I have. Obviously it's not possible to do this completely in C#, but my team has moved over to using Option, Try, and Either types for values that might be nul

I have. Obviously it's not possible to do this completely in C#, but my team has moved over to using Option, Try, and Either types for values that might be null or throw exceptions. We've noticed a reduction in what we all knew was the single most common bug: null reference exception. It also reduces cyclomatic complexity [1], which is a fairly well understood measure of complexity and therefore bugs. Anecdotally I've noticed a reduction in these kinds of issues when using languages that use non-nullable references by default (F#. Haskell, etc.). I find I am much more confident as a programmer when nullable references aren't the default. Actually a few days ago we had our first null reference error in F#, and it was because the record type passed to an F# function was instantiated in C#. If you think about it, the idea that a statically typed system lies to you about the contract that a value will honour is always going to be a source of bugs. It takes static languages back into the realm of dynamic languages. [1] https://en.wikipedia.org/wiki/Cyclomatic_complexity https://en.wikipedia.org/wiki/Cyclomatic_complexity