This proof of concept project uses the PHP zend_ast_process
hook to use the AST to find function definitions and insert function calls that will open and close spans, as well as exception information.
See the DESIGN.md file for the design and more detailed information.
This proof of concept was written by Levi Morrison and Sammy Powers during Datadog's Hackathon in August 2019. Thanks to Joe Watkins for providing some feedback.