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You will get Full Stack Developer - Tech Lead Architecture, Planning | Node.js/React

Vitalii M.Status: Offline
Vitalii M. Vitalii M.
5.0
Top Rated
Preview imagePreview imagePreview image

Let a pro handle the details

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

Let a pro handle the details

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

Project details

As a Full Stack Developer and technical lead with 11 years and 40+ projects, I provide technical review of your SaaS idea, MVP or existing product. As a react developer and web developer I advise on architecture, not just execute.

We review scope, architecture, risks, integrations and next steps. Works if you need a tech lead view before dev starts, or outside review of an existing system. As a backend developer I think in systems - practical recommendations, better direction, fewer mistakes.

Not a multi-week engagement - a structured first step. Deeper discovery or ongoing advisory can be scoped separately. I work with my team.

Stack: React, Next.js, Node.js, NestJS, TypeScript, PostgreSQL.

Keywords: full stack developer architecture, full stack developer tech lead, full stack developer code review, full stack developer planning, full stack developer SaaS, full stack developer consulting, react developer architecture, backend developer architecture, web developer code review, saas developer architecture, senior web developer, full stack developer React, full stack developer Node.js, full stack developer system design
Programming Languages
HTML & CSS, JavaScript, TypeScript
Coding Expertise
Cross Browser & Device Compatibility, Performance Optimization, Security

What's included $1,600

These options are included with the project scope.

$1,600
  • Delivery Time 7 days
  • Number of Revisions 0
    • Source Code

Frequently asked questions

5.0
4 reviews
100% Complete
(4)
1% Complete
(0)
1% Complete
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ZO

Zack O.
5.00
May 18, 2026
Full Stack Engineer Vitalii and his team have been amazing and very thoughtful. From technical skills to leadership and assistance with our project, everything has been very positive. I highly recommend them for your next project.

LR

Lou R.
5.00
Mar 9, 2026
Frontend Engineer to Build MVP from Scratch (React + TypeScript + Payments)

DJ

David J.
5.00
Jun 29, 2025
MVP Product for Startup in AI x Messaging x Crypto Excellent developer. Responsive, writes quality code, and capable of learning new things quickly.

SM

Seva M.
5.00
Jan 30, 2025
SaaS application development | NodeJS, React, Express, API integration My experience working with Vitalii was very good. Tasks were completed quickly, with a high level of quality. Vitalii was involved in working on many elements of our platform: frontend, backend, browser extension.
I would like to highlight the flexibility with which Vitalii responded to changes in the project. He adapted seamlessly to changes in the scope of work, code style requirements, and process organization, quickly aligning with the evolving dynamics of the team. This is critical for the start-up context.
He was constantly learning and improving their performance.
Vitalii M.Status: Offline

About Vitalii

Vitalii M.Status: Offline
Full Stack Developer | React Node.js | SaaS Developer | Web Developer
100% Job Success
5.0  (4 reviews)
Zaporizhzhya, Ukraine - 4:49 am local time
Full-stack developer (with 10+ years of experience) for SaaS and MVP delivery with AI/LLM features (Node.js/NestJS, React/Next.js, TypeScript, PostgreSQL). 20,000+ users joined the waitlist for a product we built with our team.

I’m a senior full-stack developer building B2B SaaS, multi-tenant products, marketplaces, internal tools, and AI-powered product features. As a full-stack developer, I design backend + frontend together so the platform stays clean, secure, and scalable from MVP → v1 → growth.

🤝 Working model (solo or team)
You work with an engineer from our team on Upwork - no unnecessary bureaucracy.
Need one full-stack developer - we’ll assign the best fit. Need a team - we’ll scale with the right people.

🧩 What I build as a full-stack developer (SaaS, MVP, B2B platforms)

As a full-stack developer, I ship:

* B2B SaaS platforms & multi-tenant products (subscriptions, RBAC, teams)
* MVPs that can grow into v1 without rewrites
* Marketplaces & booking platforms (catalog, vendors, inventory, payments, commissions)
* Internal tools, admin dashboards, back-office systems
* Customer/partner portals with role-based access
* Data-heavy apps (workflows, forms, filtering, reporting)

If you’re hiring a full-stack developer because this is a real platform (users + data + business logic), that’s exactly my lane.

⚙️ Full-stack developer coverage (backend, APIs, data, security)

As a full-stack developer, I cover:

* Architecture: modular monolith by default; microservices only when justified
* APIs: REST, webhooks, clear contracts for frontend/partners
* Integrations: Stripe/Stripe Connect, PayPal, CRMs, email, third-party APIs
* Data: PostgreSQL/MySQL schemas, migrations, indexing, performance tuning
* Security: JWT/sessions, RBAC/permissions, rate limiting, audit logs
* Stabilisation: refactors, tests, regression reduction, reliability improvements

You get a full-stack developer who can build new features and keep the codebase maintainable.

🤖 AI / LLM features (product-grade, not demos)

As a full-stack developer, I implement AI features that actually fit into a SaaS product:

* LLM integration (OpenAI or similar) for summarisation, extraction, classification, routing
* Embeddings + RAG-style retrieval over docs/knowledge bases/internal data
* AI assistants inside the product (support, onboarding, internal ops tools)
* Prompt/version management + safe fallbacks (so the feature doesn’t break the product)

If AI doesn’t add ROI, a good full-stack developer keeps the solution simple and stable.

🛠 Tech stack (focused)

Frontend
* React, Next.js, TypeScript, Tailwind / component systems
Backend
* Node.js, NestJS, Express
Data
* PostgreSQL, MySQL, MongoDB, Redis
AI
* LLM integrations, embeddings, RAG pipelines
Delivery
* Docker, CI/CD, AWS (EC2/ECS/RDS/S3)

🔄 How I work (SaaS/MVP delivery)
Working with me as your full-stack developer:

* Quick discovery (goals, users, constraints, integrations)
* MVP scope → clear milestones → predictable releases
* Clean code, docs, and stable handoff-ready setup
* Long-term support and iteration after launch

✅ When we’re a good match
* You need a full-stack developer for SaaS/MVP work (multi-week product delivery)
* You want ownership across frontend + backend + integrations
* You need AI/LLM features implemented like product features, not a hacky demo
* You care about readable code and long-term maintainability

Last updated: 31 May 2026

Steps for completing your project

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

Delivery time starts when Vitalii receives requirements from you.

Vitalii works on your project following the steps below.

Revisions may occur after the delivery date.

Review project idea, scope, and existing materials

Run the initial technical review and define key recommendations

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