As explained in [[ https://www.softwareheritage.org/2017/03/24/list-the-content-of-your-favorite-forge-in-just-a-few-steps/ | softwareheritage.org/2017/03 ]], it's possible to contribute listers for other source code hosting services than GitHub and BitBucket. Since GitLab was not mentioned, please allow me to just put this "onto the radar", so to speak.