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You will get get full stack developer to build the back end on your SaaS MVP | Python

Serhiy L.Status: Offline
Serhiy L. Serhiy L.
5.0
Top Rated
Preview imagePreview image

Let a pro handle the details

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

Let a pro handle the details

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

Project details

You need a reliable partner for robust SaaS MVP back end development and a comprehensive server audit. You need a dedicated back end developer and full stack developer mastering SaaS architecture across Python and JavaScript

We take startups from "Zero to One" with tailored SaaS MVP back end development. Every full stack developer and back end developer acts as your technical co-founder. We excel at secure SaaS data foundations, rigorous server audits, and scalable architectures using Python, TypeScript, and JavaScript.

Why choose us?

Python Expertise
We build secure, scalable back-end systems using FastAPI, Django, and Flask, following industry best practices.

Scalable SaaS Architecture
We create foundations that support long-term growth.

100% IP Ownership

MVP-Focused Development
We prioritize the features that matter most, helping you launch faster, validate your idea, and maximize ROI.

Transparent Collaboration
Clear communication, regular updates, and a product-oriented approach throughout the development process.

Let's build your SaaS MVP with a reliable Python development team.
Programming Languages
JavaScript, Python, TypeScript
Coding Expertise
Cross Browser & Device Compatibility, Performance Optimization, Design
What's included
Service Tiers Starter
$1,550
Standard
$11,000
Advanced
$25,500
Delivery Time 7 days 25 days 55 days
Number of Revisions
124
Design Customization
-
-
Content Upload
-
Responsive Design
Source Code
5.0
12 reviews
100% Complete
(12)
1% Complete
(0)
1% Complete
(0)
1% Complete
(0)
1% Complete
(0)

OM

Oleksii M.
5.00
Apr 20, 2026
Senior Full Stack Developer, Software Architect (SaaS, .NET, React, Rust) We enjoyed working with Serhiy on our solution architecture technical audit and code review, he helped our team to identify technical design issues and improve it, also suggested cool engineering AI tools for our dev team, so we highly recommend him and will be happy to work again.

VP

Viktoria P.
5.00
Nov 25, 2025
Java Developer with experience in Spring, Kubernetes and Hibernate on AWS Working with Serhiy and the Genius team was a game-changer for our complex Java project! They delivered every feature on time, kept communication crystal clear, and even elevated our solution architecture. Highly recommended — we’d gladly team up again!

JB

Jordi B.
5.00
Jun 19, 2024
Senior Rust Developer

JB

Jordi B.
4.85
Jun 19, 2024
Rust developer

OM

Oleksii M.
5.00
Dec 29, 2023
Senior Full-Stack Developer (C#, Angular) We very enjoyed working with Genius team on our web-app project and they helped our team to deliver this project within the deadline. All new features were delivered as planned using clear communication, they also helped with the solution architecture improvements so we highly recommend this team and will be happy to work again, thanks guys!
Serhiy L.Status: Offline

About Serhiy

Serhiy L.Status: Offline
Full Stack Developer | AI Developer | SaaS | React Node .NET Rust Web3
100% Job Success
5.0  (12 reviews)
Warsaw, Poland - 12:56 am local time
Hello and welcome to my profile!🤝🙂

🔥 I help startups and global businesses (Pfizer, Deutsche Bank, ING, Upwork, KLM, ) build, scale, and support AI SaaS products, acting as a lead full stack developer and mobile app developer so you don't need to assemble a full team just to get moving. If your project needs a highly interactive frontend built by a specialist react developer, or use Vue and Angular, a scalable .NET or Golang architecture, a custom CMS handled by a senior wordpress developer, or a dedicated Back End Developer building secure Rust and Solana microservices, I cover it as your full stack developer and software developer, so you get one point of ownership instead of five disconnected specialists. My deep expertise in JavaScript, PHP, and AI integrations, combined with an understanding of SaaS sales and SaaS marketing, means the SaaS applications I build are engineered to actually convert and scale, not just function.

