Situation: I am working as a product manager on a product that is designed and implemented by our software engineer contractors.
Due to insufficient delivery quality of the contractors and given that I have strong technical skills, my employer has decided to give me the full ownership of the product, including the design and implementation responsibility.
Positive aspect: This will allow my company to save a large amount of money and will provide me with much more responsibility since I have to perform everything on my own.
Challenge: My employer knows that I already have the skills to perform this new task (based on my previous job experience) and therefore wants to assign me this new role without a raise.
Question: How would you tactfully tell your employer that the new role you got is much more senior and deserves an adequate compensation?
PS: My employer is not specialized in software engineering and is therefore not able to assess the true benefits an experienced software engineer / software architect would provide.