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Valentyn S.Status: Offline
Valentyn S. Valentyn S.
5.0
Top Rated
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Let a pro handle the details

Buy Custom Website Programming services from Valentyn, priced and ready to go.
Valentyn S.Status: Offline
Valentyn S. Valentyn S.
5.0
Top Rated
Preview imagePreview imagePreview imagePreview imagePreview imagePreview imagePreview imagePreview image

Let a pro handle the details

Buy Custom Website Programming services from Valentyn, priced and ready to go.

Project details

We bring you a business solution, not just a web application development, but a full-cycle IT business consultancy and our honest opinion regarding your business.

React Developer, React Development Frontend developer React developer Web app frontend developer React, React Developer, React Development Frontend developer React developer Web app frontend developer ReactReact Developer, React Development Frontend developer React developer Web app frontend developer ReactReact Developer, React Development Frontend developer React developer Web app frontend developer ReactReact Developer, React Development Frontend developer React developer Web app frontend developer ReactReact Developer, React Development Frontend developer React developer Web app frontend developer ReactReact Developer, React Development Frontend developer React developer Web app frontend developer ReactReact Developer, React Development Frontend developer React developer Web app frontend developer ReactReact Developer, React Development Frontend developer React developer Web app frontend developer ReactReact Developer, React Development Frontend developer React developer Web app frontend developer Developer
Programming Languages
JavaScript, TypeScript

What's included $8,000

These options are included with the project scope.

$8,000
  • Delivery Time 50 days
  • Number of Revisions 5
  • Number of Pages 0
    • Design Customization
    • Responsive Design
    • Source Code
5.0
23 reviews
100% Complete
(23)
1% Complete
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1% Complete
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1% Complete
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1% Complete
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AR

Aidan R.
5.00
Mar 3, 2026
UI/UX Redesign + Frontend Refactor + Supabase Fixes/Refractor for AI Voice Agent SaaS Platform

DB

David B.
5.00
Dec 19, 2025
UX/UI for SaaS; Expert in Onboarding User Flow It was a pleasure working together. Valentyn is a professional with the right skills for the job, clear communication, and the dedication to deliver. Thank you.

MP

Mitchell P.
5.00
Sep 12, 2025
React Front End Developer

MR

Max R.
5.00
Aug 1, 2025
Product manager/marketer for a small SaaS startup Valentin did a great job helping me connect with our users, launch regular interviews, set up a systematic backlog, and run daily stand-ups with the developer.

As a result, our processes became much more transparent and effective, with clear priorities based on feedback from current and future users.

I definitely recommend Valentin for projects that involve product ownership, collaboration with developers, and design work.

AK

Andrii K.
5.00
Jul 29, 2025
60 minute consultation Had a 1-hour consultation with Valentin - he was well prepared, reviewed all project materials in advance, and provided valuable insights on cloud architecture and microservices. He clearly explained the pros and cons of different approaches and helped identify potential bottlenecks. The session was efficient and informative. I plan to work with him again. Highly recommended.
Valentyn S.Status: Offline

About Valentyn

Valentyn S.Status: Offline
Fullstack SaaS Engineer & AI Developer React NodeJS Claude RAG agents
100% Job Success
5.0  (23 reviews)
Chernivtsi, Ukraine - 6:02 pm local time
I help startups and B2B SaaS companies build, ship, and scale complete web applications powered by production-grade AI.

Instead of hiring separate frontend, backend, and AI infrastructure engineers, I handle the entire product lifecycle — bridging the gap between robust, scalable full-stack architecture (NextJS, NodeJS, Python, AWS) and cutting-edge GenAI implementations (RAG pipelines, autonomous agents, and LLM orchestration).

With 10+ years in full-stack development, $200K+ earned on Upwork, and a 100% Job Success Score (Top Rated Plus), I build with an ownership mindset to ensure your MVP hits the market fast and scales smoothly.

