Test::Builder – Backend for building test libraries – metacpan.org

• https://metacpan.org/pod/Test::Builder
• https://metacpan.org/pod/Test::Simple
• https://metacpan.org/pod/Test::More
• https://en.wikipedia.org/wiki/Test_Anything_Protocol – TAP

Test::Simple and Test::More have proven to be popular testing modules, but they’re not always flexible enough. Test::Builder provides a building block upon which to write your own test libraries which can work together.