Another option is plzip (parallel Lzip, an official part of Lzip).

> decompression of ungoogled-chromium from the LAN completes in 2.4s for
> gzip vs. 7.1s for lzip.  On a low-end ARMv7 device, also on the LAN, I
> get 32s (gzip) vs. 53s (lzip).

With four cores, plzip would beat gzip in the first case.
With only 2 cores, plzip would beat gzip in the second case.

What's left to do to implement plzip support?  That's the good news:
almost nothing!

- On the Lzip binding side, we need to add support for multi pages.
  It's a bit of work but not that much.
- On the Guix side, there is nothing to do.

Cheers!

-- 
Pierre Neidhardt
https://ambrevar.xyz/