I maintain a fork of SRFI 122

https://github.com/gambiteer/srfi-122/

where I've added a few things that were not in the finalized SRFI,
specifically the routines

interval-cartesian-product
array-outer-product
array-assign!

I continue to think about arrays and how to use them. I'd like to get
various implementations and applications of SRFI-122 available (beyond
what I use it for) and when it looks like I don't have anything more to
add I might propose an updated SRFI with the new routines.

In that vein, if anyone would like assistance to modify SRFI-122 to run
in their favorite scheme, or to use SRFI-122 in support of their
application, I'd be glad to help.

Brad