I will build custom ai saas web app with react next js node js python and openai


Level 2
About this gig
Looking for a professional Custom Web Applications, AI chatbot or AI agent application? I help startups, agencies, and businesses build scalable, secure, and high-performance web solutions tailored to their needs.
Services:
Custom Web Applications
SaaS & Startup MVP Development
AI Chatbots & AI Agents
CRM, ERP & Admin Panels
RAG Chatbots & Knowledge Base AI
API Development & Third-Party Integrations
n8n Workflow Automation
Stripe & PayPal Integration
Authentication & Role-Based Access
Real-time Applications
Tech Stack: React.js, Next.js, Node.js, NestJS, TypeScript, Python, OpenAI, Claude, LangChain, n8n, PostgreSQL, MongoDB, Redis, AWS, Docker.
You'll receive clean, maintainable code, responsive UI, scalable architecture, timely delivery, and reliable support. Whether you need an AI-powered solution or a complete SaaS platform, I'm here to bring your idea to life.
Please contact me before placing an order to discuss your project requirements.
Get to know Harinder
Engineering industry leading mobile apps, web apps and AI Solutions
Level 2
- FromIndia
- Member sinceJul 2020
- Avg. response time1 hour
- Last delivery5 days
Languages
Hindi, English
My Portfolio
FAQ
What is RAG, and why does my business need it instead of basic fine-tuning?
RAG (Retrieval-Augmented Generation) securely connects an LLM directly to your private business documents (PDFs, DBs, Notion) via a vector database. Unlike fine-tuning—which alters model weights, is highly expensive, and quickly becomes outdated—RAG dynamically fetches exact, real-time facts from yo
I used an AI-builder (like Lovable or Bolt.new) for my frontend. Can you connect it to a real backend?
Absolutely. Tools like Lovable and Bolt.new are incredible for visual rapid prototyping, but they hit a hard wall when it comes to custom backend architecture, heavy-duty document data ingestion, and complex vector space search. I can step in as your systems architect to build a production-grade, se
How do you guarantee my sensitive corporate data will remain secure and private?
Security is my absolute priority. I design architectures that leverage strict enterprise API data privacy standards (such as OpenAI/Anthropic zero-data-retention APIs) so your queries are never saved or used for future model training. Furthermore, I implement robust environment-variable encryption,
What programming languages and frameworks do you use to build these AI pipelines?
I build high-concurrency, enterprise-ready systems. My core stack includes Python (FastAPI/Django) and Node.js (TypeScript) for robust backend scaling, coupled with LangChain or LlamaIndex for advanced LLM orchestration. For frontend visual dashboards, I utilize React and Next.js. On the database si
What do I need to provide to get started on an order?
o build a successful system blueprint, I will need a clear outline of your target business workflow, the specific LLM model you prefer (e.g., GPT-4o, Claude 3.5 Sonnet), access to sample data formats you want the AI to understand (PDFs, Markdown, database schemas), and details about your current hos
3 reviews for this Gig
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Rating Breakdown
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- Quality of delivery
- Value of delivery
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D darrancemorgan
Repeat Client

United States
Pleasure to work with understands you're goal, very patient, & understanding. He's very detailed & he will not stop until you're satisfied.
Up to $50
Price
3 days
Duration
Helpful?N 
neha2439
Repeat Client

India
Great experience working with Harinder. Excellent work! The documentation was professional, clear, and exactly what I needed. Everything was well-structured and delivered on time. Great communication throughout the project. Highly recommended!
Up to $50
Price
3 days
Duration
Helpful?S sharmabhishrk

India
Harinder delivered excellent work with level of professionalism thats hard to find. His communication was spot on, and he truly understood what was needed .
Up to $50
Price
4 days
Duration
Helpful?
3 reviews for this Gig
| (3) | ||
| (0) | ||
| (0) | ||
| (0) | ||
| (0) |
Rating Breakdown
- Seller communication level
- Quality of delivery
- Value of delivery
Sort By
D darrancemorgan
Repeat Client

United States
Pleasure to work with understands you're goal, very patient, & understanding. He's very detailed & he will not stop until you're satisfied.
Up to $50
Price
3 days
Duration
Helpful?N 
neha2439
Repeat Client

India
Great experience working with Harinder. Excellent work! The documentation was professional, clear, and exactly what I needed. Everything was well-structured and delivered on time. Great communication throughout the project. Highly recommended!
Up to $50
Price
3 days
Duration
Helpful?S sharmabhishrk

India
Harinder delivered excellent work with level of professionalism thats hard to find. His communication was spot on, and he truly understood what was needed .
Up to $50
Price
4 days
Duration
Helpful?

