You could go old school and use something like redmine or trac. I've played with both for that purpose, but I get bored easily. They can both use sqlite for storage.

https://en.m.wikipedia.org/wiki/Comparison_of_issue-tracking...

https://en.m.wikipedia.org/wiki/Issue_tracking_system

https://www.redmine.org/projects/redmine/wiki/RedmineCalenda...