⭐ Certified full stack developer, React developer, software developer, & SaaS developer Top Rated+
🏆100% full stack developer Success for every SaaS contract utilizing React, Vue, Angular, Node.js, Python, Golang, Rust
⭐ 5-star Rating for web, mobile app developer projects, AI, Web3 Solana, and SaaS
💰 $300K+ earned delivering excellence as an elite full stack developer, web developer, software developer, and wordpress developer.

Whatever stage your product is at, I bring extensive full stack developer and software developer expertise across Web, Mobile, and SaaS platforms to get you there, seamlessly integrating AI models and Web3 components (including Solana smart contracts) into robust web systems built for your business. Whether architecting a new SaaS platform in .NET, optimizing core financial engines in Rust or Golang, deploying a custom theme as a wordpress developer, boosting technical infrastructure for FinTech, MarTech, PropT SaaS products, or scripting in Python for complex data processing. My full stack developer and SaaS developer approach covers every Web, Mobile, AI, Data, Web3 projects domains.

My skills as a full stack developer, React developer, data developer, SaaS developer, web developer, mobile app developer, and back end developer:

✅React (lead react developer, MERN stack)
✅Vue
✅Angular
✅Node.js
✅Python
✅Golang
✅.NET (Web APIs, legacy migrations)
✅Rust (memory-safe modules, solana ecosystems)
✅PHP (stable databases)
✅JavaScript (core & advanced ecosystems)
✅WordPress / Custom CMS
✅AI Adoption & Integrations
✅Web3 / Solana smart contracts
✅iOS/Android (mobile app developer)
✅Agile & Scrum/Kanban delivery

Stack of technologies I use as your full stack developer:
✅ Frontend: React, Vue, Angular
✅ Backend & APIs: Node.js, .NET Web APIs, Golang, PHP
✅ Data & scripting: Python (complex data processing)
✅ Blockchain: Rust-based Solana microservices, Web3 smart contracts
✅ CMS: bespoke WordPress builds and custom themes
✅ AI: model integrations for smart SaaS features
✅ Mobile: iOS/Android builds as mobile app developer

By combining core JavaScript, advanced React/Vue/Angular ecosystems, scalable Node.js and Golang microservices, stable PHP databases, and smart AI features, I deliver exactly what you need from a top-tier full stack developer, cross-platform mobile app developer, software developer, and Back End Developer.

Industries where I bring solid full stack developer, software developer, and SaaS developer experience:
✅AI Development, AI Agents, AI Integration, Web3, Blockchain
✅Data Engineering (Cloud, AI, ML, Vector, SQL, NoSQL)
✅Finance (FinTech SaaS, data analytics via Python, Golang, Rust)
✅PropTech (SaaS, CRM, Rich UIs via JavaScript, Vue, Angular, React)
✅HRTech/EdTech (SaaS solutions)
✅Travel/Hospitality (SaaS platforms)
✅eCommerce (web portals via .NET, PHP)

As a dedicated lead React full stack engineer, react engineer, Node.js Architect, Back End Developer, and strategic SaaS developer, I blend AI performance, Golang APIs, and Rust (including Solana blockchains) into your traditional SaaS workflows — as your full stack developer, web developer, and mobile app developer, all in one.
🔥 Backed by certification as a Full Stack developer Engineering and Solution Architect Expert (Ph.D. CS, PMP, CSP, CSM, CSPO, ICP-PPM, MCP), I deliver Agile/Scrum SaaS solutions as a lead full stack developer, dedicated react developer, software developer, and saas developer focused on turning your web, AI, React, Vue, angular, Rust,Solana, Golang, and .NET goals into a shipped product.
🔥 Managing cross-functional teams as a full stack developer, I ensure strict coding best practices across dynamic React, Vue, and angular UIs, iOS/Android builds guided by a senior mobile app developer, Node.js, Golang, and PHP backends, Web3 Solana integrations, legacy .NET migrations, bespoke CMS builds managed by a wordpress developer, and sophisticated Python integrations designed to maximize your product business ROI.

*Updated: 21.08.26

Steps for completing your project

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

Delivery time starts when Serhiy receives requirements from you.

Serhiy works on your project following the steps below.

Revisions may occur after the delivery date.

Review requirements and existing materials.

Analyze architecture and technical feasibility.

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