[chillfox]

I think monkey patching is a nice tool to have. I once had to deal with a vendor provided gem that assumed the product was configured in a specific way (it was not) deep in an internal method. Patching that one method was all I needed to do to get it working.

[knodi123]

exactly. And when writing a test suite, I monkey-patch at will, which makes it sooo much easier to have self-contained tests without side effects or complicated dependencies.