Rails is now now not written in Ruby


I’m born and raised in Kraków, an attractive metropolis in Poland, per chance you’ve heard about it, per chance you’ve even been here. In Poland we discuss Polish, which is a terribly subtle language, it’s if truth be told thought to be with out a doubt one of the most head-10 most subtle languages to learn on the earth. In Poland, factual admire in many completely different countries, there are regions where dialects are outmoded reasonably than “the pure” bear of the language, and so in my metropolis, we private our private dialect. It’s now now not too various from Polish, but we private our particular phrases, and a particular system of claiming certain phrases. As an illustration, we are saying “czy”, which draw “three”, even supposing the lawful bear is “trzy”, but we’re admire “that’s too tense” so we preserve it easy, “czydzieści czy” (33) reasonably than “trzydzieści trzy”. The leisure of Poland is making fun of us attributable to this form of stuff, but irrespective of, it’s our dialect – here’s how we clutch to discuss.

What does it private to complete with Rails and Ruby though? Felony ask. Programming languages private dialects as neatly, by definition, a programming language dialect is “a (quite diminutive) variation or extension of the language that does now now not alternate its intrinsic nature”. It doesn’t for sure subject how exactly such variation or extension is utilized. The crucial phase is that the genuine language is prolonged and it presents extra functionality, while it’s fashioned nature and habits conclude the an analogous.

This brings us to Ruby – a programming language with open courses, where even the core functionality of the language would be prolonged by simply along side contemporary discover how to core courses, admire String or Array. This makes it very easy to bear your individual Ruby dialect!

This habitual characteristic of Ruby has been leveraged by DHH help when he created Ruby on Rails framework. The very foundation of this framework is a library known as ActiveSupport – a extensive series of core Ruby extensions, which collectively bear a Ruby dialect, an prolonged model of the Ruby language, which doesn’t alternate it’s intrinsic nature. Why is it a foundation of the framework, you most definitely can honest ask – the reply is amazingly easy: every little thing would spoil in case you tried to prefer ActiveSupport from Rails.

What does it if truth be told imply in case you most definitely can honest private in thoughts your complete Ruby ecosystem though?

Monopoly for monkey-patching

Monkey-patching is one other system of claiming that some section of code alters an unique class by leveraging open courses in Ruby. The ActiveSupport library monkey-patches many courses, there are currently 3471 LOC in its core_ext directory. Here, I’ve generated some stats:

{Array=>{:original_methods=>196, :as_methods=>251, :added_by_as=>55},
 Class=>{:original_methods=>117, :as_methods=>172, :added_by_as=>55},
 Date=>{:original_methods=>132, :as_methods=>240, :added_by_as=>108},
 DateTime=>{:original_methods=>142, :as_methods=>277, :added_by_as=>135},
 File=>{:original_methods=>236, :as_methods=>279, :added_by_as=>43},
 Hash=>{:original_methods=>182, :as_methods=>246, :added_by_as=>64},
 Integer=>{:original_methods=>148, :as_methods=>206, :added_by_as=>58},
 Module=>{:original_methods=>114, :as_methods=>165, :added_by_as=>51},
 Object=>{:original_methods=>63, :as_methods=>83, :added_by_as=>20},
 Vary=>{:original_methods=>133, :as_methods=>171, :added_by_as=>38},
 String=>{:original_methods=>188, :as_methods=>256, :added_by_as=>68},
 Symbol=>{:original_methods=>92, :as_methods=>114, :added_by_as=>22},
 Time=>{:original_methods=>121, :as_methods=>257, :added_by_as=>136}}

In the occasion you depend them all, you accept 853 occasion concepts added to the core courses.

Gaze that I’m easiest talking about the core extensions. I skipped courses from the stdlib! I furthermore counted easiest public occasion concepts. It could perchance be attention-grabbing to opinion what number of class and non-public concepts ActiveSupport provides. This could perchance be a fun excercise.

