Plenti is a static site generator with fast build times and a flexible frontend framework for designing ambitious user experiences. The CLI tool is written in Go, so it's fast and is downloaded as a single binary that doesn't require dependencies. The templating is done in Svelte so you can create an SPA with minimal overhead being sent to your browser and the syntax is easy to pick up for beginners.
Routing is setup out-of-the-box based on your content source. You can override this by "ejecting" core files and customizing them to your liking.
No bundler is needed, Plenti pulls in ESM support for your NPM dependencies.
The local dev server automatically watches your project for changes and rebuilds so you can write code without having to restart anything.
A flexible content source allows you to define whatever field structure you'd like, without any restrictions. There are no required or protected keys.
Find more static site generators.