When you say "use your code in your resume" you probably mean "brag about your (small) part in integrating the new building's tech." Don't include the actual code in your resume, duh.

You probably have a section of your resume that mentions individual accomplishments. Say something like this:

I created a Python module to help interface with Honeywell building automation technology. Deploying it saved some time bringing a new $100mill building into service.

See how it goes?

1. What you did (without exaggerating, but with mentioning the brand of tech)
2. Why it was helpful.

When you say "use your code in your resume" you probably mean "brag about your (small) part in integrating the new building's tech." Don't include the actual code in your resume, duh.

You probably have a section of your resume that mentions individual accomplishments. Say something like this:

I created a Python module to help interface the company-wide Framis system with Honeywell building automation technology. Deploying it saved some time bringing a new $100mill building into service.

See how it goes?

1. What you did (without exaggerating, but with mentioning the brand of tech)
2. Why it was helpful.

This sort of thing helps emphasize that you care about your employer's success and have the creativity and initiative to help out. A person reading your resume is asking herself, "Will Matt be a good addition to our team?" This kind of thing helps them answer "yes."

And, if the prospective employer doesn't like creativity and initiative, it may save you time: the company's a bad fit for your skills and personality.