Muhammad Mohsin R.
Senior Product Engineer | SaaS & AI Integration
I help founders and product teams with SaaS development, AI integration, and legacy modernization—turning ideas and existing systems into reliable production software. I deliver full-stack engineering with Ruby on Rails, Node.js, React, and APIs. Top Rated Plus | 100% Job Success | 15,000+ Upwork hours | 10+ years in software engineering I take ownership beyond implementation: clarifying scope, evaluating trade-offs, shaping software architecture, building the product, and improving it after launch. Because I also build and operate SaaS products, I understand the practical decisions behind the code—what to build first, where AI can create real value, how to control cost and complexity, and how to keep a product maintainable as it grows. I can help with: • AI and LLM integration for SaaS products, web applications, and internal tools • AI assistants, chatbots, model/API integrations, structured outputs, and workflow automation • Full-stack SaaS and MVP development from architecture to production • Ruby on Rails and Node.js backends, React frontends, and third-party API integrations • Legacy application modernization, refactoring, performance, testing, and reliability • Technical audits, product rescue, feasibility reviews, and technical roadmaps Clients have trusted me with long-term, mission-critical applications, complex customer data, third-party systems, and end-to-end SaaS development. I worked with one Upwork client for more than five years, and I contributed to the product and engineering behind a client business that was later sold for $2.25 million. Core technologies: Ruby on Rails, Ruby, Node.js, React, JavaScript, PostgreSQL, Elasticsearch, REST APIs, third-party integrations, and AI/LLM APIs. You can expect clear communication, strong ownership, candid technical advice, and software built for real users and long-term operation—not a disposable demo. Send me a brief description of your product, current stack, and main bottleneck. I’ll tell you whether I’m a good fit and suggest the most practical next step.
Earnings and projects
Last 6 months ÷ 6
Last 6 months: $42k
Billed in all: $414,376$414k
$42k in the last 6 months
Across 58 contracts
Earnings, last 30 days
Skill rankings: Top 1% in Back-End Development
Ranked by MRR among everyone on Upwork with the skill.
- #5ai agent orchestration70 freelancers · 🇵🇰 #1Top 7%🇵🇰#1 of 19
- #27Ruby on Rails1,811 freelancers · 🇵🇰 #5Top 1%🇵🇰#5 of 390
- #38LLM Prompt Engineering2,457 freelancers · 🇵🇰 #9Top 2%🇵🇰#9 of 689
- #38Web Application Development2,030 freelancers · 🇵🇰 #10Top 2%🇵🇰#10 of 618
- #51Software Architecture & Design1,465 freelancers · 🇵🇰 #4Top 3%🇵🇰#4 of 216
- #52Back-End Development4,183 freelancers · 🇵🇰 #13Top 1%🇵🇰#13 of 966
- #55AI Implementation2,383 freelancers · 🇵🇰 #6Top 2%🇵🇰#6 of 416
- #56Software Development2,923 freelancers · 🇵🇰 #5Top 2%🇵🇰#5 of 387