Hire me only if Quality is your #1 priority. 𝐈 𝐡𝐞𝐥𝐩 𝐬𝐨𝐥𝐯𝐞 𝐩𝐫𝐨𝐛𝐥𝐞𝐦𝐬 𝐥𝐢𝐤𝐞: ✅Complex billing systems (Stripe subscriptions, usage-based pricing). ✅Shopify app limitations and API challenges. ✅SaaS scalability and backend architecture issues. ✅AI/chatbot integrations for automation and user engagement. 𝐂𝐨𝐫𝐞 𝐞𝐱𝐩𝐞𝐫𝐭𝐢𝐬𝐞: 🔹Shopify apps (embedded apps, Admin API, billing flows) 🔹Ruby on Rails & Node.js (SaaS platforms, APIs, microservices) 🔹Stripe (subscriptions, Connect, advanced billing logic) 🔹AI integrations (OpenAI APIs, chatbots, automation workflows using Python) 🔹Cloud & CI/CD (AWS, Docker) 𝐍𝐨𝐭𝐚𝐛𝐥𝐞 𝐏𝐫𝐨𝐣𝐞𝐜𝐭𝐬: ➤Shopify app with Stripe subscription billing + automated workflows ➤SaaS platform with analytics, payments, and AI-based features ➤API backend integrating third-party services and chatbot systems 𝐈𝐟 𝐲𝐨𝐮 𝐰𝐚𝐧𝐭 𝐭𝐨 𝐜𝐨𝐦𝐛𝐢𝐧𝐞 𝐬𝐨𝐥𝐢𝐝 𝐞𝐧𝐠𝐢𝐧𝐞𝐞𝐫𝐢𝐧𝐠 𝐰𝐢𝐭𝐡 𝐦𝐨𝐝𝐞𝐫𝐧 𝐀𝐈 𝐜𝐚𝐩𝐚𝐛𝐢𝐥𝐢𝐭𝐢𝐞𝐬, 𝐈 𝐜𝐚𝐧 𝐡𝐞𝐥𝐩.

As a Full-stack developer, my focus on full stack development has been sharpened by working with a diverse array of clients and technologies, including Ruby on Rails, ASP.NET , React, Vue.js and GraphQL. My tenure has been marked by creating robust web applications and leading innovative projects that drive client satisfaction and operational efficiency. With over seven years of service and a recognized status as top-rated plus on Upwork, has honed my skills in delivering high-quality software solutions. Collaborating closely with teams, I've contributed to the development of applications that meet rigorous standards, leveraging my expertise to strengthen the technical foundations and foster success for our clients and organization.

🟢 Available Now! 🏆 I'm a Top-Rated full-stack developer with 12 years of experience, proficient in a diverse array of technologies, frameworks and AI Workflow automation. 🔥 Also, I would like to join any RUST-involved project as middle developer and minimal rate of $10/hr (I need commercial Rust experience). Currently I'm specializing in Ruby on Rails/Ruby, Python/FastAPI/Flask, JavaScript/TypeScript, Datastar/htmx/stimulus (hypermedia), React/Vue.js, Next.js/Nuxt.js, PostgreSQL, containers and n8n workflows. Proven track record in building and scaling complex web applications using best practices. Strong background in CI/CD, infrastructure management/automation, and cloud deployments. Available for full-time or contract roles. ⚠️️ Choose my specialization in menu and find out more 💼 Over 4000 work hours logged on Upwork and a long list of happy long-term clients. --- 🤝 INDUSTRIES SERVED LONG-TERM - High-load IoT company (realtime microservices) - Healthcare company (medical cards storing and processing) - Virtual mobile operator (realtime microservices) - Logistics company - Car sell service (parsing car sale listings) - Music application backend - Tens of corporate websites (web design, implementation) using various stacks --- 👨‍💻 LANGUAGES - Daily: Ruby, Python, Rust, TypeScript, PL/pgSQL, *sh - Exotic: Elm (underrated gem), Clojure, Haskell, Lua 🐍 PYTHON Frameworks: - FastAPI - FastHTML - Flask Main libs: - asyncpg, AlchemySQL (Core/ORM) - imageio/Moviepy - most likely anything else you'll throw at me 💎 RUBY Web frameworks: - Rack - Sinatra - Hanami - Grape - Ruby on Rails + Hotwired Main libs: - Warden, Pandit, Devise - DRY-* family - PG+query objects, Sequel, ROM, Arel - PORO (Plain Old Ruby Object) - i.e. anything low-level/lightweight ⚡ JAVASCRIPT/TYPESCRIPT Frameworks in order of preference: - Datastar/htmx (hypermedia) - React/Next.js - Vue.js/Nuxt.js - SvelteK/SvelteKit Main libs: - Drizzle ORM - Polka - Express.js - Auth.js - TypeSpec --- 🗄️ DBs/EVENTS - PostgreSQL (favorite!), Elasticsearch, Redis, MySQL, MongoDB, ClickHouse (noob) - Nats.io - just perfect! 