I am a senior full stack software engineer, with an attention to detail and well tested, quality work. I have over a decade of Ruby on Rails experience and even more frontend experience. I excel at diagnosing and fixing bugs. Skills: - Ruby on Rails, RSpec, Sidekiq, Haml, Searchkick, GraphQL Ruby, Devise, Action Policy, Doorkeeper, OmniAuth, Ruby, RBS - HTML, CSS, SCSS, CORS, SVG - REST, GraphQL, OAuth - React, Hotwire, JQuery, Redux, Relay, Material UI - Stripe, S3, Sentry - Redis, PostgreSQL - Accessibility, Security, Internationalization, Performance, Responsive Design, Agile Development - Heroku, Docker, Git, CI, Linux System Administration

Hello, I am a web-development professional with 10+ years of experience building and improving small to big live projects, mostly Ruby on Rails, but have hands on experience with live Elixir and Phoenix projects. My core competency lies in the ability to jump into an existing project, read its code, and start delivering fixes, improvements, and features without delay. As a professional, I want to be a reliable developer who will help you build a good product. I will hear what you need, evaluate it from different perspectives based on my knowledge, then I will give you feedback, we will clarify the task, and I will deliver what we agreed on. I do remember to keep a good balance between development speed, app performance, and maintainability. Which means sane code cleaning, optimization, or testing. Personally I am striving to be reasonable, responsible, and independent, with good emotional health and control. I am interested in a long-term collaboration, preferably part-time(to maintain good work-life balance), comfortable both solo and in a team. Some of my interests: walking, pong, badminton, trekking, mindful sci-fi, chess, engineering, physics, biology, and mind. List of relevant skills and experience Backend: * Ruby * Ruby on Rails * Elixir * Phoenix * LiveView * PostgreSQL, query optimization * REST, Delayed Jobs, caching, CSV import, concurrency handling * Authentication and authorization with Devise, JWT and Pundit * External API's: Facebook and other oAuth, Stripe payments, Currency conversions, Twilio phone calls and SMS, geocoding * Testing with RSpec, Capybara and VCR(TDD and BDD) * Search: Elasticsearch, Solr Frontend: * CSS, SASS, PostCSS, Bootstrap, TailwindCSS * JavaScript, CoffeeScript, ES6, Typescript, Immutable * libraries: Charts.JS, D3, FullCalendar, Google Maps API... * WebPack/Esbuild/Importmaps integration with Rails * Turbo, StimulusJS * ReactJS/Redux framework DevOps: * Git/GitHub * CI and Delivery with CircleCI, GitHub Actions * Hosting with Heroku, Fly.io * AWS S3, R53, CF, B2 * Docker

👋 Hello! I'm Addisu Haile I build high-performance, scalable applications—combining strong backend architecture, modern frontend engineering, and AI-powered automation. My work focuses on clean code, efficiency, and production-ready solutions that help businesses move faster. ⚙️ Core Expertise 🧠 AI & Backend Engineering 📌 FastAPI, Django REST Framework (DRF), ROR, NestJS 📌 AI & LLM Integrations: PydanticAI, OpenAI/LLM APIs, automation workflows 📌 SQLAlchemy & Alembic (async & sync) 📌 Pydantic v2 for data modeling & validation 📌 API Architecture: REST & GraphQL 📌 Databases: PostgreSQL, Supabase, MongoDB 📌 Observability: Logfire, structured logging, tracing 🌐 Frontend Engineering 📌 Next.js | React.js | TypeScript | TailwindCSS | Zustand | RTK Query 📌 Clean admin dashboards, AI interfaces, and frontend layers for backend systems 🛒 E-Commerce & CMS 📌 MedusaJS 📌 PayloadCMS 🛠️ DevOps & Deployment 📌 Dockerized microservices 📌 AWS | Railway | Render | Vercel 📌 CI/CD pipelines and automated deployments 💡 Why Work With Me? ✅ AI-Powered Development — Build smart apps with LLMs, agents, automation ✅ Fast & Scalable Backends — Expert-level FastAPI, DRF, SQLAlchemy, Bullmq ✅ Full-Stack Capabilities — From database schemas to polished UIs ✅ Clean, Production-Ready Code — Strong typing, logging, testing, observability ✅ Reliable Partner — Clear communication, fast delivery, flexible collaboration

I have more than 11 years of experience in RoR programming. Searching for interesting and challenging projects I can work on, to apply my skills and gain great experience. I'm a full-stack developer, which means that I'm strong both on backend and frontend. And I can help to bring your brilliant idea to the world!

