Stubs with TODOs for staking out an interface to be implemented later and the like. Almost always doing "git add -p" is a good way to jog your memory about these. They can be committed but probably shouldn't survive until a merge into master.

A todo file entry for items which are heftier and/or not likely to be returned to today. My todo files are date-based so I try not to add todos for items with a time horizon beyond about three days in the future. I also try to keep these files small enough to actually get through in a day.

A single wish list/ideas file. Keep it in approximately priority order and pull items from the top when you finish your daily todos. This is also often feature-based so a single line might generate a bunch of tasks. Biased towards a personal backlog instead of "just add to JIRA/Trello/whatever" to avoid eternal agile deprioritization hell.

Works fine for me, though of course I'm not out here writing Redis either.