You will get a production B2B SaaS MVP built by a senior full stack developer team
Rising Talent
Project details
Many B2B SaaS founders find this after the first MVP failed in a B2B-specific way: single-tenant that couldn't take customer #2, a Stripe integration that broke on annual invoicing, or a stack they can't hire devs for.
Senior full stack developer studio — $4M+ earned, 100% Job Success Score, member since 2012. My team ships production B2B SaaS MVPs end-to-end: Next.js (React), Python (FastAPI), PostgreSQL (row-level security), Stripe billing, AWS. The Standard tier delivers a launchable B2B SaaS in 5 weeks: multi-tenant architecture, RBAC, Stripe billing, multi-org, audit log, webhooks, admin dashboard.
Process matches engagement: scoped requirements, written architecture, weekly demos, code review, structured handoff. We don't reach for trendy tools deprecated in 18 months — we reach for things still running when your seed round closes.
If your search took you through "b2b saas developer," "saas mvp developer," "multi-tenant saas," or "full stack developer," this is built for that buyer — a senior full stack developer team that ships B2B SaaS infrastructure right the first time.
Message me before ordering — I'll confirm tier fit and propose a delivery plan within 24 hours.
Senior full stack developer studio — $4M+ earned, 100% Job Success Score, member since 2012. My team ships production B2B SaaS MVPs end-to-end: Next.js (React), Python (FastAPI), PostgreSQL (row-level security), Stripe billing, AWS. The Standard tier delivers a launchable B2B SaaS in 5 weeks: multi-tenant architecture, RBAC, Stripe billing, multi-org, audit log, webhooks, admin dashboard.
Process matches engagement: scoped requirements, written architecture, weekly demos, code review, structured handoff. We don't reach for trendy tools deprecated in 18 months — we reach for things still running when your seed round closes.
If your search took you through "b2b saas developer," "saas mvp developer," "multi-tenant saas," or "full stack developer," this is built for that buyer — a senior full stack developer team that ships B2B SaaS infrastructure right the first time.
Message me before ordering — I'll confirm tier fit and propose a delivery plan within 24 hours.
Programming Languages
JavaScript, Python, TypeScriptCoding Expertise
Cross Browser & Device Compatibility, Security, DesignWhat's included
| Service Tiers |
Starter
$4,000
|
Standard
$8,000
|
Advanced
$14,000
|
|---|---|---|---|
| Delivery Time | 21 days | 35 days | 56 days |
Number of Revisions | 2 | 3 | 4 |
Number of Pages | 0 | ||
Design Customization | - | - | - |
Content Upload | - | - | - |
Responsive Design | - | - | - |
Source Code |
Optional add-ons
You can add these on the next page.
Express Delivery — 5 to 10 days off any tier
+$2,500
Custom CRM / Tool Integration (HubSpot, Salesforce, Slack, etc.)
(+ 10 Days)
+$2,200
60-Day Post-Launch Support
+$2,000Frequently asked questions
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NR
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Jun 9, 2022
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Gcc L.
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Eric M.
Dec 1, 2020
TCG Showdown part 2
Amazing work. High responsiveness and involvement in the project, efficient communication, promising interesting project idea, excited for more projects together!
About Kyrylo
Full Stack Developer | AI Engineer | CEO | React, Python | 4M+ Earned
100%
Job Success
Kirchhundem, Germany - 8:59 pm local time
Track record: Member since 𝟐𝟎𝟏𝟐 · 𝟏𝟎𝟎% JSS · $𝟔𝟎𝟎𝐊+ earned on this profile · $𝟒𝐌+ earned across our agency.
To be clear upfront: I don’t write the code myself on every project. As Co-Founder, I scope, architect, and oversee delivery — my Full Stack Developers and AI Engineers ship. That’s why clients hire us instead of a solo freelancer: real capacity, senior oversight, and no single point of failure.
𝐖𝐡𝐚𝐭 𝐰𝐞 𝐛𝐮𝐢𝐥𝐝
Most clients come to us with one of two problems: they need a product built properly from scratch — an MVP that ships in weeks, not quarters — or they have an existing system that needs a senior Full Stack Developer or AI Engineer team to take ownership and move it forward without hand-holding.
We’re a Full Stack Developer and AI Engineer team in one shop. That matters in 2026 because the line between the two has collapsed: modern SaaS products need React and Next.js on the frontend, Node and Python on the backend, and LangChain, RAG pipelines, and OpenAI or Claude integration as core features — not as a bolt-on. We own the whole stack end-to-end so you don’t have to coordinate three vendors.