Struggling to build scalable, high-performance web applications that drive real business results? My name is Mehmood Ahmed, a Full Stack Developer with 𝟱+ 𝘆𝗲𝗮𝗿𝘀 of experience delivering robust, maintainable solutions that boost user engagement and operational efficiency. Let's transform your vision into a powerful digital reality.
 🚀 𝗛𝗼𝘄 𝗰𝗮𝗻 𝗜 𝗵𝗲𝗹𝗽 𝘆𝗼𝘂 𝐂𝐮𝐬𝐭𝐨𝐦 𝐑𝐮𝐛𝐲 𝐨𝐧 𝐑𝐚𝐢𝐥𝐬 𝐃𝐞𝐯𝐞𝐥𝐨𝐩𝐦𝐞𝐧𝐭 Build scalable, high-performance web applications tailored to your unique business requirements.
 𝗠𝗼𝗱𝗲𝗿𝗻 𝗙𝗿𝗼𝗻𝘁𝗲𝗻𝗱 𝗦𝗼𝗹𝘂𝘁𝗶𝗼𝗻𝘀 (𝗥𝗲𝗮𝗰𝘁 & 𝗡𝗲𝘅𝘁.𝗷𝘀) Create responsive, user-centric interfaces with seamless backend integration for exceptional user experiences.
 𝗔𝗣𝗜 𝗗𝗲𝘃𝗲𝗹𝗼𝗽𝗺𝗲𝗻𝘁 & 𝗜𝗻𝘁𝗲𝗴𝗿𝗮𝘁𝗶𝗼𝗻 𝗗𝗲𝘀𝗶𝗴𝗻 secure, efficient RESTful APIs to connect your services and third-party platforms flawlessly.
 𝗗𝗮𝘁𝗮𝗯𝗮𝘀𝗲 𝗗𝗲𝘀𝗶𝗴𝗻 & 𝗢𝗽𝘁𝗶𝗺𝗶𝘇𝗮𝘁𝗶𝗼𝗻 Craft robust database architectures using PostgreSQL, MySQL, and MongoDB for peak performance.
 𝗖𝗹𝗼𝘂𝗱 𝗗𝗲𝗽𝗹𝗼𝘆𝗺𝗲𝗻𝘁 & 𝗗𝗲𝘃𝗢𝗽𝘀 Deploy and maintain applications on AWS, Heroku, and Digital Ocean with reliable CI/CD pipelines.
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 🏆 𝟱+ 𝗬𝗲𝗮𝗿𝘀 𝗼𝗳 𝗙𝘂𝗹𝗹 𝗦𝘁𝗮𝗰𝗸 𝗘𝘅𝗰𝗲𝗹𝗹𝗲𝗻𝗰𝗲 🚀 Expert in Modern Web Technologies Explore my portfolio below to see successful projects across SaaS, healthcare, e-commerce, and enterprise applications.
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 ➤ 𝗟𝗘𝗧'𝗦 𝗕𝗨𝗜𝗟𝗗 𝗬𝗢𝗨𝗥 𝗡𝗘𝗫𝗧 𝗦𝗨𝗖𝗖𝗘𝗦𝗦 𝗦𝗧𝗢𝗥𝗬 Ready to elevate your web applications with cutting-edge, scalable solutions? Message me on Upwork today for a free consultation and tailored strategy. I typically respond within 6 hours and am eager to accelerate your project success.
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 🛠️ 𝗧𝗢𝗢𝗟𝗦 & 𝗧𝗘𝗖𝗛𝗡𝗢𝗟𝗢𝗚𝗬 𝗟𝗮𝗻𝗴𝘂𝗮𝗴𝗲𝘀 & 𝗙𝗿𝗮𝗺𝗲𝘄𝗼𝗿𝗸𝘀 - Ruby on Rails - JavaScript - React.js - Vue.js - Next.js - Node.js
 𝗙𝗿𝗼𝗻𝘁𝗲𝗻𝗱 𝗧𝗲𝗰𝗵𝗻𝗼𝗹𝗼𝗴𝗶𝗲𝘀 - Hotwire, Turbo, Stimulus - HTML5, CSS3 - jQuery
 𝗗𝗮𝘁𝗮𝗯𝗮𝘀𝗲𝘀 - PostgreSQL - MySQL - MongoDB
 𝗗𝗲𝘃𝗢𝗽𝘀 & 𝗖𝗹𝗼𝘂𝗱 - AWS - Heroku - Digital Ocean - Docker
 𝗔𝗱𝗱𝗶𝘁𝗶𝗼𝗻𝗮𝗹 𝗦𝗸𝗶𝗹𝗹𝘀 - RESTful API Development - Elastic Search - Sidekiq, Redis - RSpec Testing - Git, GitHub, Bitbucket
 𝗥𝘂𝗯𝘆 𝗼𝗻 𝗥𝗮𝗶𝗹𝘀, 𝗙𝘂𝗹𝗹 𝗦𝘁𝗮𝗰𝗸 𝗗𝗲𝘃𝗲𝗹𝗼𝗽𝗺𝗲𝗻𝘁, 𝗥𝗲𝗮𝗰𝘁.𝗷𝘀, 𝗡𝗲𝘅𝘁.𝗷𝘀, 𝗪𝗲𝗯 𝗗𝗲𝘃𝗲𝗹𝗼𝗽𝗺𝗲𝗻𝘁, 𝗝𝗮𝘃𝗮𝗦𝗰𝗿𝗶𝗽𝘁, 𝗔𝗣𝗜 𝗗𝗲𝘃𝗲𝗹𝗼𝗽𝗺𝗲𝗻𝘁, 𝗣𝗼𝘀𝘁𝗴𝗿𝗲𝗦𝗤𝗟, 𝗔𝗪𝗦, 𝗠𝗼𝗱𝗲𝗿𝗻 𝗪𝗲𝗯 𝗔𝗽𝗽𝗹𝗶𝗰𝗮𝘁𝗶𝗼𝗻𝘀

