CPPUnit - CppUnit is the C++ port of the JUnit framework for unit testing.
Toxiproxy - Toxiproxy is a framework for simulating network conditions to prove with tests that the application doesn't have single points of failure.
Google Test - Google Test is a unit testing for C++ programming language that is based on xUnit architecture.
Spock - Spock is leave / vacation tracker for Slack
Criterion - A dead-simple, yet extensible, C test framework.
Cantata - "Module testing early during development is becoming more important due to the increasing complexity of software.