Facebook Design Resources might be a bit more popular than GitBook. We know about 2 links to it since March 2021 and only 2 links to GitBook. We are tracking product recommendations and mentions on various public social media platforms and blogs. They can help you identify which product is more popular and what people think of it.
You can have both a landing page (e.g.: www.your-project.dev) and a documentation website (e.g.: docs.your-project.dev). For creating documentation website GitBook is better fit than Gitlanding. GitBook is free for open source Projects (you just need to issue a request). - Source: dev.to / about 2 years ago
GitBook is a collaborative documentation tool that allows anyone to document anything—such as products and APIs—and share knowledge through a user-friendly online platform. According to GitBook, “GitBook is a flexible platform for all kinds of content and collaboration.” It provides a single unified workspace for different users to create, manage and share content without using multiple tools. For example:. - Source: dev.to / about 3 years ago
Spotify isn't doing anything unique here, and it's not really a marketing campaign to explain away their UI. It's more of a showcase for hiring professionals, developers/designers/etc. Facebook has a similar one -> https://design.facebook.com/. Source: almost 3 years ago
Also, read anything published by Design @ Facebook. Source: over 3 years ago
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