This comprehensive guide covers the progression from Junior to Principal Rails Developer, providing detailed explanations and code examples for each skill level. It serves as a roadmap for developers looking to advance their Rails expertise and tackle increasingly complex challenges in web application development.
-
- Advanced ActiveRecord Queries
- Service Objects and Design Patterns
- Performance Optimization Techniques
- Security Best Practices
- Scaling Rails Applications
- Advanced Testing
- Continuous Integration/Continuous Deployment (CI/CD)
- Refactoring and Code Organization
- WebSockets and Action Cable
- Internationalization (i18n) and Localization
-
- System Architecture Design
- Microservices Architecture
- Event-driven Architecture
- Domain-Driven Design (DDD)
- Database Sharding and Replication
- Distributed Systems and Eventual Consistency
- Cloud Infrastructure
- Containerization and Orchestration
- Machine Learning Integration in Rails
- Technical Leadership and Mentoring
Understanding of Model-View-Controller pattern, the role of each component (Models for data and business logic, Views for user interface, Controllers for request handling), and the flow of data and control in a Rails application.
Example:
# app/models/user.rb
class User < ApplicationRecord
validates :email, presence: true, uniqueness: true
end
# app/controllers/users_controller.rb
class UsersController < ApplicationController
def index
@users = User.all
end
end
# app/views/users/index.html.erb
<h1>Users</h1>
<% @users.each do |user| %>
<p><%= user.email %></p>
<% end %>Classes and object-oriented programming concepts, modules for namespacing and mixing in behavior, blocks and yield for creating reusable code segments, and understanding of Ruby's dynamic and duck typing.
Example:
class Animal
def speak
raise NotImplementedError, "Subclass must implement abstract method"
end
end
class Dog < Animal
def speak
"Woof!"
end
end
module Swimmable
def swim
"I'm swimming!"
end
end
class Duck < Animal
include Swimmable
def speak
"Quack!"
end
endORM (Object-Relational Mapping) concept, basic CRUD operations using ActiveRecord methods, and understanding of database tables and model relationships.
Example:
class CreateUsers < ActiveRecord::Migration[6.1]
def change
create_table :users do |t|
t.string :name
t.string :email
t.timestamps
end
end
end
# In Rails console
user = User.create(name: "John Doe", email: "[email protected]")
User.find_by(name: "John Doe")
user.update(email: "[email protected]")
user.destroyUnderstanding of REST (Representational State Transfer) principles, seven standard RESTful actions (index, show, new, create, edit, update, destroy), and implementing RESTful routes in Rails using resources in routes.rb.
Example:
# config/routes.rb
Rails.application.routes.draw do
resources :users
endUsing built-in generators for models, controllers, and views, understanding the files created by each generator, and customizing generator templates for project-specific needs.
Example:
# Terminal commands
rails generate model User name:string email:string
rails generate controller Users index show
Creating and running database migrations, adding, removing, and modifying database columns, and understanding of migration versioning and rollbacks.
Example:
class AddAgeToUsers < ActiveRecord::Migration[6.1]
def change
add_column :users, :age, :integer
end
endImplementing Create, Read, Update, Delete functionality in controllers, building forms for data input and editing, and displaying data in views.
Example:
class UsersController < ApplicationController
def create
@user = User.new(user_params)
if @user.save
redirect_to @user, notice: 'User was successfully created.'
else
render :new
end
end
private
def user_params
params.require(:user).permit(:name, :email)
end
endWriting semantic HTML5, styling with CSS, including flexbox and grid layouts, and understanding of responsive design principles.
Example:
<!-- app/views/layouts/application.html.erb -->
<!DOCTYPE html>
<html>
<head>
<title>My Rails App</title>
<%= csrf_meta_tags %>
<%= csp_meta_tag %>
<%= stylesheet_link_tag 'application', media: 'all', 'data-turbolinks-track': 'reload' %>
</head>
<body>
<%= yield %>
</body>
</html>/* app/assets/stylesheets/application.css */
.container {
display: flex;
flex-direction: column;
max-width: 800px;
margin: 0 auto;
}Basic version control concepts, committing changes, creating branches, and merging, and collaborating with others using pull requests.