In the occasion you most definitely can honest private a library, a ruby gem, which provides this kind of serious quantity of most up-to-date discover how to the core courses, it’s excessive to maintain that:

  • You’re no longer utilizing Ruby, you are if truth be told utilizing a Ruby dialect, utilized as a library known as ActiveSupport
  • You must undergo in thoughts that the concepts that you are along side to your individual courses in your application’s code could potentially motive conflicts with ActiveSupport
  • It’s a extremely injurious thought to bear various libraries, that furthermore monkey-patch core courses, resulting from they might be able to motive conflicts as neatly

A while previously, we had somewhat a lot of ruby gem stones that could furthermore count on monkey-patching. We even had a corpulent-stack framework that used to be meant to compete with Rails. It used to be known as Merb and it furthermore had one thing admire ActiveSupport, it used to be known as extlib. As you virtually absolutely guessed – it precipitated conflicts with ActiveSupport so it wasn’t for sure feasible to exhaust both libraries in the an analogous codebase. Merb and Rails “merged” into Rails 3 though, and that’s how we don’t private “an extlib order” anymore, for the reason that library is gone. Over time, many Ruby builders engaged on somewhat a couple of gem stones private discovered the downsides of monkey-patching and easily stopped doing it. RSpec is our important instance here – a limited and problematic DSL primarily based entirely entirely on monkey-patching used to be changed into precise into an attractive, composable DSL which we serene private in RSpec.

Sadly, even supposing majority of the gem stones stopped relying on monkey-patches, we serene private ActiveSupport factual resulting from it’s this kind of fundemental phase of Rails. In spite of every little thing, the framework is written in ActiveSupport Ruby dialect!

Here’s the crux of the order though:

an API which is utilized as phase of a Ruby dialect seems to be “nicer”, extra concise and pure

Why? Because it seems to be admire phase of the language! Here is why issues admire 1.day.previously seems to be so “pure”. Rather then that it’s now now not Ruby – it’s ActiveSupport.

In the occasion you take into sage it, you most definitely can honest realize that here’s a giant advantage that Rails has over every various library on the market – it’s obtained monopoly for monkey-patching.

Ecosystem-huge implications

For folks admire me, who’re engaged on Ruby libraries, experiencing constant pushbacks and damaging feedback while you attempt and demonstrate straightforward concepts to system certain problems is factual daunting. It occurs somewhat assuredly that you just demonstrate one thing now and all you hear is “that’s too subtle”. The reason why one thing seems to be to be to be “extra subtle” is that you absolutely exhaust Ruby, with objects, and encapsulation of habits…reasonably than chucking in irrespective of you clutch to private in any class that you just happen to catch precious.

! it used to be dropped at my consideration that this paragraph makes it seem admire I’m frustrated and creates an influence that the article is toxic as I’m making Rails stare injurious – to elaborate: I’m now now not frustrated, a long way from it, in most cases I maintain tired and lose motivation, nonetheless it’s factual “a injurious day”. My device with this paragraph used to be to tell how Ruby library authors could honest assuredly feel, which is primarily based entirely entirely on my previous expertise. My device along with your complete article used to be to demonstrate what ActiveSupport if truth be told is so as that you just’d private some point of view, which I take into consideration many folks don’t private. Here is why discussing Ruby code is often tense, attributable to the shortcoming of this point of view.

In the occasion you possess in thoughts your complete Ruby ecosystem, here’s an exact order. Initially, you compete utilizing horrible Ruby with the ActiveSupport dialect – most ceaselessly you’ve lost prior to you even began coding, resulting from most Ruby builders obtained’t admire irrespective of you’re going to bear. Of us private certain expectations from Ruby libraries and in addition they’re closely influenced by their expertise with Rails and its dialect.

One more reasonably damaging implication is that Rails, by ActiveSupport, has created a huge confusion about what’s Ruby vs what’s Ruby with ActiveSupport. This has by no draw been a first rate thing. Belief me, there are folks in various programming communities who dislike Ruby when truly, they if truth be told dislike Rails! Of us confuse the 2 the full time.


