Open to Senior Remote Contracts

Sirin Kolasseri
AI Engineer &
Full-Stack Architect

I build production AI systems — Agentic AI backends, multi-LLM routing, MCP architectures — and ship full-stack platforms that scale. 15+ years delivering for US & EU clients.

15+
Years Experience
10+
US / EU Clients
50+
Open Source Projects
2
Live AI Platforms

Skills & Tech Stack

Deep expertise across the full AI + full-stack spectrum — from LLM orchestration to production infrastructure.

AI Engineering
LLM / GenAI Agentic AI MCP OpenAI API Claude API Ollama FastAPI STT / TTS PyTorch Machine Learning Python Scikit-Learn VectorDB RAG FalkorDB
Backend
Golang Node.js Python / FastAPI REST API GraphQL Microservices MongoDB MySQL Redis PostgreSQL Kafka RabbitMQ JWT / OAuth2 gRPC
Frontend
React.js Next.js Vue.js Angular React Native Tailwind CSS Bootstrap Recharts Vite TypeScript
Infrastructure & DevOps
AWS / EC2 Docker Kubernetes Nginx CI/CD GitLab GitHub Actions SSL / HTTPS Vercel Lambda DynamoDB Selenium / TDD

Featured Projects

Production systems built from zero — not tutorials or side projects.

AI Business Chat Bot
May 2022 – Present
AI / LLM Live Open Source

A production-deployed, full-stack AI chatbot platform for business intelligence — real-time conversational AI, hands-free voice conversation, a 25+ chart analytics dashboard, and 27 ML-powered BI reports with PDF/CSV export. Multi-LLM, multi-language, deployable on-premise or cloud.

Talk mode — sub-500ms voice via OpenAI Realtime API + WebSocket
Multi-LLM routing: Claude / GPT-4o / Groq / Cerebras / Ollama / llama.cpp
25+ analytics charts — RFM, LSTM churn, CLV, cohort, AR aging, EOQ
27 ML-powered BI reports — OLS forecasting, FP-Growth, MLP bad-debt
MCP Tool Architecture — plugs into Claude Desktop, n8n, ChatGPT
FalkorDB knowledge graph + OpenViking semantic memory (~85% token reduction)
Multilingual STT/TTS — English, Arabic, Malayalam, Hindi, Bengali, Urdu
SSE streaming with step-by-step execution visibility
PythonFastAPI React.jsVite OpenAI Realtime APIClaude API GroqOllama FalkorDBfaster-whisper ElevenLabsMCP SSEWebSocket AWS EC2Recharts
StartPOS — AI-Powered POS & ERP
Jan 2022 – Present
AI / ML Live Open Source

Open-source Point of Sale & ERP system for the Saudi Arabian market with a full AI layer — ask your business anything in plain English or Arabic and get instant answers, live charts, and forecasts. ZATCA Phase 1 & 2 certified for Saudi e-invoicing (Fatoora).

50+ analytics charts + 33 ML-powered BI reports
ZATCA Phase 1, 2 & B2B certified — ECDSA-signed invoices
6-month revenue/expense/profit forecasting with confidence intervals
Customer RFM segmentation, LSTM churn risk, CLV prediction
WhatsApp invoice delivery via Evolution API
Full double-entry accounting · multi-store · multi-warehouse
MCP integration — Claude Desktop, ChatGPT, n8n compatible
Voice mode with multilingual STT/TTS
GolangPython FastAPIReact.js MongoDBRedis Claude APIGPT-4o GroqOllama FalkorDBMCP Bootstrap 5JWT AWS EC2

More Projects

Wolfpack
Nov 2023 – Jan 2024 · Denmark
Denmark's easiest expense-sharing app — available on iOS & Android.
Spring Boot · PostgreSQL · Angular 14 · React Native
Sunburst
Nov 2021 – Oct 2023
Aircraft Maintenance Management System.
Golang · GraphQL · MSSql · Vue.js · Redis · Docker
Pantacor Platform
Nov 2018 – Sep 2020 · London, UK
Linux firmware sharing & deployment platform for IoT devices at scale.
Golang · MongoDB · GraphQL · Kubernetes · Kafka
Haikujam
May 2015 – Oct 2016 · London, UK
Collaborative haiku-writing mobile app with real-time social features.
Yii2 · Node.js · Angular · MySQL · Redis · AWS
Staff Allocation Solution
2013 · Florida, USA (2amigos)
Staff utilization & profitability tracking platform.
Yii1 · Node.js · MySQL · Redis · TDD
Engineering Doc Control System
2014–2015 · Kazakhstan
Document control system for construction companies.
Yii2 · Node.js · Angular · MySQL

Work Experience

13 roles across US, EU, GCC, UK, and India — predominantly remote since 2013.

