no-herd maintainer-needed@gentoo.org In a nutshell TomsFastMath is meant to be a portable fixed precision math library geared towards doing one thing very fast. Exponentiations. The modular kind. Like what you find in RSA and DH. Though TomsFastMath (TFM) is not limited solely to doing RSA or DH. It's generic enough to be used for other projects such as ECC as well.