class User < ApplicationRecord has_many :projects validates :email, presence: true end class User < ApplicationRecord has_many :projects validates :email, presence: true end class User < ApplicationRecord has_many :projects validates :email, presence: true end class User < ApplicationRecord has_many :projects validates :email, presence: true end class User < ApplicationRecord has_many :projects validates :email, presence: true end class User < ApplicationRecord has_many :projects validates :email, presence: true end class User < ApplicationRecord has_many :projects validates :email, presence: true end class User < ApplicationRecord has_many :projects validates :email, presence: true end class User < ApplicationRecord has_many :projects validates :email, presence: true end class User < ApplicationRecord has_many :projects validates :email, presence: true end class User < ApplicationRecord has_many :projects validates :email, presence: true end class User < ApplicationRecord has_many :projects validates :email, presence: true end class User < ApplicationRecord has_many :projects validates :email, presence: true end class User < ApplicationRecord has_many :projects validates :email, presence: true end class User < ApplicationRecord has_many :projects validates :email, presence: true end class User < ApplicationRecord has_many :projects validates :email, presence: true end class User < ApplicationRecord has_many :projects validates :email, presence: true end class User < ApplicationRecord has_many :projects validates :email, presence: true end class User < ApplicationRecord has_many :projects validates :email, presence: true end class User < ApplicationRecord has_many :projects validates :email, presence: true end class User < ApplicationRecord has_many :projects validates :email, presence: true end class User < ApplicationRecord has_many :projects validates :email, presence: true end class User < ApplicationRecord has_many :projects validates :email, presence: true end class User < ApplicationRecord has_many :projects validates :email, presence: true end class User < ApplicationRecord has_many :projects validates :email, presence: true end class User < ApplicationRecord has_many :projects validates :email, presence: true end class User < ApplicationRecord has_many :projects validates :email, presence: true end class User < ApplicationRecord has_many :projects validates :email, presence: true end class User < ApplicationRecord has_many :projects validates :email, presence: true end class User < ApplicationRecord has_many :projects validates :email, presence: true end

Ruby on Rails Developer

Konstantin Raf

Ruby on Rails Expert with 13+ years of experience building robust, scalable web applications

Get in Touch

rails new awesome_app

rails generate model

bundle install

rails db:migrate

My Services

Specialized Ruby on Rails development services to help you build, maintain, and optimize your web applications.

Custom Rails Applications

End-to-end development of custom Ruby on Rails applications tailored to your specific business needs. From concept to deployment, I build scalable and maintainable solutions.

API Development

Design and implementation of robust RESTful and GraphQL APIs using Rails. Create secure, well-documented, and performant APIs that integrate with your existing systems.

Legacy Rails Maintenance

Upgrade and maintain legacy Rails applications. I specialize in version upgrades, security patches, code refactoring, and improving test coverage for existing Rails projects.

Performance Optimization

Identify and resolve performance bottlenecks in your Rails applications. Database optimization, caching strategies, and code profiling to ensure your app runs at peak efficiency.

Rails Consulting

Expert advice on architecture decisions, best practices, and technology choices for your Rails projects. Code reviews, team training, and technical guidance to level up your Rails development.

Test-Driven Development

Implementation of comprehensive testing strategies using RSpec, Capybara, and other testing frameworks. Ensure your Rails application is robust, reliable, and maintainable with proper test coverage.

Portfolio

Check out some of my recent Ruby on Rails projects. Each demonstrates my expertise in building robust, scalable, and maintainable web applications.

Time & Expense Tracking

Upgrade Rails from 6.0 to 7.2, update the React front-end, rebuild AWS deployment pipeline, upgrade Quickbooks integrations

Ruby on Rails

PostgreSQL

React

AWS Elasti Beanstalk

Quickbooks

View the website →

All-in-One Bill Payment

Builld Identity API (authentication), integrate with AWS Cognitot.

