Unlike the v2.008 changes, the v2.010 changes were largely algorithmically generated. Algorithmic means that e.g. the new “a-caron” glyph is made by copy/pasting parts of the existing “a” and “s-caron” glyphs. Similarly, “superscript 4” is a scaled and translated “regular 4” and “union” is roughly an upside-down “intersection”, after accounting for any italic ‘lean’.
That program is mostly one-off textual grunt-work before and after the
tool converts fonts between binary and textual formats. It’s probably not very
interesting, but I’ve linked it anyway for reproducibility.
How to get or use these fonts hasn’t changed. If you just want the TTF files, run
git clone https://go.googlesource.com/image
and copy them from the subsequent
Alternatively, they are also mirrored at
Go Regular, Go Mono Bold Italic and Go Smallcaps Italic.