Ask HN: Web frameworks – which less popular frameworks are you using and why?

Many popular programming languages today have one or two web frameworks that dominate usage in that language over other web frameworks for the same language. - Python: Django, Flask - Ruby: Ruby on Rails (RoR) - PHP: Laravel - JavaScript: ReactJS I think it's nice to hear are about lesser-known web frameworks not often in the spotlight. If you are using a lesser-known or less popular web framework, what made you choose the framework? What do you like (or dislike) about the web framework you use?