Example:
# Terminal commands
git init
git add .
git commit -m "Initial commit"
git branch feature-branch
git checkout feature-branch
git merge feature-branch
Interacting with your Rails application from the command line, testing model associations and queries, and debugging and data manipulation in development.
Example:
# In Rails console
User.count
User.where(age: 18..30).pluck(:name)
User.find(1).update(email: "[email protected]")Implementing complex associations (has_many :through, polymorphic associations), custom validation methods and error messages, callbacks for automating model-related actions, and eager loading to solve N+1 query problems.
Example:
# app/models/user.rb
class User < ApplicationRecord
has_many :posts
has_many :comments, through: :posts
has_one :profile
validates :email, presence: true, uniqueness: true
validates :username, length: { in: 3..20 }
before_save :normalize_email
private
def normalize_email
self.email = email.downcase
end
end
# app/models/post.rb
class Post < ApplicationRecord
belongs_to :user
has_many :comments
# Eager loading example
scope :with_user_and_comments, -> { includes(:user, :comments) }
endImplementing user authentication systems, understanding of sessions and cookies, customizing Devise views and controllers, and implementing alternative authentication strategies (OAuth, JWT).
Example using Devise:
# Gemfile
gem 'devise'
# Terminal
rails generate devise:install
rails generate devise User
# app/models/user.rb
class User < ApplicationRecord
devise :database_authenticatable, :registerable,
:recoverable, :rememberable, :validatable,
:confirmable, :lockable, :timeoutable, :trackable
end
# app/controllers/application_controller.rb
class ApplicationController < ActionController::Base
before_action :authenticate_user!
endDefining and managing user roles and permissions, implementing access control in controllers and views, writing and organizing authorization policies, and handling authorization failures gracefully.
Example using Pundit:
# Gemfile
gem 'pundit'
# app/policies/post_policy.rb
class PostPolicy < ApplicationPolicy
def update?
user.admin? || record.user == user
end
end
# app/controllers/posts_controller.rb
class PostsController < ApplicationController
def update
@post = Post.find(params[:id])
authorize @post
if @post.update(post_params)
redirect_to @post, notice: 'Post updated successfully.'
else
render :edit
end
end
endUnderstanding asset compilation and fingerprinting, managing JavaScript and CSS dependencies, configuring asset precompilation for production, and integrating with modern front-end build tools (Webpack, esbuild).
Example:
# config/initializers/assets.rb
Rails.application.config.assets.version = '1.0'
Rails.application.config.assets.precompile += %w( admin.js admin.css )
# app/assets/config/manifest.js
//= link_tree ../images
//= link_directory ../javascripts .js
//= link_directory ../stylesheets .cssImplementing page, action, and fragment caching, using low-level caching with Rails.cache, configuring and using Redis or Memcached as cache stores, and cache expiration and cache busting techniques.
Example:
# app/views/posts/index.html.erb
<% cache @posts do %>
<% @posts.each do |post| %>
<% cache post do %>
<%= render post %>
<% end %>
<% end %>
<% end %>
# app/controllers/posts_controller.rb
class PostsController < ApplicationController
def index
@posts = Rails.cache.fetch('posts', expires_in: 1.hour) do
Post.all.to_a
end
end
endImplementing asynchronous processing for time-consuming tasks, scheduling recurring jobs, monitoring and managing job queues, and handling job failures and retries.
