Is your feature request related to a problem? Please describe.
A clear and concise description of what the problem is. Ex. I'm always frustrated when [...]

Yes, users can edit YAML freely, but they don't know if it's valid before running the program.

Describe the solution you'd like
A clear and concise description of what you want to happen.

Using JSON Schema, create our YAML and JSON specific config files.
YAML files should be convertible to JSON.

Describe alternatives you've considered
A clear and concise description of any alternative solutions or features you've considered.

Ajv (Ajv JSON schema validator)

Additional context
Add any other context or screenshots about the feature request here.