Yes, and? Here is now now not an argument that can clarify monkey-patching. In the occasion you clutch to private to experiment with contemporary concepts, conclude it in isolation, in your individual codebase. In the occasion you’re feeling marvelous about what you came up with – myth a order in the Ruby tracker suggesting a brand contemporary draw addition.

This furthermore goes help to what I beforehand mentioned: monopoly for monkey-patching. It’s now now not OK that there’s this one library with particular treatment that can monkey-patch gorgeous worthy irrespective of and then a couple of of its patches can cease up in the language itself.

Technical and construct implications

I assuredly hide that monkey-patching isn’t even a sound technical solution, honest resulting from you most definitely can’t make monkey-patches, there’s lack of encapsulation and ideal boundaries and, to kind issues worse, it’ll with out problems lead to naming conflicts. Let’s spoil this down:

Lack of composability

Composability is a extremely highly fantastic system. In Ruby, it’ll be with out problems accomplished by simply utilizing objects. In functional language, you most definitely can simply make functions. What does it imply to make functionality? It factual draw that you just rob functionality X, and functionality Y, and also you switch it into functionality Z which combines the 2 in this kind of style, that X and Y are hidden (which is named encapsulation, but I’ll accept to this phase later).

Here’s why this doesn’t work so neatly in case of ActiveSupport (and monkey-patching on the full). Let’s recount you most definitely can honest private a host and also you clutch to private to structure it, ActiveSupport presents a to_formatted_s draw utilized as a Numeric core extension:

987654321.to_formatted_s(:phone, area_code: honest)
=> "(98) 765-4321"

Frigid, gorgeous? So pure, stare at this honest section of Ruby ActiveSupport dialect.

Now, take into consideration that you just most definitely can honest private to preprocess the number 1 draw or the other, per chance you most definitely can honest private to tidy it and prefer some junk. What conclude you conclude?

 "  HUH987654321  ".strip.gsub(/AHUH/, "").to_i.to_formatted_s(:phone, area_code: honest)
=> "(98) 765-4321"

OK, you’re serene covered by Ruby and ActiveSupport, let’s recount you most definitely can reside with this for a while but then you positively perceive you most definitely can honest private to validate the string (as you most definitely can honest serene) prior to doing one thing else with it. What conclude you conclude? This?:

class String
  def validate_phone_number
    # ...

"  HUH987654321  ".strip.gsub(/AHUH/, "").validate_phone_number.to_i.to_formatted_s(:phone, area_code: honest)

In the occasion you’re shaking your head that it could per chance perchance be a injurious thought then for wonderful you’re gorgeous, but wager what – folks outmoded to complete that! Certainly, I wager there are those that also conclude that! Total, the consensus in the future of the neighborhood has been for years that it’s indeed a injurious thought and a huge code smell. Most skilled Ruby builders don’t monkey-patch core courses anymore.

Lack of encapsulation and unclear boundaries

Encapsulation is excessive resulting from it lets you complete composability, pluggability, extensibility and on the full makes your code worthy more straightforward to work with. If boundaries are now now not definite, unrelated functionality gets blended collectively either by an accident or simply by making injurious construct decisions (or now now not making any construct decisions in any appreciate). Your code turns into much less and no more cohesive and which capability you’re going to inevitably cease up in anxiety.

Numbers are primitive values, they shouldn’t be coupled to crucial aspects admire phone formatting. Obvious, it’s useful and seems to be to be cute nonetheless it comes with excessive drawbacks. Initially you most definitely can’t preserve along side an increasing number of monkey-patches. There’s a limit. If you reach this limit, you’re going to originate imposing arena-tell functionality in a particular system – here’s where your code already starts losing brotherly love and here’s furthermore how issues changed into much less composable. You’re no longer chaining concepts, you now private a separate abstraction to complete extra heavy work nonetheless it’s now now not phase of the Quantity API, resulting from it could per chance perchance be too worthy.

with monkey-patching system you’re making boundaries inside of your procedure much less definite.

