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You will get Custom SaaS Web Application | React, Next.js, Node.js Developer

Kirill S.Status: Offline
Kirill S. Kirill S.
5.0
Top Rated
Preview image

Let a pro handle the details

Buy Web Application Programming services from Kirill, priced and ready to go.
Kirill S.Status: Offline
Kirill S. Kirill S.
5.0
Top Rated
Preview image

Let a pro handle the details

Buy Web Application Programming services from Kirill, priced and ready to go.

Project details

As a Senior Full-Stack Developer, I build custom SaaS web applications designed around your business processes, users, and long-term growth.

I work across the entire product lifecycle — from architecture and database design to frontend development, backend APIs, integrations, deployment, and optimization.

With 12+ years of experience and 300+ delivered projects, I bring both technical architecture and hands-on development experience to every project.

TECHNOLOGY STACK:

React.js, Next.js, TypeScript, Node.js, NestJS, Express.js, PostgreSQL, MongoDB, Redis, Stripe, Docker, AWS, Vercel.

PACKAGE INCLUDES:

• Technical architecture
• Frontend application development
• Backend development
• Database architecture
• Authentication and authorization
• SaaS user and organization management
• Core business workflows
• API development
• Third-party integrations
• Testing and quality assurance
• Deployment support
• Technical documentation

I can work with an existing codebase or build your SaaS product from the ground up.
Programming Languages
JavaScript, Java, TypeScript
Coding Expertise
Cross Browser & Device Compatibility, Security, Design

What's included $8,500

These options are included with the project scope.

$8,500
  • Delivery Time 30 days
  • Number of Revisions 1
  • Number of Pages 10
5.0
14 reviews
100% Complete
(14)
1% Complete
(0)
1% Complete
(0)
1% Complete
(0)
1% Complete
(0)

JS

Jonathan S.
5.00
Mar 16, 2026
Salesforce Developer Great Freelancer, Great Team!
I would absolutely recommend working with him. The work quality was excellent, communication was smooth, and the pricing was very fair. He delivered everything very quickly and showed strong Salesforce expertise. I’m looking forward to working together again!

PB

Phil B.
5.00
Feb 24, 2025
Sales Force Developer Dev work in PHP, Salesforce and database in AWS.
Good work and can recommend.

SS

Sam S.
5.00
Sep 24, 2024
Salesforce Development Contract Work

JS

Jonathan S.
5.00
Jan 24, 2024
Salesforce Development support Great Feelancer! Great work and great communication and great consulting . Absulot nothing to complain.
A real expert in Salesforce.

LB

Luc B.
5.00
Oct 11, 2023
Update Heroku project
Kirill S.Status: Offline

About Kirill

Kirill S.Status: Offline
Full Stack Developer Node | Node.js React MERN
100% Job Success
5.0  (14 reviews)
Warsaw, Poland - 12:45 am local time
Hey! I'm Kirill, a Senior Full-Stack Developer with 12+ years of experience building scalable web applications, SaaS platforms, internal business systems, and AI-powered products.

I've successfully delivered 300+ projects for startups, growing businesses, and enterprise clients, taking ownership from architecture and backend development to polished frontend experiences and production deployments.

I enjoy solving complex technical challenges while keeping business goals at the center of every decision.

💼 Core Services

• Full-stack web application development
• React.js, Next.js & TypeScript development
• Node.js, NestJS & Express backend development
• REST & GraphQL API design and implementation
• Database architecture (PostgreSQL, MongoDB, MySQL)
• Authentication, payments, and third-party integrations
• AI integrations with OpenAI, ChatGPT, Claude, Gemini, and custom AI agents
• SaaS product development
• Dashboard and admin panel development
• Performance optimization and application scaling
• Cloud deployment and DevOps
• MVP development for startups
• Long-term product maintenance and feature development

⭐ Why clients work with me

✔️ 12+ years of professional software development
✔️ 300+ successfully delivered projects
✔️ Strong architecture combined with hands-on coding
✔️ Business-oriented approach, not just feature delivery
✔️ Clean, maintainable, scalable code
✔️ Clear communication and reliable execution

🛠 Tech Stack

Frontend
• React.js
• Next.js
• TypeScript
• JavaScript
• Tailwind CSS
• HTML5 & CSS3

Backend
• Node.js
• NestJS
• Express.js
• REST APIs
• GraphQL

Databases
• PostgreSQL
• MongoDB
• MySQL
• Redis

Cloud & DevOps
• AWS
• Docker
• GitHub Actions
• CI/CD
• Vercel
• Heroku

AI & Automation
• OpenAI
• ChatGPT
• Claude
• Gemini
• AI-powered workflows
• Custom AI assistants and automation

Whether you're building a SaaS platform, modern web application, AI-powered product, or need an experienced engineer to accelerate your existing project, I'm ready to help you build scalable software that lasts.

Let's discuss your project

Steps for completing your project

After purchasing the project, send requirements so Kirill can start the project.

Delivery time starts when Kirill receives requirements from you.

Kirill works on your project following the steps below.

Revisions may occur after the delivery date.

Review the Documentation

We will review the documentation in order to provide a detailed development plan, alongside with the estimate.

Review the work, release payment, and leave feedback to Kirill.