CQSE Workshop - Fast Feedback from Long-Running Tests

Raphael Nömmer & Fabian Streitel

Test Selection for Ever-Growing Test Suites


As software systems grow, so does the number of their tests. As a result, we increasingly often encounter test suites that run hours or days, which is painfully slow. To get fast feedback about new bugs despite slow tests, we can run a subset of all tests more frequently. If this subset is chosen well, these tests identify most bugs very quickly.

This approach heavily depends on the selection of frequently-executed tests. We developed two different approaches for selection:

  • Test-Impact Analysis
  • Pareto Optimization

In this workshop, we first present the key ideas and research studies for both, and then demo them live in our analysis tool Teamscale.

Attendees' voices

»A very good presentation and live demo!«

»Already knew Pareto-Optimization by CQSE, the live demo was great for deeper understanding!«


  • Fabian Streitel - Leads the Test Intelligence Team at CQSE and has successfully set up Test-Impact Analysis and Pareto Optimization with many customers.
  • Raphael Nömmer - Did research on Pareto Optimization and uses both approaches every day with our customers.
  • Thomas PettingerUses Test-Impact Analysis and Pareto Optimization every day with our customers as part of the test Intelligence Team.

We will repeat this workshop on November 8, 2023 (10:30-12:00 CET) in German with the same content. 




Raphael Nömmer