Do you have any examples that show that `just` is more efficient than lodash? It doesn't even have a `chunk` implementation, so it's hard to say that it's better.
The "bloat" is the result of being battle tested. A slimmer implementation would cut out edge cases that I may or may not run into. If I use Lodash, I know I'm all set.
The point of the OP was that _.chunk is 140 lines, which is apparently too much. But `just` doesn't even support chunk(), so it's unclear what the advantage is. Sure, you can theoretically spend your time crafting your own implementation, but why? For the self-satisfaction? I'd rather just get on with my work.
Here's the one you referenced, lodash.chunk: https://unpkg.com/lodash.chunk – 140 lines after removing comments and whitespace.
That's pretty small compared to a lot of the lodash utilities. Try spot-checking a few on unpkg.
I prefer angus's `just` utilities: https://github.com/angus-c/just