Add a function to existing GO application

We are looking to add a new function to this server - https://github.com/micromdm/scep

The application already contains a function (flag) called csrverifierexec which executes an external script prior to signing the CSR. We need to add a new flag+function that will execute an external script after a certificate is generated and send the certificate information (serial number, subject, validity, etc) to an external script.