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Fabian S.

@fabians73

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5.0
2

2.3

2.3

100%

Full‑Stack Engineer | AI, Data & Web3

$50 USD / Hour

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Spain (12:32 PM)

Joined on February 23, 2026

$50 USD / Hour

🧩 I architect and deliver production systems across web, mobile, data, and blockchain, using AI only when it clearly improves speed, usability, or decision‑making. I focus on products that stay stable under real traffic, messy data, and business pressure. 🧠 I’ve worked on full‑stack web apps, cross‑platform mobile apps, desktop tools, data pipelines, and real‑world blockchain integrations. You get one engineer who can own the journey from idea to architecture, implementation, performance tuning, and deployment – without fragile hand‑offs or glue code. 🌐 Web & Backend - ⚛️ High‑performance apps with React, Next.js, TypeScript, clean state management, and REST/GraphQL APIs. - 🛠️ Robust services with Node.js, Python, or PHP/Laravel, backed by PostgreSQL/MySQL, Supabase, or Firebase. - 🔐 Strong focus on data modeling, auth flows, background jobs, logging, and CI/CD so systems grow gracefully. 📊 Data Engineering - 🧵 ETL/ELT pipelines that move data from APIs, webhooks, and OLTP databases into analytics‑ready stores. - 🐍 Ingestion and transformation jobs (Python, SQL, queues) so dashboards and AI features get clean, reliable data. - 📈 Schemas and aggregates designed for reporting and KPIs without overloading production databases. 📱 Mobile & Desktop - 📲 Maintainable Flutter and React Native apps tuned for performance and long‑term support. - 💻 Desktop utilities in C++ and C# when low‑level performance or OS‑level integration is important. ⛓️ Blockchain / Web3 - 🧾 Solana (Rust) and EVM smart contracts designed for correctness, testing, and audit‑ready structure. - 🔗 Wallet flows, signing, backend integration, indexing, and monitoring so DApps feel like real products, not demos. 🤖 Practical AI - 💬 AI chat systems, content tools, workflow automation, and data‑driven features using LLMs, embeddings/RAG, and automation pipelines. - 🎯 Emphasis on predictable behavior, guardrails, and measurable business impact instead of random API responses. 🛠️ Clients work with me when they need a developer who thinks like an engineer: someone who clarifies requirements, surfaces architectural risks early, untangles complex bugs, and strengthens existing systems without breaking what already works. 🔧 Tech stack: React, Next.js, TypeScript, Node.js, Python, PHP, Laravel, Flutter, React Native, C++/C#, PostgreSQL, MySQL, Supabase, Firebase, ETL/data pipelines, SQL analytics, Solana (Rust), EVM smart contracts, Web3 integration, AI/LLM integration, automation, GitHub Actions, CI/CD. ✅ You get clear communication, honest timelines, and clean code – with AI, data, and blockchain used only where they truly add product value. If you want one developer who can own web, data, mobile, desktop, blockchain, and AI end‑to‑end, I’m a strong fit.

Verifications

On time

100%

On budget

100%

Accept rate

67%

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5.0 · 2 Reviews
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Build a Mini RAG FAQ Assistant (Next.js + AI) $100 USD

Good job overall. The freelancer completed the tasks as requested and responded quickly to my messages. Would work with him again.

Olitha A.

@Olitha04

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Kandy, Sri Lanka

23 days ago

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Repair Node.js CI Workflow $40 USD

Excellent! Super fast & professional. Hiring again!

Ayoma G.

@ayoi4

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London, United Kingdom

28 days ago

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Education

Universidad Politécnica de Madrid

2008 - 2012

4 years

Bachelor's Degree

Flag of

Spain

2008 - 2012

4 years

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