🧩 APIs/SERVICES INTEGRATION - OpenAI (ChatGPT), Twilio/Sendgrid, Stripe, Braintree, Pay.nl, Onomondo, tens of them, actually, I can integrate everything - AWS, Azure, GCP, DigitalOcean - Slack, NewRelic, Jenkins - ...tens of them 🐳 DEVOPS - Hashicorp stack (Nomad, Consul, Vault) - my choice if k8n is overkill for the task - Terraform (just love it!) - Ansible (advanced multi-env configurations) - Grafana, Loki, Prometheus - Docker, Ansible, Packer, Capistrano (but prefer ansistrano), etc. 🛠️ SOFTWARE INSTALLATION - n8n (single/cluster mode) - docker - OpenProject - wireguard (VPN) - CloudFlare tunnels (Zero Trust) - ...lots/any of them ☁️ CLOUDS - Google Cloud Platform (almost everything but ML and BigData tools) - AWS - including autoscaling and load balancers of all types - Heroku - DigitalOcean - Render.com, Railway, Heroku, Vercel, Render.com, Neon, Fly.io - literally any --- ⌛ Available 7 days a week, up to 10 hours a day, at any time you need.

Ruby on Rails and React developer. 5+ years shipping SaaS platforms, MVPs, marketplaces, and web applications. PostgreSQL, AI integration, manual QA, and AWS deployment handled in-house. I work with founders, CTOs, and product teams who need one developer to own the full cycle, from architecture and development through testing and production launch. No handoffs. No gaps. Whether you are building a Fintech platform, PropTech tool, HealthTech SaaS, EdTech product, or any web application that needs to be shipped cleanly and maintained reliably, my stack and my process stay the same. Rails handles the backend logic cleanly. React handles the frontend. PostgreSQL holds the data. OpenAI and Claude API add the intelligence. I write the QA plan, run the tests, set up the CI/CD pipeline, and push to production myself. You deal with one person who is accountable for the entire thing. 𝗪𝗵𝗮𝘁 𝗜 𝗯𝘂𝗶𝗹𝗱 SaaS Platform and MVP Development Full stack Rails and React applications built for real production traffic. PostgreSQL schema design, ActiveRecord optimisation, Sidekiq background jobs, Stripe payment integration, role-based authentication, multi-tenant architecture, admin dashboards, and API development. Built to scale from day one. AI Integration OpenAI GPT-4o and Claude API integrated into Rails and React products. RAG pipelines, document chat systems, AI chatbots, semantic search, and n8n workflow automation. Intelligence added to your existing product without a full rebuild. Manual QA Test planning, functional testing, regression testing, edge case coverage, and detailed bug reports with exact reproduction steps. I test the product the way a real user breaks it, before your client does. DevOps and Deployment AWS infrastructure setup, CI/CD pipelines via GitHub Actions, Heroku and Render deployments, environment configuration, PostgreSQL backups, and production monitoring. Launch handled end to end. 