I was going to say some things regarding why conda environments as-is are a no-go for me based on work experience, but I’m not diving into it as I think it’s a bit distracting.
I will say I’m interested in seeing what having Jupyter standardize on Hatch does for this.
No pressure. 
(Still slowly working towards it, BTW).
For other people’s benefit, this last came up in Creating a standalone CPython distribution . This is something else I would like to see solved upstream, but I have to clear some space in my schedule to start tackling it.
Short version:
- PEP 665 – A file format to list Python dependencies for reproducibility of an application | peps.python.org got rejected (search around here for the threads on the topic and PEP).
- I’m working towards making GitHub - brettcannon/mousebender: Create reproducible installations for a virtual environment from a lock file be an opinionated PoC for wheels-only lock/pinned dependency files
- Need to review PoC: Metadata implementation by dstufft · Pull Request #574 · pypa/packaging · GitHub for parsing metadata
- Need to do a new release of mousebender for PEP 691 (and probably PEP 700 soon)
Long version: you know where to find me.
https://pyup.io beat you to the name.
I’m hoping that once we have pre-built binaries for CPython releases I can get something like this going with the Python Launcher for Unix.