Leanpub. Please don't think of it as "crowdfunding" think of it as "audience building".

it looks like a great platform, even if it seems their userbase is not that big. Is that right?

(No judgement. Just curious) Why does a book need crowdfunding? Between ebooks and print-on-demand it's never been easier or cheaper to self-publish. What would the crowdfunding money be spent on?

As you said publishing is not the problem these days (usually), but writing the book will take months of work and I will also need money to buy hardware and software licenses.

Furthermore a crowdfunding campaign can help measuring interest in the project and should also help building a community before the launch.

Have you written a book before? Do you have a sample chapter?

no, first one, but I have been (tech) blogging for a while.

I am working on the ToC for now, sample chapter will be next.

What will distinguish your book over all of the other C++ books around? What is it you want people to learn from your book?

it won't be about learning C++ as there are already too many, but it will be more about optimization and performance, from low level code to design decisions.

Ideally the target won't be only experts, but also new programmers who want to learn how to write better code.

If you are writing about "optimization and performance, from low level code to design decisions" why limit yourself to C++? Won't most of what you have to say be language independent?

The author of "you don't know js" successfully crowdfunded on kickstarter

I will check this campaign out, thanks

What's it about?

C++, performance and optimization

Kick starter

Indiegogo

Patreon

edit: not in any order