𝗣𝗿𝗼𝗱𝘂𝗰𝘁𝗶𝗼𝗻 𝘄𝗼𝗿𝗸 Healthcare SaaS Platform Worked on an AI-enabled clinical pathways and governance SaaS platform serving US health systems. Built workflow-heavy features, real-time collaboration tools, analytics dashboards, and EHR integration using React and Ruby on Rails. Platform impact at one million plus patient lives. Luxury E-Commerce Platform Full stack e-commerce build for a premium jewellery brand. Custom React storefront, product catalogue management, admin CMS, inventory logic, and SEO-optimised Rails backend. Enterprise Corporate Platform Independently owned R&D, development, QA, and full deployment for a corporate AI and digital transformation platform. Complete product lifecycle from architecture to production launch. 𝗪𝗵𝗮𝘁 𝗰𝗹𝗶𝗲𝗻𝘁𝘀 𝘀𝗮𝘆 "Takes real responsibility for the quality of her work. Communicates clearly, thinks through problems instead of rushing solutions." — Upwork client, 5 stars "Deep technical expertise in RAG and document chat systems. Delivered a smart, efficient AI chatbot solution on time." — Upwork client, 5 stars "Solid expertise in backend development with proven experience integrating AI models. Delivers clean, well-documented code." — Upwork client, 5 stars 𝗛𝗼𝘄 𝗜 𝘄𝗼𝗿𝗸 Scope agreed and documented before development begins. Milestone-based delivery with async updates every 48 hours. I flag blockers before they become problems, document everything I build, and stay reachable after launch. If you are building a SaaS platform, launching an MVP, or need AI integrated into an existing Rails or React product, send me a message. I respond within 4 hours.

Experienced Full Stack Developer with over 8+ years of experience in developing, testing, and maintaining scalable web applications using Ruby on Rails and ReactJS. Proficient in building dynamic and responsive applications, managing databases with PostgreSQL and MySQL, and leveraging AWS services such as S3. Adept at working in agile environments and collaborating with cross-functional teams to deliver high-quality software solutions. Technical Skills ● Languages: Ruby, Javascript, WebSockets, Typescript, HTML, CSS ● Frameworks: Ruby on Rails, ReactJS, RemixJS ● Libraries: Redux, JQuery, Bootstrap, Tailwind ● Databases: PostgreSQL, MySQL, SQLite ● Tools: Git, Docker ● Testing: RSpec, Capybara, Shoulda, FactoryGirl, Jest, React Testing Library ● APIs: RESTful APIs, GraphQL ● Integrating with third-party API: Facebook, Twitter, Google, LinkedIn, Sendgrid, Map ● Middleware: Redis/Resque, Sidekiq, Delayed_job ● Other: CI/CD, WebSockets ● Methodologies: Scrum/Agile, TDD, BDD, pair-programming ● Cloud server: EC-2, Digital Ocean, Heroku, Azure Roles I can play : ● Developed and maintained web applications using Ruby on Rails and ReactJS. ● Worked closely across various teams to ensure the timely delivery of top-notch products that meet both project deadlines and client specifications. ● Enhanced application performance and user experience by optimizing SQL queries and background jobs. ● Designed and implemented responsive and visually appealing user interfaces using HTML, CSS, Bootstrap, and other frontend technologies. ● Led a project to refactor legacy code, improving maintainability and reducing technical debt.

