. If that happens then the performance/scalability benefit is just a bonus.

Will people pay for it? That's not my area of expertise. But, I would note that Vagrant started out as a collection of Ruby scripts for wrangling existing VM products, which probably few people imagined would be something people would pay for. And just this morning, Hashicorp went public at a market cap of $18.5B. It is possible to build a business around developer tools. Not easy, certainly, but possible.

> I hope you don't have a lot of capital locked in this

Like any intelligent angel investor, I always assume I'll lose 100% of my investment and size them appropriately.