The Problem:
Minecarts are useless because they are slow and can't be linked together!
The Solution:
Linkart! While Linkart doesn't solve slowness, it does solve the second issue! By using a simple chain, you can link minecarts together and have them follow each other till the end of days!
FAQ:
What's the difference between this version and the older one?
Since version 5.0.0, most of the mod has been rewritten to make the cart movement smoother. There are also additional features like chunkloading and linkart:linkers tag!
How do I link minecarts together?
Just get a bunch of chains and SHIFT + RMB on your “parent” cart, and then SHIFT + RMB again on your “child” cart. Now the child cart will follow its parent!
Forge version?
Not by me. Although 1.20 works with 
Connector
Requires 
Fabric API
External resources
Project members
constellation
melontini
Author