This fabric mod adds a new type of repeater that can be placed on walls! These vertical repeaters function identically to normal repeaters, but of course, vertically. They are powered by the block below them and power the block above them, or vice versa depending on how you place them. You can change the delay by right-clicking and lock them by powering them from the sides with normal repeaters. They can be powered by power sources (redstone block, redstone torch, lever, etc.), powered blocks, and powered redstone dust. They must be placed on the side of a block, and will break if that block is broken. See the Images tab for clarification.
UPDATE: Now with vertical comparators!
The crafting recipe is the same as a normal repeater, but rotated 90 degrees:
I intend to add redstone dust eventually.
REQUIRES FABRIC API!