TeX Gyre Heros is based on URW Nimbus Sans L, kindly released by URW++ Design and Development Inc. under GFL. The Vietnamese glyphs were added by Han The Thanh. Remus Variable combines the styles of TeX Gyre Heros into a single file with axes for weight, width, and italic.
URW Nimbus Sans L is based on Helvetica, designed by Max Miedinger with Eduard Hoffmann at the Haas Type Foundry in 1957. Helvetica became one of the most widely used sans-serif typefaces in the world, valued for its neutrality and breadth of weights.
Remus Variable is released under the GUST Font License. You may use, study, modify, and redistribute this font freely, including in commercial work. The license asks that derived fonts be renamed to avoid confusion with the original; modified versions are subject to the conditions of the LaTeX Project Public License.