This is the GitHub home of the TEI Special Interest Group "TEI for Linguists" (LingSIG).
The pinned TEI repository is a fork of the Text Encoding Initiative Consortium's repository containing the TEI Guidelines. Selected branches of that repository are processed by the Jenkins continuous integration service maintained by Peter Stadler at the University of Paderborn.
The original home page of the LingSIG was part of the TEI Wiki. The content of that wiki is in the process of being transferred to a GitHub-based wiki, located at https://github.com/LingSIG/TEI/wiki (part of our mirror of the TEI-C Guidelines repo, mentioned above).
Some resources are still present at the LingSIG project at SourceForge (years ago, SF was the home for open-source development, hosting the TEI Guidelines among other valuable projects).