This document discusses techniques for continuous integration (CI), including: 1. CI involves integrating code changes frequently and automatically through a shared code repository with automated builds and tests. This helps catch errors early and prevents integration issues. 2. As codebases grow larger, builds can slow down, hindering developer productivity and ability to deliver features quickly. 3. Various techniques can help speed up slow builds, such as splitting codebases, using faster hardware, optimizing tests, isolating dependencies, parallelizing builds, and choosing lightweight development containers. Monitoring build times is also important.