{stdenv, fetchurl}: stdenv.mkDerivation { name = "units-1.86"; src = fetchurl { url = mirror://gnu/units/units-1.86.tar.gz; sha256 = "1syc4d3x1wb03hcxnz7rkgapk96biazfk2qqn2wfyx54bq829lhi"; }; meta = { description = "Unit conversion tool."; }; }