After concluding the readiness review (1) in December 2019, detailing the upcoming architecture, I was part of the team migrating GitLab.com to route through Cloudflare (2, 3).

1: https://gitlab.com/gitlab-com/gl-infra/readiness/-/blob/3e73ec904f9ded69c6ff57072c20c640c9677bbc/cloudflare/README.md
2: https://about.gitlab.com/blog/2020/01/16/gitlab-changes-to-cloudflare
3: https://gitlab.com/groups/gitlab-com/gl-infra/-/epics/117