You will get Full Stack Developer - React.js, Node.js Ongoing Support / Fixes & Features
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Project details
As a Full Stack Developer, react developer and web developer I provide ongoing support for React, Next.js and Node.js apps - fixes, features, refactors, performance, integrations. 50+ projects, response time under 2 hours, 70% clients long-term.
Working with existing codebase daily. As a backend developer I handle bug fixes, new features, API integrations, database changes, security patches, performance optimization, deployment and CI/CD. Fast turnaround, production-ready - your product keeps shipping without drama.
I work with my team. Stabilise an existing app, not a full rebuild. Trusted developer on call. Ship fast, no hand-holding needed.
Stack: React, Next.js, Node.js, NestJS, TypeScript, PostgreSQL, MongoDB, Stripe, Docker, AWS, Vercel.
Keywords: full stack developer support, full stack developer maintenance, full stack developer React, full stack developer Node.js, full stack developer bug fixes, full stack developer API integration, react developer support, backend developer Node.js, web developer support, saas developer maintenance, senior web developer, full stack developer existing codebase, full stack developer refactoring
Working with existing codebase daily. As a backend developer I handle bug fixes, new features, API integrations, database changes, security patches, performance optimization, deployment and CI/CD. Fast turnaround, production-ready - your product keeps shipping without drama.
I work with my team. Stabilise an existing app, not a full rebuild. Trusted developer on call. Ship fast, no hand-holding needed.
Stack: React, Next.js, Node.js, NestJS, TypeScript, PostgreSQL, MongoDB, Stripe, Docker, AWS, Vercel.
Keywords: full stack developer support, full stack developer maintenance, full stack developer React, full stack developer Node.js, full stack developer bug fixes, full stack developer API integration, react developer support, backend developer Node.js, web developer support, saas developer maintenance, senior web developer, full stack developer existing codebase, full stack developer refactoring
Programming Languages
HTML & CSS, JavaScript, TypeScriptCoding Expertise
Cross Browser & Device Compatibility, Performance Optimization, SecurityWhat's included $6,500
These options are included with the project scope.
$6,500
- Delivery Time 30 days
- Number of Revisions 0
- Source Code
Frequently asked questions
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MW
Mario W.
Mar 27, 2026
Senior Full Stack Developer | Node.js, React.js | SaaS MVP Development & Architecture
Working with Vadym and the team was a positive experience. They supported our SaaS MVP across both architecture and development, communicated clearly, and stayed proactive throughout the project. The work was delivered reliably, and overall the collaboration was smooth and professional
MW
Mario W.
Mar 11, 2026
Integrations between KlickTipp and other tools
Vadym and the team delivered high-quality work on time and were proactive throughout. Communication was clear and reliable. Great experience - we’re happy to continue working together.
MV
Matvey V.
Jul 29, 2025
React Developer
AV
Andrii V.
May 28, 2025
Development of user authorization system + flexible pricing system + refinements
Everything is clear and to the point
JR
James R.
Mar 19, 2025
event platform for assets
Vadym was great to work with—super responsive, easy to communicate with, and really knows his stuff. He handled all the changes I requested quickly and always kept me updated on progress, which made the whole process smooth and stress-free. He delivered exactly what I needed, and I’d definitely work with him again if I need another website built.
About Vadym
Full Stack Developer React Node | Full Stack Node.js React | SaaS + AI
100%
Job Success
Vyshneve, Ukraine - 9:21 am local time
I'm a Full Stack Developer, react developer, front end developer, backend developer, saas developer and mobile app developer. I design, build and scale production-ready web applications end-to-end using React, Next.js, Node.js, NestJS, JavaScript, TypeScript, PostgreSQL and n8n. Recently delivered a major AI SaaS platform with my team - 100K+ users on a single platform alone.