Welcome! With over 6 years of dedicated experience, I bring passion and expertise to web development, specializing in crafting robust applications using the beloved Ruby on Rails stack My track record speaks for itself: 🚀 Previous Achievements: ●Crafted Elearning platform, harnessing the power of over 59 Ruby gems for seamless functionality. ●Engineered a tailored 2-factor authentication system for enhanced security. ●Expertly managed data upload and storage on S3 and B2 buckets, ensuring efficiency and scalability. ●Pioneered Stylinter technology, detecting and rectifying CSS errors with precision. ●Orchestrated custom Linux server cron jobs for vital backup and maintenance tasks. ●Overcame seemingly insurmountable challenges using innovative Ruby gems and Rails patches. ●Navigated complex subscription setups with Stripe API, ensuring optimal user experience. 💼 My Technology Arsenal: ●Ruby on Rails (Versions 4, 5, 6, 7): Your project's powerhouse. ●Rigorous Testing: Employing RSpec, Capybara, and Selenium to uphold quality. ●Diverse Databases: Proficient in PostgresDB, MySQL, and SQLite for data management. ●Server Mastery: Heroku, Digital Ocean, AWS EC2 - your applications are in safe hands. ●CI/CD Implementation: Expertise in Heroku staging apps for seamless integration. ●Payment Gateways: Seamlessly integrate Stripe for secure transactions. ●Seamless Communications: Harnessing Twilio for effective client interaction. ●Social Media Integration: Connecting seamlessly via Google, Facebook, and LinkedIn OAuth. ●Frontend Prowess: HTML5, CSS3, Bootstrap - your interfaces polished to perfection. ●Dynamic Interactivity: Leveraging JavaScript, AJAX, JQuery, and JSON for user engagement. ●Data Mastery: Proficient in web scraping techniques for comprehensive data collection. ●Linux Proficiency: Harnessing BASH scripting for optimized server management. ●Version Control: Proficient in Git and GitHub for seamless collaboration. ●Performance Optimization: Enhancing speed and efficiency through refined algorithms and query optimization. 🔑 My Approach: I recognize the value of Test-Driven Development, ensuring a product that's both comprehensible and sustainable for future developers. Investing more time upfront translates to substantial savings down the line. Let's transform your vision into a reality. Reach out today to discuss how I can contribute to your success.

Highly skilled in Elixir and JavaScript, I bring extensive experience with modern frameworks and libraries such as Elixir/Phoenix, React.js/Redux, Angular/ngrx, Vue.js, TypeScript, Node.js/Express.js, Nest.js and more. A key strength of mine is developing serverless web applications using AWS and integrating various third-party APIs, including Facebook, Twitter, Google, Firebase, Twilio, Payment Gateway, Hubspot, Quickbooks, OAuth, Auth0, and WebRTC. Languages: - Elixir, JavaScript, TypeScript, PHP, Python, Frameworks and Libraries - jQuery - React.js, Redux, Redux-Saga, React Hooks, React Material - Vue.js, Vuetify, Quasar - Node.js, Nest.js, Next.js, Express.js, Socket.io - Phoenix, LiveViews - Angular 4, 6-9, Angular Material - GraphQL - Serverless Databases - MySQL, PostgreSql, MongoDB, Firebase, Elastic Search - Redis Cloud Computing - AWS IAM, Cognito, API Gateway, Lambda, S3, EC2, RDS, DynamoDB, AppSync, Amplify, etc - Google Cloud Platforms Payment Gateways - Stripe, PayPal, Braintree, Authorize.net CI/CD - Circle CI, Travis CI, Bitrise I am looking for challenging projects and startups to help you build something great and hone my skills.