Our Full Stack Developers ship in:
React, Next.js, Node.js, TypeScript, JavaScript, Python, Django, FastAPI, MongoDB, PostgreSQL, Supabase, Tailwind CSS, shadcn/ui, Stripe, AWS, Docker, REST APIs, third-party API integration. MERN stack and Next.js + Supabase + Stripe are our two default builds for SaaS MVPs.
Our AI Engineers ship in:
Python, LangChain, LangGraph, OpenAI API (GPT-4o, GPT-5), Claude / Anthropic API, RAG pipelines, vector databases (Pinecone, Chroma, FAISS, Weaviate), LlamaIndex, FastAPI, Hugging Face, fine-tuning (LoRA/QLoRA), n8n, Make. com, AWS Bedrock, Azure OpenAI, prompt engineering, AI agent development, chatbot development, and voice stack (Vapi, ElevenLabs, Twilio).
We don’t do prompt-only ChatGPT wrappers. Our AI Engineers ship real agentic workflows — multi-step reasoning, tool calling, memory, guardrails, and production deployment.
𝐖𝐡𝐚𝐭 𝐰𝐞 𝐝𝐞𝐥𝐢𝐯𝐞𝐫
Whether you need a React developer for a SaaS dashboard, a MERN stack developer for a full product build, an AI agent developer for a multi-agent system, a generative AI engineer for a RAG chatbot, or a Next.js developer to migrate from WordPress or Bubble — we have the right senior on the team for it.
Common deliverables: B2B SaaS MVPs from scratch, Fintech platforms with Stripe and compliance-aware architecture, RAG chatbots and knowledge-base assistants, AI automation with n8n + Claude, AI voice agents, admin dashboards with auth and RBAC, no-code-to-code migrations (Bubble/Lovable/Framer → coded stack), and ongoing engineering for products in growth.
Recent Full Stack Developer and AI Engineer projects
A snapshot of the project archetypes our team ships most often:
🔘 Fintech SaaS platforms — Next.js + Supabase + Stripe builds with subscription billing, KYC flows, role-based access, and compliance-aware architecture. Senior Full Stack Developer–led.
🔘 RAG chatbots and knowledge-base assistants — production-grade retrieval pipelines built by our AI Engineers using LangChain, Pinecone, and OpenAI or Claude, with guardrails, source citations, and LangSmith evaluation in place from day one.
🔘 AI agent and agentic workflow systems — multi-agent architectures using LangGraph, OpenAI Agents SDK, or n8n + Claude for lead generation, CRM enrichment, and internal operations automation. Built by AI Engineers who’ve shipped agents in production, not just demos.
🔘 B2B SaaS MVPs from scratch — full-cycle Full Stack Developer builds covering product architecture, React/Next.js frontend, Node or FastAPI backend, payment integration, and AWS or Vercel deployment. Designed for clients who need to launch fast and scale without a rebuild.
🔘 AI-augmented Full Stack rebuilds — taking an existing B2B SaaS or Fintech product and adding LLM-powered features (chat with your data, AI copilots, smart automation) through our combined Full Stack Developer + AI Engineer workflow. The hybrid build is what we do best.
Why clients pick our Full Stack Developer and AI Engineer team over a solo freelancer
A senior team of 9+ means we ship faster than a solo Full Stack Developer or AI Engineer and survive bus factor. CEO and Co-Founder oversight on every project means architecture decisions get made by someone with 14+ years of shipped products behind them — not by whoever happens to be assigned to your account. And because we work as a single agency rather than a marketplace of strangers, the engineer reviewing your code on Friday is the same one fixing the bug on Monday.
If you’re building a B2B SaaS or Fintech platform and need a senior team that ships, let’s talk.
Steps for completing your project
After purchasing the project, send requirements so Kyrylo can start the project.
Delivery time starts when Kyrylo receives requirements from you.
Kyrylo works on your project following the steps below.
Revisions may occur after the delivery date.
Discovery & scoping (Days 1–3)
Kickoff call. We define the target B2B customer, multi-tenant data model, RBAC structure (admin/member/viewer), billing tiers, and integration scope. You receive a one-page architecture doc before any code is written.
Multi-tenant foundation (Days 4–14)
Multi-tenant data architecture, authentication, RBAC, and Stripe billing. PostgreSQL schema with row-level security. Tenant isolation tested against real edge cases. Working preview environment by Day 14. Demo every Friday.