Strict type some of `cargo`

[JamieMagee]

What are you trying to accomplish?

Anything you want to highlight for special attention from reviewers?

How will you know you've accomplished your goal?

Checklist

• [ ] I have run the complete test suite to ensure all tests and linters pass.
• [ ] I have thoroughly tested my code changes to ensure they work as expected, including adding additional tests for new functionality.
• [ ] I have written clear and descriptive commit messages.
• [ ] I have provided a detailed description of the changes in the pull request, including the problem it addresses, how it fixes the problem, and any relevant details about the implementation.
• [ ] I have ensured that the code is well-documented and easy to understand.

[randhircs]

@JamieMagee Required specs are failing, you may like to fix it.