I specialize in simplifying and optimising coding practices. I understand the frustration of dealing with tangled codebases, slow performance, and maintenance headaches. By utilizing my expertise in Ruby on Rails and VueJS, I can provide elegant and efficient solutions that enhance productivity and scalability 𝐌𝐘 𝐏𝐑𝐎𝐅𝐄𝐒𝐒𝐈𝐎𝐍𝐀𝐋 𝐀𝐂𝐇𝐈𝐄𝐕𝐄𝐌𝐄𝐍𝐓𝐒 𝐀𝐑𝐄: 📊 Successfully facilitated the growth of the platform user base by over 850,000 users, resulting in a significant expansion of the company's reach and market presence 🔥 Implemented strategies that led to a remarkable 2.7x increase in trial clients and a 2.1x growth in paying clients, contributing to substantial revenue growth and customer acquisition 🚀 Played a pivotal role in securing £2.25 million in seed funding through effective presentations, showcasing the value and potential of the software solution, and convincing investors of its viability and market demand 👏 Streamlined daily operations for the accounting team, resulting in a 31% reduction in the timeframe required to complete their tasks. This optimization allowed for increased productivity, improved efficiency, and cost savings for the company 💰 Successfully led the development and launch of a mission-critical web application using Ruby on Rails, resulting in a 50% reduction in response time and a 30% increase in overall system performance. This achievement not only improved user satisfaction but also optimized server utilization, resulting in cost savings of $50,000 per year for the company 𝐖𝐇𝐀𝐓 𝐌𝐘 𝐂𝐋𝐈𝐄𝐍𝐓𝐒 𝐒𝐀𝐘 𝐀𝐁𝐎𝐔𝐓 𝐌𝐄: ⭐ "Working with Gotoinc was an absolute pleasure. Their expertise in Ruby on Rails was evident throughout the project. Not only did they meet the deadlines, but they also provided valuable insights and recommendations to enhance the overall user experience. Their attention to detail, clean coding practices, and proactive communication made the collaboration seamless. We highly recommend Gotoinc for any web development project" Sam, CTO Healthcare project ⭐ "We had the privilege of partnering with Vadim for our finance software project, and we couldn't be happier with the results. The Gotoinc team’s deep understanding of security measures and best practices helped us build a highly secure and reliable application. They demonstrated exceptional problem-solving skills and worked tirelessly to identify and address any potential vulnerabilities. Their technical proficiency in Ruby on Rails and VueJS, coupled with their dedication to quality, ensured that our project was delivered on time and within budget" Alex, Project Manager FinTech project 🚀 𝗙𝘂𝗹𝗹-𝗦𝘁𝗮𝗰𝗸 𝗪𝗲𝗯 𝗗𝗲𝘃𝗲𝗹𝗼𝗽𝗺𝗲𝗻𝘁: 👉 𝐒𝐤𝐢𝐥𝐥𝐬: Ruby, Ruby on Rails, Sidekiq, RSpec, Capybara, Rubocop, Capistrano, Unicorn, Puma, Ruby gems JavaScript: JavaScript, CoffeeScript, TypeScript, jQuery, VueJs HTML/CSS: HTML5, HAML, ERB, CSS3, SCSS, Bootstrap Databases: PostgreSQL, MySQL, SQLite3, Redis, MongoDB, ElasticSearch Web servers: Nginx, Apache Cloud platforms: Heroku, DigitalOcean, AWS S3 VCS: Git (Github, GitLab, Bitbucket) Development approaches: TDD, BDD, Agile, Scrum 🛠 Project tracking and management software: Jira, Notion, Monday, Trello, PivotalTracker, Gitlab 