Flaky Test Auto-Quarantine & Automated Defect Classification Platform

Senior Automation Engineer · Year 2 · Q8 (Previous SaaS)

Platform & InfrastructureYear 2 · Q8 (Previous SaaS)

Built an intelligent CI/CD diagnostic engine that auto-quarantined flaky tests, classified stack traces using NLP clustering, and automatically generated deduplicated issue tickets.

⚡99.8% Pipeline Reliability (Zero false PR blocks from flakiness)
⚡85% Auto-Classification Accuracy of Root Causes
⚡4,000+ Engineering Hours Saved Annually
PythonElasticsearchJira APIGitHub ActionsScikit-LearnDocker

Situation

Despite individual test optimizations, scale dictating over 50,000 daily test executions meant that even a 0.01% transient failure rate caused dozens of PR pipeline runs to fail falsely each day. Developers routinely retried entire 40-minute pipelines, burning cloud compute resources and eroding trust in test automation.

Task

Architect a zero-friction flakiness management system that detects non-deterministic behavior in real time, removes flaky tests from blocking PR gates, groups similar failure modes, and dispatches actionable tickets to owner teams.

Action

  • Sliding-Window Failure Analysis: Built a lightweight Python daemon integrated with Elasticsearch that tracked test outcome histories across a 14-day sliding window, identifying tests whose failure variance exceeded statistical noise thresholds.
  • Stack Trace Clustering Engine: Implemented TF-IDF vectorization and cosine similarity matching on normalized error logs to cluster identical underlying failures (e.g., database connection timeouts vs. dynamic element stale references).
  • Automated Quarantine & Ticketing Workflow: Created a GitHub Actions step that automatically injected dynamic quarantine annotations (@Quarantined) at build time and logged auto-deduplicated Jira tickets complete with historic log snippets, frequency graphs, and system metrics.

Result

  • Elevated CI pipeline execution reliability to 99.8%.
  • Reduced developer pipeline retries by 92%, saving over 4,000 engineering hours annually.