━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
🌐 FULL-STACK & AI CAPABILITIES — WHAT I BUILD
━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
→ Full-Stack SaaS Platforms: Complete web applications with responsive UIs, secure multi-tenant auth, and complex business logic (React, NextJS, TypeScript).
→ AI Agents & Agentic Workflows: Multi-agent systems capable of autonomous execution, tool usage, and function calling (OpenAI, Claude, Gemini).
→ Production RAG Pipelines: Enterprise semantic search utilizing vector databases (Pinecone, pgvector, Qdrant) for accurate, private data querying.
→ Robust Backends & APIs: Highly performant, clean-code REST/GraphQL APIs and microservices (NodeJS, NestJS, Python, Express).
→ Automated Business Workflows: Intelligent document processing, automated lead scoring, and custom CRM/ERP AI integrations.

INDUSTRIES I SERVE WITH AI + WEB SOLUTIONS:
- Multifamily Real Estate — Custom web software layered over Yardi, AppFolio, Entrata, ResMan, RealPage, Apartments com
- Hospitality / Hotels / Restaurants — AI booking flows, guest communication platforms, and review automation dashboards
- MarTech / AdTech — Complete web analytics suites integrated with AdTech and MarTech API, and others like Meta, Google, TikTok, Yelp, and UberEats APIs

━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
🏆 RESULTS FROM RECENT PROJECTS
━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
✔ AI Voice Agent SaaS Platform — Complete frontend UI/UX redesign + Supabase backend refactor, delivered in 90 days ($7,000 fixed price, 5.0 ★)
✔ Senior NodeJS SaaS Integration — 816 hours of self-driven backend delivery on schedule across 6 months ($32,633, 5.0 ★)
✔ AI-Powered Real Estate Onboarding — Built the web frontend and AI backend workflow that reduced onboarding drop-off and boosted conversions.
✔ Enterprise Software — Systems built by my team are used daily by Cushman & Wakefield (Fortune 500 real estate firm).

━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
⚙️ TECH STACK
━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
AI / LLM Integration:
OpenAI API, Claude API, Gemini, LangChain, RAG, Vector Databases, Prompt Engineering, Function Calling, Structured Outputs

Backend Development:
Nodejs, NestJS, Python, Expressjs, Nextjs (Server Components)

Frontend Development:
React, TypeScript, Redux, Nextjs, Material UI, Tailwind CSS

Mobile App Development:
Flutter (Cross-platform, CI/CD with Codemagic)

Cloud & DevOps:
AWS (SQS, SNS, Lambda, RDS, ECS, ECR, CloudWatch, EventBridge, VPC, Route53, EC2), Terraform (IaC), Docker, Docker Swarm, Nginx

Databases & Caching:
PostgreSQL, MongoDB, MySQL, Redis, Pinecone, Qdrant, pgvector

API & Enterprise Integrations (50+ types):
REST / GraphQL / SOAP · OAuth2 / OIDC · Webhooks · ETL Pipelines · Payload Encryption

━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
🏢 ENTERPRISE & THIRD-PARTY INTEGRATIONS
━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
Property Management Systems (PMS):
Yardi Voyager · AppFolio · Entrata · ResMan · RealPage · Apartments com

Marketing & Social Platforms:
Meta (FB/IG) · Google Suite · Twitter/X · TikTok · Yelp · UberEats

Past Enterprise Client Impact:
STIHL · Liebherr · Cushman & Wakefield

━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
🤝 HOW WE WORK TOGETHER
━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
→ Discovery call → System architecture proposal → Milestone-based delivery
→ MVP in 6–12 weeks, production-ready scaling in 18–32 weeks
→ Available 30+ hrs/week, response time within 4–8 hours
→ Backed by a distributed team across 🇺🇦 🇵🇱 🇮🇹 🇷🇴 🇨🇦 if you need to scale resources rapidly

I prioritize long-term, high-trust partnerships over quick fixes — 29 completed projects with an average engagement of 12-24 months.

Let's jump on a call and map out what you're building.

Steps for completing your project

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

Delivery time starts when Valentyn receives requirements from you.

Valentyn works on your project following the steps below.

Revisions may occur after the delivery date.

UI/UX design

Please, send us your design file and let's get started.

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