You can use custom code in:
Simulations on your development computer.
Applications that you deploy on external hardware.
Untrusted custom code, custom targets, or callbacks have risks. For example, unintended modification of your design, unauthorized acquisition of sensitive code and data by third parties, and unapproved destruction of data.
Best practices for exchanging sensitive code and data with a supplier or customer are:
For code packaging, use a secure container that supports encryption such as an Open Packaging Conventions (OPC) container.
For file transfer, use a secure transfer protocol such as HTTPS or SFTP.