GitHub - logseq/logseq: A privacy-first, open-source platform for knowledge management and collaboration. Download link: http://github.com/logseq/logseq/releases. roadmap: http://trello.com/b/8txSM12G/roadmap privacy-first, open-source platform for knowledge management and collaboration.
There’s Obsidian already and Logseq is also quite popular and it’s OSS unlike Obsidian.