Error reporter for TestNG.
If you put this on Maven project test classpath:
<dependency>
<groupId>io.github.solf</groupId>
<artifactId>testng-error-notifier</artifactId>
<version>${VERSION}</version>
<scope>test</scope>
</dependency>
(replace version reference with any available versions from here: https://repo.maven.apache.org/maven2/io/github/solf/testng-error-notifier/ )
then TestNG errors (exceptions) will be reported immediately to System.err and slf4j (if available) under 'testng-error-notifier' logger along with the information about the test and timestamp -- this makes tracing logs much easier if you use multi-threaded tests execution.
To easier find failure messages you can search for TESTNGFAIL