The document discusses testing strategies for the ACE open source project. It describes ACE and its testing challenges due to its large codebase and distributed development. It then outlines a 4-step policy developed by ACE to prioritize testing, focusing on core components and called code. This policy reduced untested functions from 275,000 to under 3,000. The document also introduces Coverity Test Advisor and how it was used by ACE to define and enforce this testing policy. Finally, it briefly describes Coverity's development testing solutions and maturity model.