I'm a little confused as to how this improves on GNU units, which seems to support far more:

    $ cat .units
    period(len) units=[m;s] 2pi*sqrt(len/gravity) ; (period/2pi)^2 * gravity
    $ units
    2980 units, 109 prefixes, 97 nonlinear units
    
    You have: period(20cm)
    You want: 
            Definition: 0.89729351 s
    You have: period(20cm)
    You want: ms
            * 897.29351
            / 0.0011144625
    You have: period(2ft)
    You want: ms
            * 1566.5419
            / 0.00063834872
    You have: 5 GiB
    You want: bytes
            * 5.3687091e+09
            / 1.8626451e-10
    You have: 5 hundred million
    You want: 
            Definition: 5e+08
    You have: tempF(100)
    You want: tempC
            37.777778

is it supposed to be a competitor? learn how to use a new language? I don't get it.

I like the idea of keeping units, but I'm not sure this makes things easier:

    ≫ V * A / J
      V × (A / J)
       = 1 V·A/J

    You have: V*A/J
    You want: 
             Definition: 1 / s