🏆 Why Our Full Stack Development Stands Out
11 years as a Full Stack Developer across B2B SaaS, marketplaces and internal tools
50+ delivered projects, 100+ API endpoints designed and documented
100K+ end users on a single recent platform alone
30+ SPAs and SSR apps shipped to production
Clients reporting up to 7x faster workflows after launch
Legacy system migrations improving response times by up to 6x
Campaign automation improving performance by up to 38%
Average time to working MVP: 4-6 weeks
70% of clients continue working with me long-term
🚀 Full Stack Developer Services
📌 B2B SaaS & Multi-Tenant Platforms
Multi-tenant architecture with RLS, RBAC, SSO and audit logging
Subscription systems with Stripe Connect, payment gateways and billing
Role-based dashboards, admin panels and operations portals
📌 Marketplaces & Booking Platforms
Vendor management, inventory, commissions, Stripe Connect payments
Lead management systems, onboarding flows and automation workflows
Data-heavy platforms with filters, search, reporting tools and CRM integrations
📌 Internal Tools & Custom Web Applications
Customer portals, partner portals and multi-role apps
API-first products and integration layers - 15+ third-party integrations delivered (Stripe, HubSpot, Twilio, SendGrid, Meta, Google)
PostgreSQL schemas, performance tuning. Largest DB: 184M+ records
📌 Cross-Platform Mobile Apps
React Native for iOS & Android - from MVP to production
I'm usually brought in as a full stack developer when you need more than just a website - whether you've outgrown a wordpress developer or need a web developer who can handle the full stack, I cover everything under one roof
📌 AI & Automation (n8n / OpenAI)
n8n workflows connecting existing systems - saved clients 15+ hours/week
OpenAI / LLM integration for summarisation, enrichment and semantic search
CRM automation - lead routing, data sync, campaign performance up to 38%
If AI doesn't add ROI, I keep it simple
🔧 Full Stack Developer Tech Stack & Workflow
React, Next.js, JavaScript, TypeScript, Tailwind CSS | Node.js, NestJS, Express.js, REST APIs, webhooks | PostgreSQL, MySQL, MongoDB, Redis, Supabase | React Native | n8n, OpenAI/LLM, LangChain | Docker, AWS, Vercel, CI/CD
Discovery, architecture, milestone-based delivery (MVP → v1 → iterations). Clean code, full documentation, strong async communication. I work as a full stack developer, full stack web developer, full stack engineer - a hands-on technical lead who takes ownership end-to-end and thinks in systems, not just features.
📊 Recent Results
✅ Enterprise SaaS Platform with AI & RBAC (Orgwise)
• Multi-tenant architecture with RLS, SSO and 5 user roles
• AI-powered process mapping reduced consulting prep time by 60%
• Workflow engine supporting 3 modules, 200+ business processes mapped
✅ AI-Powered Website Builder (Webild)
• Core engineering role, 100,000+ users on the platform
• Real-time AI content generation across the full stack
• Average site generation time: under 90 seconds
✅ High-Load E-commerce Backend Optimization
• Scaled from ~50 req/s to ~300 req/s during promo peaks, zero downtime
• 95th percentile response time reduced from 1.2s to 180ms
✅ Logistics Control Tower Platform
• React + Node.js dashboard with 8 third-party API integrations
• Cut manual data processing by 70%, real-time tracking across 4 providers
🏢 Industries: SaaS, fintech, real estate, e-commerce, logistics, healthcare, management consulting, AI platforms
💡 Data-Backed Results at a Glance
✅ 100K+ users on a single platform
✅ 300 req/s handling during peak traffic with zero downtime
✅ 60% reduction in consulting prep time via AI process mapping
✅ 70% cut in manual data processing
✅ 184M+ records in largest database managed
✅ 15+ hours/week saved through workflow automation
✅ Response time under 2 hours, no hand-holding needed
🚀 Looking for a full stack developer who ships fast and takes real ownership?
📞 Share your context and scope - I'll come back with structure and next steps.
📆 Last Updated: 5/31/26
Steps for completing your project
After purchasing the project, send requirements so Vadym can start the project.
Delivery time starts when Vadym receives requirements from you.
Vadym works on your project following the steps below.
Revisions may occur after the delivery date.
Kickoff & access
You share priorities, links, and your current setup (e.g., project repo invite or hosting details if needed). I confirm scope and the next delivery window
Triage & plan
I review the current state, break work into tasks, estimate, and agree on priorities.