It might sound kinda weird, but I see Azure DevOps Boards (or similar) an ideal system for implementing this. Why: 1) Small notes via User Stories (or tasks) 2) Has linking capabilites 3) Has TAGs 4) Visual representation of LINKS 5) Most of the grind associated with doing this via other systems is removed 6) Free & you can download the data in .csv if needed

Thoughts?