Our engineering team had long accepted slow builds as an unavoidable tax on daily work. Every morning started with a coffee while waiting for the CI pipeline to finish. After a few months of targeted changes, we reduced average build time from 18 minutes to under 9.
The improvements came from better caching strategies, smarter parallelization, and removing unnecessary steps that had accumulated over time. None of these required switching tools or rewriting our codebase.
Start by measuring, not guessing
Before making any changes we instrumented the build pipeline to capture timing data at every stage. This revealed that our dependency installation step alone accounted for almost 40% of total time, and that many jobs were running the same expensive steps repeatedly.
Once we had real numbers, the highest-leverage fixes became obvious within a single afternoon.
With clear data in hand we introduced layered caching for node_modules and Docker layers, split the test suite into parallel workers, and removed redundant linting passes that duplicated work already done locally. The results were immediate and measurable.