💬 𝗖𝗼𝗺𝗺𝘂𝗻𝗶𝗰𝗮𝘁𝗶𝗼𝗻 𝗮𝗻𝗱 𝗖𝗼𝗹𝗹𝗮𝗯𝗼𝗿𝗮𝘁𝗶𝗼𝗻 𝗠𝗮𝗻𝗮𝗴𝗲𝗺𝗲𝗻𝘁: 👉 𝐒𝐤𝐢𝐥𝐥𝐬: Effective communication, Collaborative problem-solving, Team leadership, Stakeholder management, Agile project management 🛠 Tools: Jira, Notion, Monday, Trello, PivotalTracker, Gitlab 𝐇𝐎𝐖 𝐓𝐇𝐄 𝐇𝐈𝐑𝐈𝐍𝐆 𝐏𝐑𝐎𝐂𝐄𝐒𝐒 𝐋𝐎𝐎𝐊𝐒 𝐋𝐈𝐊𝐄 There are two options for collaborating with Gotoinc: - Talents-as-a-Service model a dedicated expert(-s) on a subscription basis. Project-Based Collaboration model we deliver a specific scope or solution in a pre-defined timeline/budget. 𝐇𝐨𝐰 𝐭𝐨 𝐬𝐭𝐚𝐫𝐭: 1. Having an intro, where we identify your request 2. Our team identifies specific Talent or Team for your request 3. We deeply research your request and outline unique collaboration terms 4. Gotoinc presents your unique proposal and negotiates it with You 5. We sign a contract 6. We kick off our ongoing collaboration 𝐇𝐢𝐠𝐡𝐥𝐢𝐠𝐡𝐭𝐞𝐝 𝐒𝐤𝐢𝐥𝐥𝐬: Ruby on Rails, JavaScript (VueJs, jQuery), HTML5/CSS3 (SCSS, Bootstrap), Databases (PostgreSQL, MySQL, SQLite3, Redis, MongoDB, ElasticSearch), Web Servers (Nginx, Apache), Cloud Platforms (Heroku, DigitalOcean, AWS S3), Version Control (Git, Github, GitLab, Bitbucket), Development Approaches (TDD, BDD, Agile, Scrum), Project Tracking and Management Last updated: March, 2026

I'm a Full Stack Engineer with over eight years of experience in architecting, scaling, and maintaining complex web applications across diverse industries. I stand out for delivering high-performance and fault-tolerant backend microservices that guarantee integrity and rapid growth for SaaS and enterprise platforms. I'm thrilled to lead projects from their initial architecture to secure, production deployments. What I Offer: • Microservices & API Architecture: Developing and implementing scalable backend microservices using Node.js, NestJS, and Ruby on Rails; developing strong REST and GraphQL APIs. • Performance Engineering: Implemented query optimization, caching mechanisms with Redis ElasticCache, and horizontal scaling strategies while ensuring the responsiveness of the system. • Complex Integrations: Seamlessly integrating important third-party services, such as Stripe, Salesforce, Zuora, Hubspot, Twilio, and Elasticsearch, that drive core business workflows. • DevOps & Cloud: Managed cloud infrastructure on AWS (EC2, RDS, S3) and Heroku. Responsible for overall system architecture and scalability. • Technical leadership, including mentoring of junior team members, code reviews, and technical decision making. Key Architectural Wins (Quantified Impact): • Performance: Improved average API response times by query optimization and implementing different levels of caching on multiple projects. • Architecture: Conceptualized and implemented a scalable, maintainable architecture for a Rails project; improved code organization, reusability, and lowered costs. • Deployment: Implemented applications with the use of serverless EC2, S3 buckets, Redis ElasticCache, and RDS databases for reliable data management and storage. Integrity: Custom authentication implementors and classes for authorization were implemented to devise better error handling and thus secure access to resources.