Ruby on Rails

PostgreSQL

AWS Cognito

OAuth 2

API development

View the website →

Mental Healthcare Service

Full-stack development, integration of prescription and insurance providers

Ruby on Rails

PostgreSQL

React

EMR

HIPAA

API integration

AWS EC2

View the website →

Services and Product catalog

A website for a design company with a service catalog, dynamic visual features

Ruby on Rails API

PostgreSQL

Bootstrap

JQuery

Capistrano

View the website →

AI-driven text generator

AI generated messages for scraped content, optimized for high load

Ruby on Rails

PostgreSQL

ChatGPT API

Stimulus

Hotwire

Sidekiq

Bootstrap

ActiveAdmin

View the website →

Shopify AI Sales Chatbot

Performance improvement, integration of search tools, optimization of the admin dashboard

Ruby on Rails

PostgreSQL

Shopify

ChatGPT API

Pinecone

Tailwind

View the website →

Survey management for libraries

Upgrade and maintain a survey system for public libraries: dashboards, survey builders, reports, wizards and more

Ruby on Rails

MySQL

Survey Software

API development

View the website →

CMS and user management

Rebuilt the project from scratch, built an advanced admin dashboard, improved data management

Ruby on Rails

PostgreSQL

Requirements analysis

Database design

View the website →

Real Estate Emails parser and organizer

Built the back-end to parse and analyze emails from 10+ real estate portals

Ruby on Rails

PostgreSQL

ActiveAdmin

Sidekiq

Email parsing

Scraping

API development

View the website →

Smart lockers system in the cloud

Helped with scaling up the project, building a bigger team, upgrading the architecture

Ruby on Rails

PostgreSQL

Project Management

Team Building

Code Review

Project architecture

View the website →

Client Testimonials

Here's what clients are saying about my Ruby on Rails development services.

"Konstantin has been an invaluable leader to our team at GrafoAI. He possesses a remarkable depth of technical knowledge and expertise and has consistently delivered high-quality code. Konstantin has a remarkable ability to analyze and solve complex problems, often seeing them before they appear. His ability to meet deadlines and manage tasks efficiently is second to none. K is extremely forward-thinking; always suggesting and implementing innovative ideas and showing his commitment to our mission and goals. He's absolutely invaluable and an all-around great person to work with. I look forward to continuing our partnership with Konstantin well into the future1"

Adam L.

Founder and CEO, grafo.io

"Konstantin worked for us for over 2 years and did an exceptional job in contributing to our Ruby on Rails codebase. He was always willing to dive in deep and was very committed to making our code base better. He has great expertise and would be more than happy to rehire him in the future!"

Aashin N.

VP Engineering, cerebral.com

"Konstantin is extremely knowledgable about ruby on rails and back-end optimization. I recommend him 100%"

Michael M.

Founder, zipchat.ai

"Konstantin is an exceptional RoR Consultant/Dev who deserves high praise for his remarkable contributions to our team in really tough situations. His profound expertise in his guidance for designing complex software systems has been a driving force behind the successful implementation of several critical projects."

Billy W.

Operations Director, elocker.com

"Great working with Konstantin! While there were a few minor hiccups in the project, overall we were glad to complete everything we needed for our platform upgrade."

David A.

Founder, minute7.com

"I'm extremely impressed with Konstantin's depth of knowledge on Ruby and software development in general. He's extremely sharp with software planning and very well organized. I did an initial consultation but plan to bring him in the loop to assist with back-end optimization and project management in the near future. Highly recommended!"

Joel L.

Founder, Lately.com

"Working with Konstantin was a fantastic experience from start to finish. His technical skills are exceptional, and the quality of his work exceeded all expectations. Throughout the project, Konstantin was always available, responsive, and maintained a clear line of communication, which made the entire process incredibly smooth. He consistently delivered on time, and his cooperative nature made him a true partner in this project. I couldn’t be happier with the final result, and I highly recommend Konstantin to anyone who needs a skilled and reliable developer. His dedication and expertise made all the difference, and I’m grateful for his outstanding work for our company."

Brett D.

Head of Marketing, anvilproperty.co.za

"Outstanding developer, skilled, great at communicating, highly recommended 5/5"

Andrew N.

Director of Engineering, Datametric Pty Ltd

"Konstantin is amazing developer, true professional and great human being! Just give him a task, and he will complete it in the most efficient way possible. Transparent communication, top-level programming skills. I can't be more satisfied!"

Roman S.

Product owner, uploadcare.com

"Konstantin has helped us with a variety of projects over the years. Whether it was smaller questions or tasks with a larger scope, he was always very responsive, helpful and professional, and he does great work."

Lizzie J.

Senior Director of Operations, thecultivist.com