🚀 Ruby on Rails & React SaaS MVP Developer I help startups and founders turn ideas into production-ready SaaS products, CRM systems, dashboards, marketplaces, and business platforms. Over the years, I've worked on web applications involving user management, subscriptions, API integrations, workflow automation, analytics dashboards, and scalable backend systems. My core focus is building MVPs quickly without sacrificing code quality, scalability, or long-term maintainability. What I can help you with: ✅ Ruby on Rails Application Development ✅ SaaS MVP Development ✅ CRM & Admin Dashboard Systems ✅ React.js Frontend Development ✅ REST API Development & Integration ✅ Stripe Subscription & Payment Integrations ✅ PostgreSQL Database Design ✅ Existing Application Improvements & Bug Fixes ✅ Rails Version Upgrades & Legacy Code Refactoring ✅ Performance Optimization & Scalability Improvements Tech Stack: Ruby on Rails React.js Angular JavaScript PostgreSQL Redis Sidekiq REST APIs Docker AWS Heroku GitHub Recent Project Types: • SaaS Platforms • CRM Systems • Learning Management Systems (LMS) • Marketplace Applications • Workflow & Operations Dashboards • Subscription-Based Platforms • Internal Business Tools Why Clients Work With Me: • Strong SaaS and MVP experience • Clear communication and fast response times • Clean, maintainable code • Ability to quickly understand existing codebases • Focus on business goals, not just development tasks If you're building a SaaS product, improving an existing Rails application, or need a reliable long-term development partner, I'd be happy to discuss your project.

I have been working as Full stack since 2009 and I experienced in the frontend, backend and servers maintaining (DevOps). You can find the projects I built in my portfolio. For the last couple of years, I prefer to use Angular for front end development. I also have Ember experience and the Ember concept is much better and closer to rails, but unfortunately, the low community is pretty annoying and sometimes it could take much time to solve unexpected issues. The Angular has a much powerful community and this is a great plus. For the Backend, I use Rails and the gem named Grape if I need to build the API. Someone likes to use RailsApi gem, but I don't like the versioning, Grape is much better at that point for me. Also, the grape request validations are really cool. It seems Grape is a bit quicker then RailsApi. The best quality project, could not be without a ​test, each part should be covered by tests, usually, I use RSpec and capybara. Also, I have experience in javascript testing with Jasmine, and Jasmine is pretty helpful, but sometimes it is really annoying to keep the template fixtures in the actual state, and that is pretty possible to update the view and the jasmine stay green, however, the logic is changed. Based on this the capybara scenario is much better for me. I prefer to build projects from scratch because it allows to fully feel the project and apply the architecture development knowledge.

I am a full-stack developer with over 7 years of experience in Ruby on Rails and React. I have developed, maintained, upgraded, enhanced, and led more than 60 Total Projects in a variety of sizes and industries. Certainly, proactive communication and code quality are the main factors I emphasize for Job Success. I help my customers solve their problems within their limits, bring better website with higher competitiveness and revenue. My PROFICIENCY and EXPERTISE: + Agile Method: Scrum, Kanban. + Knowledge Base: OOP, Design Patterns, MVC, MVP, Microservices. + Application Communication: Restful API, GraphQL, WebSocket. + Web App Framework: Ruby on Rails. + Authentication and Authorization RubyGems: devise, cancancan, rolify, omniauth, jwt, etc. + Other RubyGems: prawn, activeadmin, aasm, acts_as_list, whenever, etc. + Background Jobs: Rails Active Job, Sidekiq, Resque. + Real-time: Rails Action Cable, Firebase, Twilio, etc. + TDD and BDD: Rspec, Capybara, Selenium, etc. + Main Frontend Languages: HTML, CSS, JS. + UX, UI Responsive: Bootstrap, Tailwind, Jquery, etc. + SPA: React, Redux, React Router, etc. + React-based Framework: Next.js - SPA SEO resolution using SSR and SSG. + SQL and No SQL Database: PostgreSQL, MySQL, Redis, etc. + Search Engine: ElasticSearch, Algolia, etc. + Payment Gateway: Stripe, Braintree, etc. + Cloud Computing: Amazon Web Services, Heroku, Digital Ocean, Vercel, etc. + Linux-based: SSH, CronJob, Log Rotation, etc. + Web Server: Nginx, Apache. + Application Server: Puma, Passenger. + Deployment Script: Mina, Capistrano, etc. + CDN: Cloudflare, Cloudfront. + Mail Service: Mailgun, Mailchimp, Sendgrid, etc. + Web Tracking and Analytics: Newrelic, Rollbar, Bugsnag, Sentry, etc. + Other DevOps Skills: Git, Docker, CI/CD, DNS management, HTTPS SSL cert installation, Scaling, Load Balancing, etc.