Example using Sidekiq:
# Gemfile
gem 'sidekiq'
# app/jobs/send_welcome_email_job.rb
class SendWelcomeEmailJob < ApplicationJob
queue_as :default
def perform(user_id)
user = User.find(user_id)
UserMailer.welcome_email(user).deliver_now
end
end
# app/controllers/users_controller.rb
class UsersController < ApplicationController
def create
@user = User.new(user_params)
if @user.save
SendWelcomeEmailJob.perform_later(@user.id)
redirect_to @user, notice: 'User created successfully.'
else
render :new
end
end
endWriting unit tests for models, controllers, and helpers, implementing integration tests for full request/response cycles, using factories (e.g., FactoryBot) for test data generation, and measuring and improving test coverage.
Example:
# spec/models/user_spec.rb
require 'rails_helper'
RSpec.describe User, type: :model do
it "is valid with valid attributes" do
user = build(:user)
expect(user).to be_valid
end
it "is not valid without an email" do
user = build(:user, email: nil)
expect(user).to_not be_valid
end
end
# spec/requests/posts_spec.rb
RSpec.describe "Posts", type: :request do
describe "GET /posts" do
it "returns a successful response" do
get posts_path
expect(response).to have_http_status(:success)
end
end
endWriting unobtrusive JavaScript in Rails applications, using jQuery for DOM manipulation and AJAX requests, implementing client-side form validations, and creating dynamic user interfaces with JavaScript.
Example:
// app/javascript/packs/application.js
import Rails from "@rails/ujs"
import Turbolinks from "turbolinks"
import * as ActiveStorage from "@rails/activestorage"
import "channels"
Rails.start()
Turbolinks.start()
ActiveStorage.start()
$(document).on('turbolinks:load', function() {
$('#new-post-form').on('submit', function(e) {
e.preventDefault();
$.ajax({
url: $(this).attr('action'),
method: 'POST',
data: $(this).serialize(),
success: function(response) {
$('#posts-container').append(response);
$('#new-post-form')[0].reset();
}
});
});
});Designing and implementing RESTful APIs, serializing data with libraries like Active Model Serializers, handling API versioning and documentation, and consuming external APIs using libraries like Faraday or HTTParty.
Example:
# app/controllers/api/v1/posts_controller.rb
module Api
module V1
class PostsController < ApplicationController
def index
@posts = Post.all
render json: @posts
end
end
end
end
# app/serializers/post_serializer.rb
class PostSerializer < ActiveModel::Serializer
attributes :id, :title, :content
belongs_to :user
end
# Consuming external API
require 'httparty'
response = HTTParty.get('https://api.example.com/posts')
posts = JSON.parse(response.body)Identifying and creating appropriate database indexes, writing efficient ActiveRecord queries, using EXPLAIN to analyze query performance, and optimizing database schema for better performance.
Example:
# db/migrate/20230722000000_add_index_to_users_email.rb
class AddIndexToUsersEmail < ActiveRecord::Migration[6.1]
def change
add_index :users, :email
end
end
# Optimized query
users = User.includes(:posts).where(active: true).order(:created_at)
# Using EXPLAIN
User.where(email: '[email protected]').explainWriting complex SQL queries using Arel, optimizing database queries for large datasets, implementing advanced joins and subqueries, and using raw SQL when necessary for performance.
Example:
users_table = User.arel_table
posts_table = Post.arel_table
query = users_table.project(users_table[:id], users_table[:name])
.join(posts_table).on(users_table[:id].eq(posts_table[:user_id]))
.where(posts_table[:published_at].gt(1.month.ago))
.group(users_table[:id])
.having(posts_table[:id].count.gt(5))
User.find_by_sql(query.to_sql)
# Raw SQL for performance
User.find_by_sql(["
SELECT users.*, COUNT(posts.id) as posts_count
FROM users
LEFT JOIN posts ON posts.user_id = users.id
WHERE posts.published_at > ?
GROUP BY users.id
HAVING posts_count > 5
", 1.month.ago])Implementing service objects for complex business logic, applying design patterns (e.g., Decorator, Observer, Strategy), using presenters and view objects for cleaner views, and implementing the Repository pattern for data access.
