From 7de0e70d7875b6ca0774c99e5da49b1f8b75c998 Mon Sep 17 00:00:00 2001
From: jbranchaud <jbranchaud@gmail.com>
Date: Fri, 17 Apr 2026 10:51:31 -0400
Subject: [PATCH] Add Define A Set Of Class Methods as a Ruby TIL

---
 README.md                             |  3 +-
 ruby/define-a-set-of-class-methods.md | 46 +++++++++++++++++++++++++++
 2 files changed, 48 insertions(+), 1 deletion(-)
 create mode 100644 ruby/define-a-set-of-class-methods.md

diff --git a/README.md b/README.md
index 7765fb9..8db5b61 100644
--- a/README.md
+++ b/README.md
@@ -10,7 +10,7 @@ working across different projects via [VisualMode](https://www.visualmode.dev/).
 
 For a steady stream of TILs, [sign up for my newsletter](https://visualmode.kit.com/newsletter).
 
-_1776 TILs and counting..._
+_1777 TILs and counting..._
 
 See some of the other learning resources I work on:
 
@@ -1420,6 +1420,7 @@ If you've learned something here, support my efforts writing daily TILs by
 - [Defaulting To Frozen String Literals](ruby/defaulting-to-frozen-string-literals.md)
 - [Define A Custom RSpec Matcher](ruby/define-a-custom-rspec-matcher.md)
 - [Define A Method On A Struct](ruby/define-a-method-on-a-struct.md)
+- [Define A Set Of Class Methods](ruby/define-a-set-of-class-methods.md)
 - [Define Multiline Strings With Heredocs](ruby/define-multiline-strings-with-heredocs.md)
 - [Destructure The First Item From An Array](ruby/destructure-the-first-item-from-an-array.md)
 - [Destructuring Arrays In Blocks](ruby/destructuring-arrays-in-blocks.md)
diff --git a/ruby/define-a-set-of-class-methods.md b/ruby/define-a-set-of-class-methods.md
new file mode 100644
index 0000000..8be3f32
--- /dev/null
+++ b/ruby/define-a-set-of-class-methods.md
@@ -0,0 +1,46 @@
+# Define A Set Of Class Methods
+
+The most common way to define class methods is by defining them directly with
+`self` (the class in the current context) on a method by method basis:
+
+```ruby
+class User
+  def self.find_by(attrs)
+    # lookup logic ...
+  end
+end
+```
+
+If you have a group of class methods you want to define, you can stick them all
+within a `class << self` block which does similarly defines each of them as
+singleton methods of that class (`User` in this case):
+
+```ruby
+class User
+  class << self
+    def find_by_email(email)
+      # lookup logic ...
+    end
+
+    def find_by_last_name(last_name)
+      # lookup logic ...
+    end
+  end
+end
+```
+
+This opens the singleton class of `User` for modification, adding these two new
+methods.
+
+We can see those defined alongside all other direct and inherited class methods:
+
+```ruby
+> User.methods
+=>
+[:find_by_email,
+ :find_by_last_name,
+ :yaml_tag,
+ :allocate,
+ ...
+]
+```