Technology Consultant Startup Tech. Consultancy LTD Remote Feb 2024 – Present · London, UK
Golang · React.js · Python · FastAPI · LLM · GenAI · Agentic AI · MCP · Ollama · AWS
Full Stack Developer N30 Aps Remote Nov 2021 – Jan 2024 · Copenhagen, Denmark
Golang · Node.js · MongoDB · MSSQL · Vue.js · React.js · AWS
Technology Consultant Startup Tech. Consultancy LTD Remote Aug 2021 – Oct 2021 · London, UK
Golang · Node.js · MongoDB · Vue.js · React.js · AWS
Technology Consultant 2amigos Remote May 2021 – Jul 2021 · Florida, USA
PHP · Yii2 · MySQL · MongoDB · Vue.js · React.js · AWS
Sr. Software Engineer Pantacor Remote Nov 2018 – Sep 2020 · London, UK
GoLang · GraphQL · MySQL · MongoDB · Kubernetes · Kafka · Docker
CTO Nintriva Jan 2017 – Oct 2018 · Kochi, India
GoLang · GraphQL · PHP · Yii2 · MySQL · MongoDB · AWS
Lead Web Engineer Haikujam Remote May 2015 – Oct 2016 · London, UK
PHP · Yii2 · Node.js · MySQL · MongoDB · Redis · AWS
Technology Consultant 2amigos Remote Mar 2013 – Aug 2013 · Florida, USA
PHP · Yii1 · Node.js · MySQL · MongoDB · Redis

What Clients Say

LinkedIn recommendations from clients across Denmark, UK, USA, Spain, and Australia. View on LinkedIn →

"Sirin is a very skilled and experienced Senior Full Stack Engineer with a great grasp of architecture patterns such as Micro Services. Sirin's delivery mindset is also exceptional."
Co-Founder & CEO · N3O Aps, Denmark
"During Sirin's time at Pantacor he excelled in tackling new problems and finding quick but clean solutions, as well as innovative architecture ideas for our fast growing backend infrastructure."
Co-Founder & CEO · Pantacor Ltd, UK
"Sirin is a rare find — someone who really cares about work and customers. Trust Sirin to make things happen!"
Sr. Software Dev Manager · Amazon, USA
"Sirin is an excellent developer — his team offers top-quality software development covering a wide range of languages & frameworks. Responsive & personable."
VC Investor & COO · COPRESENCE, London
"Sirin has repeatedly proven to be a reliable coworker. He has always been available, effective and fast when solving problems."
Embedded Software Engineer · Pantacor, Spain
"Sirin and his team are great to work with — they produce the goods and deliver the software on time and in line with the client's expectations."
Superintendent · Water Corporation, Australia

Open Source Contributions

Yii framework extensions used by thousands of developers worldwide.

Full-stack AI-powered POS & ERP backend in Golang
React.js frontend for StartPOS
Bitcoin / Coinbase API integration for Yii
Braintree payment integration for Yii
PayPal Express checkout for Yii
Production-ready Go microservice with OAuth2, MongoDB, Redis
Available for Hire

Hire Sirin as a Senior Developer

Contract · Freelance · Full-time · Remote · Immediate start · £450–£900/day

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FAQ

Common Questions

How do I hire Sirin as a freelance Golang or AI developer? +

The fastest way is to email sirinibin2006@gmail.com or connect on LinkedIn with a brief description of your project or role. I respond within 24 hours. After an initial call to scope requirements, I provide a written proposal with timeline, rate, and contract structure. For short-term engagements I typically work through Startup Tech Consultancy LTD (UK Company No. 12479922), which simplifies invoicing for EU, GCC, and US clients. Engagements can start within 1–2 weeks of agreement.

What is Sirin Kolasseri's day rate and availability? +

Day rates range from £600–£800/day for Golang backend engineering and £700–£900/day for AI engineering (LLM integration, agentic AI, FastAPI). Full-stack and React roles are typically £500–£750/day. I am available for immediate start on freelance and contract engagements. I work remotely across GMT, CET, GST, IST, and PST timezones — no location constraint for EU, Middle East, India, or North American clients.

What AI and LLM technologies does Sirin specialise in? +

I build production AI systems using OpenAI GPT-4o, Anthropic Claude (with MCP), Google Gemini, and Groq. My specialities are agentic AI (multi-step tool-using agents), RAG pipelines with pgvector and Pinecone, voice AI using OpenAI Realtime API and ElevenLabs, and MCP server authoring for Claude Desktop integrations. I use Python FastAPI for AI backends and Golang for the orchestration layer. I have delivered production AI systems including the AI Chat Bot (StartPOS multi-LLM assistant) and multiple client LLM integrations.

Has Sirin delivered ZATCA Phase 2 compliance projects? +

Yes. I built ZATCA Phase 1, Phase 2, and B2B clearance compliance from scratch for StartPOS — including ECDSA cryptographic signing, TLV-encoded QR code generation, UBL XML invoice generation, and B2B clearance integration with the ZATCA Fatoorah API. The solution has a zero-rejection rate in production. For new client projects I can typically deliver a working ZATCA Phase 2 integration within 4–5 weeks of engagement start, including ZATCA-certified testing and sign-off.

What is Sirin's experience with Golang microservices? +

I have built Golang systems in production for 8+ years. The most significant is StartPOS — a full ERP/POS platform with 8 Go microservices handling 10,000+ daily transactions on AWS EC2, with MongoDB, Redis, and JWT authentication. I also built the AI Chat Bot orchestration layer in Go — routing between 5 LLM providers with sub-500ms response time. My Go work covers REST APIs, gRPC/Protobuf, goroutine-based concurrency, Docker multi-stage builds (images under 20MB), and Kubernetes deployments.

Available for Senior Remote Contracts

Golang · Python · AI/LLM · React.js · Full-Stack · Architecture
EU · US · Middle East · India · Asia-Pacific · Immediate start
GMT, CET, GST, IST, PST timezone coverage available