Byte-oriented buffer API for Lua plugins?

[TmpFinger]

Are there any API functions that would let me read, write, and delete in a buffer at a specified byte offset?

The only thing I could find was RuneAt, but it reads a single character, and the offset is probably not in bytes.
(Edit: and not even buffer-related; turned out it works on strings.)

I'm asking because I was considering porting a plugin that I wrote for other editors initially, to Micro.

[dustdfg]

I think you need to look on micro/util https://pkg.go.dev/github.com/zyedidia/micro/v2@v2.0.13/internal/util