Case Studies

Cut PR checks from 40→9 minutes

How we optimized a complex CI pipeline to reduce feedback time and increase developer satisfaction.

Problem

A client's CI pipeline was taking 40+ minutes per pull request. Developers were frustrated, context switching was rampant, and the team struggled to maintain flow state.

DETA™ Approach

We analyzed the pipeline and identified bottlenecks:

  1. Sequential test execution: Tests ran one after another
  2. No caching: Dependencies were downloaded on every run
  3. Heavy static analysis: Multiple linters ran serially
  4. Inefficient Docker builds: No layer caching

Solution

We restructured the pipeline to run in parallel:

  • Split test suites across multiple jobs
  • Implemented caching for dependencies and build artifacts
  • Moved non-critical checks to post-merge
  • Optimized Docker builds with multi-stage caching

Outcomes

  • CI time: 40 minutes → 9 minutes (77% reduction)
  • Developer satisfaction: Increased PR frequency
  • Change-failure rate: Unchanged (quality maintained)

Metrics

Metric Before After Change
CI time 40 min 9 min ↓ 77%
PR checks/day 12 28 ↑ 133%
Developer feedback Negative Positive Improved