Explore the intricacies of building and maintaining a Continuous Delivery pipeline using GitLab CI, Docker, Nexus, and Traefik in this 46-minute conference talk from PHP UK Conference 2019. Dive deep into GitLab CI Build Pipelines to learn how to build and deploy Docker containers across development, staging, and production environments. Discover the benefits of treating pipelines as code for version control, traceability, and team collaboration. Follow along as the speaker demonstrates creating projects in GitLab, pushing code, registering GitLab Runners, configuring build pipelines, integrating MySQL services, and implementing shared configurations. Gain insights into Nexus Repository Manager, Traefik configuration, and the process of deploying to various environments. Learn about review app build pipelines, merge requests, and how to effectively manage environment history in GitLab CI.