Steve Clarke steveclarke

The Unofficial 37signals/DHH Rails Style Guide

About This Document

This style guide was generated by Claude Code through deep analysis of the Fizzy codebase - 37signals' open-source project management tool.

Why Fizzy matters: While 37signals has long advocated for "vanilla Rails" and opinionated software design, their production codebases (Basecamp, HEY, etc.) have historically been closed source. Fizzy changes that. For the first time, developers can study a real 37signals/DHH-style Rails application - not just blog posts and conference talks, but actual production code with all its patterns, trade-offs, and deliberate omissions.

How this was created: Claude Code analyzed the entire codebase - routes, controllers, models, concerns, views, JavaScript, CSS, tests, and configuration. The goal was to extract not just what patterns are used, but why - inferring philosophy from implementation choices.

Rails 7 new features. Before and After

Add ComparisonValidator
PostgreSQL generated columns
PostgreSQL custom enum types
Add tracking of belongs_to association
association_previously_changed? method
Add invert_where method
Add associated method
Add missing method
Active Record Encryption

Stimulus cheatsheet

Website: https://stimulusjs.org/
GitHub repo: https://github.com/stimulusjs/stimulus
Handbook: https://stimulusjs.org/handbook/introduction
Discourse: https://discourse.stimulusjs.org/

Lifecycle callbacks

initialize: once, when the controller is first instantiated
connect: anytime the controller is connected to the DOM

###rpush - https://github.com/rpush/rpush

Follow the steps in rpush to add the gem to your rails project

####PushNotificationDevice

rails g model PushNotificationDevice device_type:integer:index device_token:string

class CreatePushNotificationDevices < ActiveRecord::Migration

Capybara

save_and_open_page

Matchers

have_button(locator)

	" https://gist.github.com/steveclarke/ba73c6b2e198f14f1b729ad6825c04ca

	" Leader is <space>
	let mapleader = ' '
	nnoremap <Space> <Nop>

	" nobody wants that bell!
	set visualbell

	set incsearch

	# frozen_string_literal: true

	class ApplicationComponent < ViewComponent::Base
	private

	# Reference: https://www.youtube.com/watch?v=YVYRus_2KZM&t=302s
	def fetch_or_fallback(allowed_values, given_value, fallback)
	if allowed_values.include?(given_value)
	given_value
	else

	{% comment %}
	Place at bottom of DOM, before </body>
	{% endcomment %}

	{% comment %}
	Article structured data
	https://developers.google.com/search/docs/data-types/articles
	{% endcomment %}

	{% if template contains 'article' %}

	def original_method(a, b)
	puts "Called with #{a} and #{b}"
	if block_given?
	puts "Calling the block"
	yield
	end
	end

	def wrapper1(*args) # WRONG: doesn't pass the block
	puts "Hi I'm wrapper1"

	source :rubygems

	# We are not loading Active Record, nor Active Resources etc.
	# We can do this in any app by simply replacing the rails gem
	# by the parts we want to use.
	gem "actionpack", "~> 4.0"
	gem "railties", "~> 4.0"
	gem "tzinfo"

	# Let's use thin