Never heard of M4 before and, lo and behold, of course HN has a discussion of it: https://news.ycombinator.com/item?id=34159699

The author discusses Logica vs. plain SQL vs POSIX.

I’d always start with dbt/ Sqlmesh.

The library you’re talking about exists: dbt packages.

Check out hub.getdbt.com and you’ll find dozens of public packages for standardizing sources, data formatting or all kinds of data ops.

You can use almost any query engine/ DB out there.

Then go for dbt power user in VS Code or use Paradime and you have first class IDE support.

I have no affiliation with any of the products, but from a practitioner perspective the gap between these technologies (and their ecosystems) is so large that the ranking of value for programming is as clear as they come.