Example:
# app/services/user_registration_service.rb
class UserRegistrationService
def initialize(user_params)
@user_params = user_params
end
def call
user = User.new(@user_params)
if user.save
send_welcome_email(user)
notify_admin(user)
true
else
false
end
end
private
def send_welcome_email(user)
UserMailer.welcome_email(user).deliver_later
end
def notify_admin(user)
AdminNotifierJob.perform_later(user.id)
end
end
# Decorator Pattern
class UserDecorator < SimpleDelegator
def full_name
"#{first_name} #{last_name}"
end
def member_since
created_at.strftime("%B %Y")
end
endProfiling Rails applications (using tools like rack-mini-profiler), implementing Russian Doll caching, optimizing database queries and indexing, and improving application response time and reducing server load.
Example:
# config/environments/production.rb
Rails.application.configure do
config.cache_classes = true
config.eager_load = true
config.consider_all_requests_local = false
config.action_controller.perform_caching = true
config.public_file_server.enabled = true
config.assets.compile = false
config.active_record.dump_schema_after_migration = false
end
# Russian Doll Caching
# app/views/posts/index.html.erb
<% cache @posts do %>
<% @posts.each do |post| %>
<% cache post do %>
<%= render partial: 'post', locals: { post: post } %>
<% end %>
<% end %>
<% end %>Preventing common vulnerabilities (XSS, CSRF, SQL Injection), implementing proper authentication and authorization, securing APIs with rate limiting and token authentication, and conducting security audits and penetration testing.
Example:
# config/initializers/content_security_policy.rb
Rails.application.config.content_security_policy do |policy|
policy.default_src :self, :https
policy.font_src :self, :https, :data
policy.img_src :self, :https, :data
policy.object_src :none
policy.script_src :self, :https
policy.style_src :self, :https
policy.connect_src :self, :https, 'http://localhost:3035', 'ws://localhost:3035'
end
# app/controllers/application_controller.rb
class ApplicationController < ActionController::Base
protect_from_forgery with: :exception
before_action :set_csrf_cookie
private
def set_csrf_cookie
cookies['CSRF-TOKEN'] = form_authenticity_token
end
endImplementing horizontal and vertical scaling strategies, using load balancers and reverse proxies, optimizing database performance for high traffic, and implementing caching at various levels (CDN, application, database).
Example:
# config/puma.rb
workers ENV.fetch("WEB_CONCURRENCY") { 2 }
threads_count = ENV.fetch("RAILS_MAX_THREADS") { 5 }
threads threads_count, threads_count
preload_app!
rackup DefaultRackup
port ENV.fetch("PORT") { 3000 }
environment ENV.fetch("RAILS_ENV") { "development" }
on_worker_boot do
ActiveRecord::Base.establish_connection
end
# config/initializers/rack_attack.rb
class Rack::Attack
throttle('req/ip', limit: 300, period: 5.minutes) do |req|
req.ip
end
endWriting comprehensive test suites with RSpec, implementing behavior-driven development (BDD) with Cucumber, using mocks, stubs, and doubles for isolated unit testing, and implementing continuous integration and automated testing pipelines.
Example:
# spec/system/user_signs_up_spec.rb
require 'rails_helper'
RSpec.describe 'User signs up', type: :system do
before do
driven_by(:selenium_chrome_headless)
end
it 'allows a user to sign up' do
visit new_user_registration_path
fill_in 'Email', with: '[email protected]'
fill_in 'Password', with: 'password'
fill_in 'Password confirmation', with: 'password'
click_button 'Sign up'
expect(page).to have_content 'Welcome! You have signed up successfully.'
expect(User.last.email).to eq '[email protected]'
end
end
# spec/support/capybara.rb
Capybara.register_driver :selenium_chrome_headless do |app|
options = Selenium::WebDriver::Chrome::Options.new
options.add_argument('--headless')
options.add_argument('--disable-gpu')
options.add_argument('--no-sandbox')
Capybara::Selenium::Driver.new(app, browser: :chrome, options: options)
endSetting up CI/CD pipelines (e.g., Jenkins, GitLab CI, GitHub Actions), implementing automated testing and code quality checks, managing different deployment environments (staging, production), and implementing zero-downtime deployments.
