I build SaaS products & AI systems for founders, backed by a full team using Custom Code & Agentic AI.
Senior engineer with 10+ years designing scalable SaaS architectures and intelligent LLM workflows. React, Next.js, Node.js & PostgreSQL, with AI features when your product needs them.
Modern Battle-Tested Stack
Four specialized offers. Shipped with precision.
Fixed milestones, modern tech stack, and zero unnecessary bureaucracy.
SaaS MVP Development
From wireframe idea to market-ready product in 3 to 4 weeks.
End-to-end full stack execution for startup founders. Includes secure authentication, Stripe/Paddle subscription billing, multi-tenant databases, transactional emails, and an intuitive customer dashboard.
- Complete Next.js App Router & TypeScript frontend
- PostgreSQL schema with Prisma or Drizzle ORM
- NextAuth / Clerk authentication (OAuth, magic links, MFA)
Full Stack Website Development
High-performance, scalable web platforms and applications built for conversion and speed.
Custom full-stack web applications and modern corporate platforms tailored to your business needs. Featuring responsive mobile-first UI, robust backend APIs, role-based access, fast database queries, and seamless CMS integration.
- Custom Next.js & React full-stack web architecture
- High-performance database modeling (PostgreSQL / MongoDB)
- Role-based access control (RBAC) and user management
AI Integration & Workflows
Embed smart LLM copilots, RAG semantic search, and document AI.
Modernize your software with practical AI features that drive actual customer retention. We build reliable prompt architectures, pgvector search pipelines, automated data extraction, and conversational agents.
- OpenAI & Google Gemini API integrations
- RAG (Retrieval-Augmented Generation) with pgvector / Pinecone
- Streaming response generation with markdown rendering
API, Database & Payment Integration
Resilient transactional infrastructure, database modeling, and zero dropped webhooks.
Connect your software to any third-party ecosystem with robust database architecture. We specialize in complex payment gateways, marketplace split-payments (Stripe Connect), secure schema design, background queues, and reliable webhook ingestion.
- Stripe Connect, PayPal & payment gateway integrations
- Relational & NoSQL database modeling (PostgreSQL, MySQL, Redis)
- Third-party API integrations (Twilio, HubSpot, OpenAI, CRM)
Featured Case Studies & Work
Real SaaS applications built for founders, shipped on time, and measured by tangible business results.
LearnPulse SaaS — Adaptive AI Learning & Exam Engine
The founder had a high-demand curriculum but was losing 70% of potential students due to an outdated manual LMS that crashed during live examinations and lacked automated assignment grading.
PropFlow CRM — Enterprise Real Estate Pipeline & Deal Engine
A regional real estate brokerage with 45 agents was managing $60M in active pipeline across brittle spreadsheets, losing buyer leads and missing critical closing deadlines.
DataSense AI — Executive Analytics & Automated Copilot
B2B SaaS leadership was drowning in disparate SQL queries, Google Sheets, and Stripe revenue logs to compile weekly board reports and cohort analyses.
How we take your idea to production
Four clear steps with fixed milestones and zero guesswork. You always know what is being built, when it will ship, and what it costs.
Discovery Call & Technical Scoping
We spend 30 minutes clarifying your product goals, technical constraints, target users, and key features. You receive a crisp scope breakdown with no fluff.
Fixed-Milestone Architecture Plan
Before writing a line of code, we agree on a transparent roadmap with fixed milestone pricing and hard delivery dates. No surprise invoices or open-ended hourly creep.
Rapid Build & Weekly Live Demos
I build the core architecture while our team supports UI polish and test coverage. You get weekly video walkthroughs and staging links to test real working software.
Production Launch & 30-Day Warranty
We handle deployment to your cloud environment, configure domain DNS, set up monitoring, hand over 100% intellectual property, and back it with 30 days of post-launch bug support.
Client recommendation
Verified feedback and ratings from founders, product leaders, and engineering teams who hired Muhammad Monir Hossain on Upwork.
“Excellent developer! Built the Fitness SaaS with a clean structure and smooth, modern UI. Everything works as required.”
“It was a pleasure dealing with this developer. On schedule, a responsive, safe, and quick e-commerce platform was delivered. Greatly recommended!”
“Top-tier Web Designer and developer. Built a premium luxury e-commerce store with high attention to conversion, seamless animations, and flawless responsiveness.”
“Great communication, fast delivery, and very professional approach. The website for our accounting firm was delivered on schedule with high attention to detail and clean code.”
“Delivered exactly what was promised on schedule. Great technical skills and reliable full-stack execution across the entire international web platform.”
“Smooth milestone-based delivery across all phases from prototype to discovery and implementation. Highly competent full-stack engineer who understands B2B workflows.”
Senior engineering lead, backed by a dedicated studio team.
You work directly with me on system design, architecture, and core features. When your project requires custom Figma UI designs, intensive database optimizations, or automated QA testing, our studio team at Softvence Agency steps in so we ship on time without cutting corners.
Ready to turn your product idea into a production SaaS?
Work with me directly through Upwork with verified escrow protection, fixed-price milestone delivery, and rapid communication.