Ever look at a smelter and think "Why's this thing got 100 iron plates just sitting it it? I wish I could tell it to only keep like, 5."?
Then this is the answer. Re-Buffer lets you re-define the buffer sizes on Assemblers, Chem Labs, Re-fineries, Particle Colliders, and Re-search labs- and possibly more in the future (probably miners).
It does this by re-placing the highly-efficient constants in the game's original code with values loaded from a config file- and then over-paying the performance cost by re-writing and re-optimizing all of the code around it. Over all, your game should actually run at least as fast, if not faster by using this mod. At least, until the devs get around to rewriting these sections themselves.
As a note, part of the speed gain is by allowing certain mechanical edge-cases to just happen, as well as changing certain behaviors. Notably...
As I'm sure you've noticed, lab towers are kind of silly, passing materials up and then passing jello back down. As an optional additional optimization, you can choose to have all of the labs on top of the base lab simply increase the base lab's speed rather than act as separate labs.
Upon loading a save with this setting enabled (and RythmnKit installed), we'll forcibly transfer all items back down to the base of the tower, and internally mark all of the higher labs as the base lab's speed-boosting hat. This trades the expensive Active-Lab code for massively cheaper Hat-Maintenance code- all without making your save game incompatible with vanilla.
RythmnKit is a modding toolkit that offers protos-modding, game-load-event, and game-save-event helpers. After all, tick-speed code is difficult to write and, due to manual optimization, even more difficult to maintain. Inspired by Factorio's modding structure, it aims to handle all of the complicated parts of a proto mod (like syncing the protoDesc into the save file) for you, while also providing a lot of convenience for other mods that need to handle entity components and re-interpret save files.
It also might not yet be re-leased. If it isn't, please look forward to it.