Example:
# .gitlab-ci.yml
stages:
- test
- deploy
rspec:
stage: test
script:
- bundle install
- bundle exec rspec
rubocop:
stage: test
script:
- bundle exec rubocop
deploy_production:
stage: deploy
script:
- bundle exec cap production deploy
only:
- mainIdentifying and refactoring code smells, applying SOLID principles to Rails applications, organizing large Rails applications (e.g., using engines), and implementing domain-driven design concepts in Rails.
Example:
# Before refactoring
class User < ApplicationRecord
def full_name
"#{first_name} #{last_name}"
end
def send_welcome_email
UserMailer.welcome_email(self).deliver_now
end
def calculate_age
((Time.zone.now - birthdate.to_time) / 1.year.seconds).floor
end
end
# After refactoring
class User < ApplicationRecord
include NameConcern
include EmailConcern
include AgeConcern
end
module NameConcern
extend ActiveSupport::Concern
def full_name
"#{first_name} #{last_name}"
end
end
module EmailConcern
extend ActiveSupport::Concern
def send_welcome_email
UserMailer.welcome_email(self).deliver_later
end
end
module AgeConcern
extend ActiveSupport::Concern
def calculate_age
((Time.zone.now - birthdate.to_time) / 1.year.seconds).floor
end
endImplementing real-time features with Action Cable, scaling WebSocket connections, integrating WebSockets with background jobs, and securing WebSocket connections.
Example:
# app/channels/chat_channel.rb
class ChatChannel < ApplicationCable::Channel
def subscribed
stream_from "chat_#{params[:room_id]}"
end
def receive(data)
ActionCable.server.broadcast("chat_#{params[:room_id]}", data)
end
end
# app/javascript/channels/chat_channel.js
import consumer from "./consumer"
consumer.subscriptions.create({ channel: "ChatChannel", room_id: 1 }, {
received(data) {
this.appendLine(data)
},
appendLine(data) {
const html = this.createLine(data)
const element = document.querySelector("[data-chat-room='1']")
element.insertAdjacentHTML("beforeend", html)
},
createLine(data) {
return `
<div class="message">
<span class="message__user">${data["user"]}: </span>
<span class="message__text">${data["message"]}</span>
</div>
`
}
})Implementing multi-language support in Rails applications, managing translations and locales, handling date, time, and number formatting for different locales, and implementing right-to-left (RTL) support for applicable languages.
Example:
# config/application.rb
module YourApp
class Application < Rails::Application
config.i18n.load_path += Dir[Rails.root.join('config', 'locales', '**', '*.{rb,yml}')]
config.i18n.available_locales = [:en, :es, :fr]
config.i18n.default_locale = :en
end
end
# config/locales/en.yml
en:
hello: "Hello"
welcome_message: "Welcome to our site, %{name}!"
date:
formats:
default: "%Y-%m-%d"
long: "%B %d, %Y"
# app/controllers/application_controller.rb
class ApplicationController < ActionController::Base
before_action :set_locale
def set_locale
I18n.locale = params[:locale] || I18n.default_locale
end
end
# app/views/welcome/index.html.erb
<h1><%= t('hello') %></h1>
<p><%= t('welcome_message', name: current_user.name) %></p>
<p><%= l(Date.today, format: :long) %></p>Designing scalable and maintainable system architectures, making strategic technology choices for large-scale applications, balancing trade-offs between different architectural approaches, and implementing patterns like CQRS (Command Query Responsibility Segregation) and Event Sourcing.
