Shameless plug -- try out Documize if you are looking for Confluence alternative.
It's built with Go and EmberJS.
* Designed for tech and non-technical user alike
* Cloud or self-host (single binary deployment)
* Open source core
* Markdown, WYSIWYG with open sourced "connectors"
* Built-in approval and versioning capabilities (no paid add-ons required)
* Secured for internal and external participants
* Opinionated content organization approach