[setpatchaddress]

The derogatory and inaccurate use of “monkey patch” to describe adding methods to an open class identifies you as a Python advocate, so grains of salt applied, but:

I can’t speak for this particular Rails usage, but one of the most powerful things you can do with Ruby is build domain-specific languages without modifying the language itself. *This is a core feature of Ruby.*

The criticism you’re making is one of the Rails DSL — there’s nothing in Ruby preventing you from instead writing account.desposit(Dollar.of(100)).

Put another way: This is like people criticizing RISC-V for not having multiplication in the core ISA — they don’t seem to grasp that RISC-V is an ISA construction set. Ruby is a language construction set.

[futharkshill]

"monkey patch" is frequently used by Rubyists without anny derogatory meaning.

[michaelcampbell]

True, but it was taken on by the ruby community as a badge of pride after being used as a slur by the aforementioned other community, IIRC.

[zdragnar]

I first heard the term in reference to how mootools messed with prototypes of JavaScript built-ins; at that time, I had no experience with either python or ruby.

Whatever context the term may have originated with, it far outgrew those origins. I definitely don't instinctively think of python programmers snubbing ruby when I hear the term.