Senior Full-Stack Engineer · PHP / Python · AI-Integrated Systems · 15+ Years Berlin, Germany · hotchand.sajnani@gmail.com · LinkedIn · GitHub
I’m a senior backend and full-stack engineer with 15+ years of experience building scalable eCommerce platforms, microservices, and since 2025 AI-native systems. I’ve led monolith-to-microservices migrations, architected event-driven platforms handling 500,000+ product catalogs, and now build production RAG pipelines and LLM agents using Claude API, OpenAI API, and MCP (Model Context Protocol).
I work across PHP (Symfony/Laravel), Python (FastAPI), and modern frontend (Vue.js/Nuxt.js), with deep experience in Magento, cloud infrastructure (AWS, Docker, Kubernetes), and CI/CD. Currently freelancing out of Berlin, open to full-time, freelance, and remote-first opportunities.
AI / GenAI - OpenAI API · Claude API · RAG Pipelines · Agentic Workflows · MCP · Vector Databases · Prompt Engineering · Cursor · Claude Code
Languages & Frameworks - PHP 8 · Symfony · Laravel · Magento (1.x/2.x) · Wordpress · Woocommerce · Joomla · Typo3 · Shopware · Shopify · Python · FastAPI · Node.js
Frontend - Vue.js · Nuxt.js
Databases - MySQL · PostgreSQL · MongoDB · Redis · Elasticsearch
Architecture - Microservices · Event-Driven Systems · Monolith Decomposition · API-First · Domain-Driven Design
Cloud & Infrastructure - AWS · GCP · Docker · Kubernetes · Terraform · CI/CD (GitHub Actions, GitLab)
APIs & Auth - REST · GraphQL · OAuth 2.0 · JWT · Webhooks
Monitoring & QA - Datadog · ELK Stack · PHPUnit
Senior Software Engineer & Tech Lead (Freelance) - Berlin, Germany (Remote) March 2025 - Present Architected a full marketplace eCommerce platform with microservices, event-driven processing, and AI-powered agents (MCP, RAG, Claude API, OpenAI API), reducing operational effort by 35–70%. Led CI/CD, Kubernetes, and ELK infrastructure end-to-end; mentored 2 engineers, cutting deployment time by 60% and production issues by 30%.
Senior Backend Developer - ProByte Pvt. Ltd., Karachi, Pakistan Aug 2024 - Feb 2025 Built scalable PHP backend services, REST APIs, and enterprise OAuth integrations, reducing integration failures by 40%. Optimized high-traffic databases and async ETL processing (MySQL/PostgreSQL, Redis) for 50% faster query performance.
Team Lead / Senior Backend Engineer - Salsoft Technologies, Karachi, Pakistan Aug 2023 - Jul 2024 Decomposed a monolith into modular services, driving a 40% platform performance improvement that contributed to 15% revenue growth. Introduced CI/CD pipelines and automated testing across cross-functional teams.
Senior Software Engineer - Kaiser Inc., Karachi, Pakistan Nov 2020 – Jul 2023 Led a PHP monolith-to-microservices migration, improving scalability and fault isolation. Delivered a 40% performance uplift on a 500,000+ product catalog through caching and search optimization; mentored junior developers.
PHP Backend Developer / Tech Lead - Salsoft Technologies, Karachi, Pakistan Oct 2015 – Oct 2020 Developed and maintained Magento 1.x/2.x platforms, custom modules, and migrations. Improved store scalability through caching, DB optimization, and cloud-based CI/CD for large, high-traffic catalogs.
Earlier Experience
Browse my full repository list on GitHub.
Magento 2 - Allow Out-of-Stock Products to Be Added to Cart - Magento 2 module that removes the stock barrier at checkout so out-of-stock products can be added to cart, purchased, and fulfilled once restocked. Intercepts all three Magento 2.4.x stock-validation layers (legacy CatalogInventory + MSI) via plugins, with full store-view-scoped admin configuration. Built for Magento 2.4.x with full MSI compatibility.
Magento 2 - Free Shipping Weight Limit - Lightweight Magento 2 shipping carrier that offers free shipping up to a configurable weight threshold and automatically falls back to a flat rate above it, fully configurable from the admin panel with no code changes or theme overrides required.
Magento 2 - Content Security Policy (CSP) Whitelist Manager - Admin UI for managing Magento 2.4+’s strict CSP headers: whitelist domains per directive (script-src, img-src, connect-src, etc.), manage SHA-256 inline script hashes, and fix same-domain image blocking, all without editing csp_whitelist.xml or redeploying static content. Ships with 50+ pre-configured third-party services (GA, GTM, Stripe, PayPal, Klarna, and more).
Excel → ASCII-Cleaned MS-DOS CSV Converter - Python (pandas/openpyxl) script that converts .xlsx files to CSV, normalizing Unicode characters to clean ASCII via NFKD and enforcing strict MS-DOS (\r\n) line endings built for legacy system integrations and eCommerce feed imports that require strict ASCII/Windows-formatted output.
Bachelor of Science, Information Technology University of Sindh, Jamshoro, Pakistan · 2002 – 2006
English (Fluent/Professional) · Deutsch (A2 - Active Learner) · Urdu/Sindhi (Native)
Open to full-time, freelance, and remote-first opportunities. 📧 hotchand.sajnani@gmail.com · 💼 LinkedIn · 💻 GitHub