Example of a modular monolith architecture:
# config/application.rb
module MyLargeApp
class Application < Rails::Application
config.autoload_paths += %W(#{config.root}/app/services)
config.autoload_paths += Dir["#{config.root}/app/modules/**/"]
end
end
# app/modules/user_management/app/models/user_management/user.rb
module UserManagement
class User < ApplicationRecord
# User model implementation
end
end
# app/modules/billing/app/services/billing/invoice_service.rb
module Billing
class InvoiceService
def generate_invoice(user)
# Invoice generation logic
end
end
endDesigning and implementing microservices-based systems, managing inter-service communication (e.g., REST, gRPC, message queues), implementing service discovery and API gateways, and ensuring data consistency across microservices.
Example of a service discovery setup using Consul:
# Gemfile
gem 'diplomat'
# config/initializers/consul.rb
Diplomat.configure do |config|
config.url = 'http://localhost:8500'
end
# app/services/user_service.rb
class UserService
def fetch_user(id)
user_service_url = Diplomat::Service.get('user-service')
response = HTTP.get("#{user_service_url}/users/#{id}")
JSON.parse(response.body)
end
endDesigning systems using event-driven principles, implementing message brokers (e.g., RabbitMQ, Apache Kafka), ensuring event consistency and handling failures, and implementing event sourcing for complex business domains.
Example using Apache Kafka with ruby-kafka gem:
# Gemfile
gem 'ruby-kafka'
# config/initializers/kafka_producer.rb
KAFKA_PRODUCER = Kafka.new(seed_brokers: ['localhost:9092'])
# app/services/order_service.rb
class OrderService
def create_order(user_id, items)
order = Order.create!(user_id: user_id, items: items)
KAFKA_PRODUCER.deliver_message({ order_id: order.id }.to_json, topic: 'orders')
order
end
end
# app/workers/order_processor.rb
class OrderProcessor
def process
consumer = KAFKA_PRODUCER.consumer(group_id: 'order_processors')
consumer.subscribe('orders')
consumer.each_message do |message|
order_data = JSON.parse(message.value)
process_order(order_data['order_id'])
end
end
private
def process_order(order_id)
# Order processing logic
end
endApplying DDD principles to complex Rails applications, defining bounded contexts and aggregates, implementing ubiquitous language in code and communication, and designing rich domain models and separating domain logic from infrastructure.
Example of a bounded context for an e-commerce application:
# app/bounded_contexts/catalog/app/models/catalog/product.rb
module Catalog
class Product < ApplicationRecord
# Product model specific to the Catalog context
end
end
# app/bounded_contexts/ordering/app/models/ordering/order.rb
module Ordering
class Order < ApplicationRecord
# Order model specific to the Ordering context
end
end
# app/bounded_contexts/shipping/app/services/shipping/shipment_service.rb
module Shipping
class ShipmentService
def create_shipment(order)
# Shipment creation logic
end
end
endImplementing database sharding for horizontal scalability, setting up and managing database replication, ensuring data consistency across shards and replicas, and optimizing query routing and execution in sharded environments.
Example using Octopus gem for database sharding:
# Gemfile
gem 'ar-octopus'
# config/shards.yml
octopus:
environments:
- production
production:
shards:
shard1:
adapter: postgresql
host: shard1.example.com
database
database: myapp_shard1
shard2:
adapter: postgresql
host: shard2.example.com
database: myapp_shard2
# app/models/user.rb
class User < ApplicationRecord
octopus_establish_connection(:production)
use_octopus_for_sharding
def self.shard_for_user(user_id)
"shard#{user_id % 2 + 1}"
end
end
# Usage
User.using(User.shard_for_user(user_id)).find(user_id)Designing systems that maintain consistency in distributed environments, implementing conflict resolution strategies, understanding and applying CAP theorem principles, and implementing distributed caching and state management.
