TypeTogether was asked to expand 21 Helvetica weights into an extensive character-set that involved adding over 1800 glyphs per font, including Latin B, Cyrillic and Greek scripts. A mix of available commercial tools, custom Python programing and extensive multiple master use was necessary in order to make this complex project a bit more manageable.
Further 3 other typefaces, Impact, Serlio and Univers, were later also expanded to the custom encoding.