Items are preceded by the Rebirth version they where either most recently adjusted or added with.
Mods are generally added to the Extensions in the game's route directory.
1.30: Mods can be subscribed to via the Steam Workshop.
Mods can also be found on the Nexus website.
An up-to-date list of many mods, and their status, can be found on the
3.53: Loading order of mods (AKA "Extension ") can follow defined dependencies.