Pre-requisites:
'Admin' permission on the project template where a system task needs to be created.
Steps to create a system task for executing groovy script on custom objects in a project template are as mentioned below:
1. Follow the steps to create a system task for custom objects in a project template (steps 1 to 4).
2. Next, follow the steps to create a system task for executing groovy script on custom objects in a project (steps 2 to 3).
3. Once done, click on 'Create' button to complete creating a system task.
Next Article: Create a System Task - Sending email notifications specific to Custom Objects (in a Project Template)