Here’s a easy outcome of striking issues in locations where they don’t belong. Monkey-patches admire to_formatted_s are honestly factual helpers, helpers attached to core courses. They’re easiest wanted in very tell locations; on the other hand, they’re equipped globally attributable to the nature of monkey-patching! Every core object has these concepts irrespective of every little thing. This, in turn, makes it that you just most definitely can recall to mind to reach out for them any place in your code sinister.

! Please furthermore survey my comment here

Naming conflicts

Here could very neatly be the most logical drawback. In the occasion you throw encapsulation out of the window and private that it’s OK to monkey-patch, then it’s straightforward to take into consideration a order where two folks reach up with the an analogous draw title, implement them as a monkey-patch in the an analogous class and now you most definitely can honest private a order.

Let me remind you all over as soon as more: we outmoded to private masses of gem stones transport with monkey-patched core courses, it precipitated somewhat a lot of difficulty, we’ve stopped doing it resulting from it used to be tainted. Easy.

OK so what’s the different?

Ruby! For the admire of Matz, the different is to factual exhaust Ruby. You’ll want to conclude amazing issues with this language with out having to alter core courses. It’s now now not factual about core courses though. There are such a huge amount of libraries on the market that integrate with various libraries by…wonderful, by monkey-patching them. In a style, I survey this which capability (a legacy?) of Rails and the mindset in the help of it. Here’s what we private discovered to complete, but we’re going to conclude higher.

How are you able to conclude composability? You exhaust object composition. It must be as easy as Z.contemporary(x: X.contemporary, y: Y.contemporary). You don’t must write code admire that? I know, me neither. That’s why there are libraries with good abstractions and DSLs. Breeze stare spherical, they exist.

Cease rob a detect at RSpec’s evolution. The absolute top draw it went from "foo".could honest serene eql("foo") to query("foo").to eql("foo"). I don’t think any individual misses the outmoded syntax. I’m certain there are extra examples of such transitions, let me know in case you be aware them.

In the occasion you’re thinking that ActiveSupport’s time helpers can’t get replaced, then rob a detect at time_calc gem. There could be a serious distinction between composable time calculations vs a bunch of time helper concepts attached to integers.

I for sure wanted to give some concrete examples but this is in a position to perchance be too worthy. I’m gonna submit this to accept it out of my head but I’m extra than happy to preserve discussing this field, as you most definitely can survey I’m somewhat eager about it 😉.

In the intervening time, I would admire in case you checked out OSS libraries that me and masses of somewhat a couple of folks private been engaged on for years now. Things will likely be worthy easier for me to factual “blow their private horns” when we’re performed with Hanami 2.0 closing but for now, study out dry-rb – it’s a marvelous instance how libraries would be utilized with out monkey-patching, they’re all composable and unobtrusive, so you most definitely can add them with out problems to an unique code sinister. You’ll want to perchance detect how neatly they play with various libraries!

I’m open to your feedback, questions and concerns (no pun meant!). I maintain I must preserve it up engaged on this article, per chance turn it precise into a sticky web whisper or one thing here. It’s now now not the predominant time when I talk about this subject, and I if truth be told for sure don’t clutch to repeat myself, but I would clutch to private a single useful resource that I could simply point folks to at any time when I catch myself complaining about ActiveSupport on Twitter as soon as more 🤭.

NOW WITH OVER +8500 USERS. folks can Be a part of Knowasiak with out cost. Test in on Knowasiak.com
Read More



“Simplicity, patience, compassion.
These three are your greatest treasures.
Simple in actions and thoughts, you return to the source of being.
Patient with both friends and enemies,
you accord with the way things are.
Compassionate toward yourself,
you reconcile all beings in the world.”
― Lao Tzu, Tao Te Ching

you're currently offline