diff --git a/ruby/day_23.rb b/ruby/day_23.rb
new file mode 100644
index 0000000..9330ebf
--- /dev/null
+++ b/ruby/day_23.rb
@@ -0,0 +1,86 @@
+class Computer < Struct.new(:instructions)
+  INSTRUCTIONS = {
+    hlf: ->(c,r) { c.registers[r] /= 2; c.pc += 1 },
+    tpl: ->(c,r) { c.registers[r] *= 3; c.pc += 1 },
+    inc: ->(c,r) { c.registers[r] += 1; c.pc += 1 },
+    jmp: ->(c,o) { c.pc += o.to_i },
+    jie: ->(c,r,o) { c.pc += (c.registers[r].even?) ? o.to_i : 1 },
+    jio: ->(c,r,o) { c.pc += (c.registers[r] == 1) ? o.to_i : 1 },
+  }
+
+  attr_reader :registers
+  attr_accessor :pc
+
+  def initialize(*)
+    super
+
+    @registers = Hash.new(0)
+    @pc = 0
+  end
+
+  def run!
+    loop do
+      instruction, *args = self.instructions[self.pc]
+      break if instruction.nil?
+
+      INSTRUCTIONS[instruction.to_sym].call(self, *args)
+    end
+  end
+end
+
+instructions = DATA.read.split("\n").map {|line| line.split(/,? /) }
+
+c = Computer.new(instructions)
+c.run!
+p c.registers
+
+__END__
+jio a, +19
+inc a
+tpl a
+inc a
+tpl a
+inc a
+tpl a
+tpl a
+inc a
+inc a
+tpl a
+tpl a
+inc a
+inc a
+tpl a
+inc a
+inc a
+tpl a
+jmp +23
+tpl a
+tpl a
+inc a
+inc a
+tpl a
+inc a
+inc a
+tpl a
+inc a
+tpl a
+inc a
+tpl a
+inc a
+tpl a
+inc a
+inc a
+tpl a
+inc a
+inc a
+tpl a
+tpl a
+inc a
+jio a, +8
+inc b
+jie a, +4
+tpl a
+inc a
+jmp +2
+hlf a
+jmp -7