The Idea
You change a file. Its neighbors should know. They should adapt, harmonize, evolve. But they just sit there — frozen in their last known state, drifting slowly out of tune.
What if one command could ripple your change outward?
$ koi --poignant 🌊 Pond(my_project, 14 stones) Last touched: 🪨 user.rb touched=14:32:07 Kin: 🪨 authentication.rb, 🪨 profile.rb 🔮 Reflection: 2 files reimagined from 🪨 user.rb
That's Koipond. One stone, thrown by you. Ripples carried by Claude. The pond settles into a new shape.
The Architecture
Koipond is built around four core concepts, each demonstrating Ruby patterns:
A Tour of Ruby, Through Koipond
Every feature of Koipond exists to showcase something about Ruby. Here is the tour.
Refinements — Polite Metamorphosis
Most languages lock their core types. Ruby opens them — and Refinements let you open them politely, scoped to wherever you say using:
module Koipond::StringSwims
refine String do
def ripple!(style: :gentle)
to_stone.throw!(style: style)
end
end
end
# Later, in your code:
using Koipond::StringSwims
"app/models/user.rb".ripple!The String class gains .ripple! only where you ask for it. Everywhere else, strings are still just strings. It is monkey-patching that learned manners.
Struct — Ceremony-Free Objects
When a full class is too much and a Hash is too little:
Stone = Struct.new(:path, :pond, keyword_init: true) do
include Comparable
def <=>(other)
path.heartbeat <=> other.path.heartbeat
end
endOne line gives you initialize, ==, to_a, members, [], each_pair, and more. Then you open the block and add only what's unique. Ruby believes you shouldn't write the same boilerplate twice.
Comparable — Define One Method, Get Six
Include Comparable and define <=>. Ruby gives you <, <=, ==, >=, >, between?, and clamp. For free. Forever.
Stones sort by modification time. The most recently touched file rises to the top. We wrote one method. Ruby wrote the rest.
Enumerable — Define One Method, Get Sixty
The Pond includes Enumerable and defines each. Now the Pond responds to map, select, reduce, sort, min, max, flat_map, group_by, tally, any?, none?, count, take, zip, chunk, each_slice, each_cons... roughly sixty methods, all from one.
This is Ruby's philosophy of generosity. You do the minimum. Ruby multiplies it.
method_missing — The Living Object
When you call a method that doesn't exist, Ruby doesn't just crash. It asks the object: "Do you want to handle this?"
pond = Koipond.pond
pond.user_model # finds user_model.rb
pond.user_model.kin # its relatives
pond.user_model.throw! # reimagine its worldThree words. Reads like English. The Pond intercepts unknown method names, searches its stones, and returns the matching file. The pond feels alive.
TracePoint — The Nature Documentary
TracePoint lets you observe method calls as they happen — live, without modifying any code. Koipond uses it to narrate its own execution:
Koipond.narrate!
🐟 the pond remembers who moved last
🐟 reading the stone's inscription
🐟 searching for family in the water
🐟 a stone arcs through the air
🐟 whispering to Claude across the wire
🐟 ripples spreading outwardMost languages need AOP frameworks for this. Ruby has it built in.
In the Spirit Of
"when you don't create things, you become defined by your tastes rather than ability."— _why the lucky stiff
_why taught us that programming is not just engineering. It is expression. It is play. It is writing a letter to your future self, and maybe to a fox or two along the way.
He gave us Camping (a web framework in 4KB), Shoes (a GUI toolkit for beginners), and Hpricot (an HTML parser that was fast and friendly). He wrote Why's (Poignant) Guide to Ruby, which is the only programming book that has a soundtrack.
Then he disappeared. All his code, gone from the internet. Because maybe the point was never the code. Maybe the point was the feeling you got when you read it.
Koipond is a small attempt to chase that feeling.
Get Started
$ koi --poignant
Or just drop lib/koipond.rb anywhere. It's one file. _why would approve.