I build fast, scalable, and user-focused web and mobile applications for startups, small businesses, and enterprises. I’ve worked across Finance, Healthcare, Transportation, and SaaS, delivering solutions that improve performance, automate workflows, and help companies grow. Frontend Development - React.js, Next.js, Angular, Vue.js - HTML5, CSS3, SASS, Tailwind, Material-UI, Bootstrap - TypeScript, Redux, Global State, Component Architecture - Clean, modern, responsive UI/UX Backend Development - Node.js, Express.js, PHP (Laravel, Mason, CGI) - PostgreSQL, MySQL, Sequelize, Prisma - MongoDB, Firebase, Mongoose - REST APIs, GraphQL, Socket.io (real-time apps) ☁️ Cloud & DevOps - AWS & Azure (Certified Solutions Architect) - Docker, CI/CD pipelines - Cloud deployments, scaling, and migrations General Skills - JavaScript (ES6+), TypeScript - API integrations (Stripe, PayPal, OAuth, etc.) - Testing: Jest, Cypress - Clean code, maintainable architecture, best practices

Why Clients Hire Me - Experience building HIPAA-compliant products, including secure data handling, access controls, audit logging, and encryption best practices - Full-stack + AI expertise - Security- and compliance-aware development - Clean, production-ready code - Reliable communication and on-time delivery Backend & APIs - Node.js (MERN), NEST/EXPRESS, Django, Ruby on Rails, PHP - REST & GraphQL APIs - Authentication: JWT, OAuth2, Devise, Firebase Auth - Background jobs & queues (Redis, Sidekiq, Celery) Frontend - React.js, Vue.js, Next.js - Modern, responsive UI with TailwindCSS Databases & Backend Services - PostgreSQL, MySQL, MongoDB, NoSQL - Supabase, Firebase AI & Automation - AI integrations with OpenAI, AWS AI, Google AI - Developer productivity using Cursor, AI copilots, smart prompts - Python automation for data processing and workflows - Cloud, Deployment & Compliance - AWS, Heroku, Vercel, DigitalOcean - Docker, Nginx, CI/CD pipelines, kubernetes

Hi, I’m a Full Stack AI Engineer with strong experience in building AI agents, RAG systems, SaaS platforms, admin dashboards, API integrations, automation workflows, and scalable full-stack web applications. I work across React, Next.js, Node.js, NestJS, Python, Ruby on Rails, MongoDB, PostgreSQL, LangChain, n8n, MCP, and LLM-based systems. My focus is not only writing code, but building production-ready systems that solve real business problems. Recently, I completed AI and full-stack projects including: * AI Developer for Generative & Agentic AI Projects * Built AI workflows using LangChain, RAG, MCP, and agentic AI patterns. The client rated the work 5.0 and mentioned solid AI skills, on-time delivery, and quality code. MERN Admin Dashboard: * Developed a full-stack admin dashboard using React, Node.js, and MongoDB. The work involved clean frontend implementation, backend APIs, dashboard logic, and strong communication throughout the project. Complex Ruby / Full Stack Web App: * Worked for more than a year on a complex legacy web application involving Ruby, JavaScript, CSS, dashboards, recordings, media features, frontend redesign, and feature improvements. Currently, I am also working on: * Multi-agent Genkit framework for agentic backbone setup * Backend development for crypto payments and API integrations * Senior Ruby on Rails development with 3,000+ hours logged * MVP booking platform with functional APIs and product workflows I can help you with: * AI agent development * RAG and LLM integration * LangChain and MCP-based workflows * OpenAI and Claude API integration * n8n automation workflows * SaaS platform development * MVP development * React and Next.js frontend development * Node.js, NestJS, and Express backend development * Ruby on Rails development * API architecture and third-party integrations * Admin dashboards and internal tools * FinTech and payment-related backend systems * DevOps support and deployment workflows What makes me different is that I understand both product delivery and technical execution. I can take a loose idea, convert it into a working plan, build the frontend and backend, integrate AI or automation where needed, and ship clean, maintainable code. If you need someone who can build AI-powered SaaS products, automate business workflows, improve an existing codebase, or develop a full-stack platform from scratch, I can help you move faster with the right technical direction. Keywords: Senior FullStack AI Engineer | MERN developer | AI Automation | AI solutions | Fullstack developer | Node js | React js | MongoDB | Express js | Machine learning | AI chatbots | Natural language processing | Chatbot integration | Data analytics | AI-powered applications | REST APIs | GraphQL | Real-time applications | Socket IO | WebSockets | Cloud deployment | AWS | ECharts | Data visualization | SaaS | AI-based web apps | AI data insights | TypeScript | MongoDB integration | Next js