Example of implementing a distributed cache with Redis:
# Gemfile
gem 'redis'
gem 'connection_pool'
# config/initializers/redis.rb
REDIS = ConnectionPool.new(size: 5, timeout: 5) { Redis.new(url: ENV['REDIS_URL']) }
# app/models/concerns/cacheable.rb
module Cacheable
extend ActiveSupport::Concern
class_methods do
def fetch_with_cache(id)
REDIS.with do |conn|
cached = conn.get("#{self.name.downcase}:#{id}")
return JSON.parse(cached) if cached
record = find(id)
conn.set("#{self.name.downcase}:#{id}", record.to_json)
record
end
end
end
end
# Usage
class Product < ApplicationRecord
include Cacheable
end
product = Product.fetch_with_cache(1)Architecting cloud-native Rails applications, implementing auto-scaling and load balancing, designing for high availability and disaster recovery, and optimizing cloud resource usage and costs.
Example of setting up AWS resources using Terraform:
# main.tf
provider "aws" {
region = "us-west-2"
}
resource "aws_instance" "web" {
ami = "ami-0c55b159cbfafe1f0"
instance_type = "t2.micro"
tags = {
Name = "WebServer"
}
}
resource "aws_s3_bucket" "app_assets" {
bucket = "my-app-assets"
acl = "private"
versioning {
enabled = true
}
}Containerizing Rails applications and services, designing and managing Kubernetes clusters, implementing CI/CD pipelines for containerized applications, and ensuring security and monitoring in container environments.
Example Dockerfile for a Rails application:
# Dockerfile
FROM ruby:3.0.0
RUN apt-get update -qq && apt-get install -y nodejs postgresql-client
WORKDIR /myapp
COPY Gemfile /myapp/Gemfile
COPY Gemfile.lock /myapp/Gemfile.lock
RUN bundle install
COPY . /myapp
EXPOSE 3000
CMD ["rails", "server", "-b", "0.0.0.0"]Example Kubernetes deployment:
# kubernetes/deployment.yml
apiVersion: apps/v1
kind: Deployment
metadata:
name: myapp
spec:
replicas: 3
selector:
matchLabels:
app: myapp
template:
metadata:
labels:
app: myapp
spec:
containers:
- name: myapp
image: myapp:latest
ports:
- containerPort: 3000Integrating machine learning models into Rails applications, implementing real-time prediction services, managing and updating ML models in production, and ensuring scalability and performance of ML-powered features.
Example of integrating a machine learning model using Ruby's Torch.rb:
# Gemfile
gem 'torch-rb'
# app/services/product_recommender.rb
class ProductRecommender
def initialize
@model = Torch.load('lib/models/product_recommender.pt')
@model.eval
end
def recommend_products(user_id)
user_tensor = Torch.tensor([[user_id]])
output = @model.forward(user_tensor)
product_ids = output.argmax(dim: 1).to_a
Product.where(id: product_ids)
end
end
# Usage
recommender = ProductRecommender.new
recommended_products = recommender.recommend_products(current_user.id)Providing technical vision and strategy for large projects or organizations, mentoring and developing senior developers, conducting architecture reviews and setting coding standards, balancing technical debt with feature development, and communicating complex technical concepts to non-technical stakeholders.
Example of a code review checklist:
CODE_REVIEW_CHECKLIST = [
'Does the code follow our style guide?',
'Are there appropriate tests for the new functionality?',
'Is the code DRY (Don't Repeat Yourself)?',
'Are edge cases handled appropriately?',
'Is there proper error handling and logging?',
'Is the code performant and scalable?',
'Are there any potential security issues?',
'Is the documentation clear and up-to-date?'
]Example of a technical decision document template:
TECH_DECISION_TEMPLATE = <<~TEMPLATE
# Technical Decision: [Title]
## Context
[Describe the current situation and why a decision is needed]
## Options Considered
1. [Option 1]
2. [Option 2]
3. [Option 3]
## Decision
[State the chosen option and rationale]
## Consequences
[Describe the impact of this decision, both positive and negative]
## Action Items
[List any follow-up tasks or considerations]
TEMPLATE
# Usage in a Rails application
class TechnicalDecisionController < ApplicationController
def new
@decision_template = TECH_DECISION_TEMPLATE
end
def create
# Logic to save the technical decision document
end
end