Alexandru Ion
Senior Full Stack & Backend Engineer | Python & AI-Focused Systems
Hunedoara, Hunedoara County, Romania
LinkedIn: https://www.linkedin.com/in/alexandru-ion-a2/
Profile
Senior Backend & Full Stack Engineer with 9+ years of experience designing scalable
production systems used by thousands of customers across food tech, fintech, and high-traffic ecommerce platforms.
Strong background in backend architecture, distributed systems, API design, and data modeling.
Experienced in Node.js/TypeScript and SQL/NoSQL systems, with growing focus on Pythonbased services and AI-powered workflows including LLM integrations, embeddings, and
intelligent automation.
Proven record of leading architecture initiatives, migrating monoliths to microservices,
improving system reliability, and enabling 400% business growth through platform
modernization.
Core Skills
Backend & Systems
Python (API development, scripting, automation)
Node.js (TypeScript), GraphQL, REST APIs
Microservices & modular architecture
Authentication & authorization systems
WebSockets & real-time data flows
AI & Data
LLM integration (OpenAI/GPT APIs)
Prompt engineering & structured output pipelines
Embeddings & semantic search concepts
Data preprocessing & transformation pipelines
Production observability for AI workflows
Databases
MySQL, Postgresql, SQLite
SQL fundamentals (schema design, query optimization)
Neo4j (graph modeling)
Firebase (real-time database)
Data modeling for high-volume production systems
Frontend
React, TypeScript
Responsive UI systems
API-driven frontend architecture
DevOps & Delivery
CI/CD pipelines
Production debugging & monitoring
Performance optimization
Cloud-ready architecture patterns
Agile / Scrum leadership
Professional Experience
Beaverr Territory SRL — Senior Full-Stack Developer (Full-time)
Mar 2021 – Nov 2025 | Remote / Romania
Designed and developed Python-based backend services for automation workflows, API
integrations, and internal operational tooling.
Built RESTful APIs and backend utilities in Python to process, validate, and transform
third-party data for production systems.
Increased team productivity by 3× by introducing a lightweight task validation process
(clear acceptance criteria, fast reviews, predictable handoffs).
Delivered a rental property reviews aggregation MVP in 2 months using React and
Firebase, prioritising rapid iteration and maintainable architecture.
Developed React UI for an on-demand delivery platform in the Philadelphia area,
integrating Stripe payments, GetSwift delivery tracking, and Mailchimp automation.
Improved maintainability through reusable UI patterns, consistent API contracts, and
practical performance optimisation for production usage.
Supported release execution by improving code review quality, reducing rework, and
enabling faster delivery cycles.
AI / Automation Initiatives (Python-Focused)
Designed and implemented Python-based automation services to streamline customer
communication workflows and operational decision-making.
Built structured data pipelines integrating third-party APIs, transforming and validating
data for downstream automation and predictive logic.
Integrated LLM APIs to prototype intelligent customer-facing features, including
automated message generation and contextual response handling.
Developed backend scripts and services in Python to support data preprocessing,
workflow orchestration, and AI-assisted feature experimentation.
Improved operational efficiency by reducing manual handling of repetitive tasks through
AI-driven automation.
Pentalog — Full-Stack Developer (Full-time)
May 2017 – Oct 2020 | Remote / Romania (London-based client)
Defining architecture decisions, enforcing engineering standards, and coordinating endto-end feature delivery.
Led the migration of a legacy backend monolith to a microservices architecture,
improving scalability, deployment flexibility, and long-term maintainability.
Designed and maintained backend APIs (REST/GraphQL), optimized database schemas
and queries, and ensured high performance under increasing traffic demands.
Contributed to scaling the broader engineering organization from 4 to 26 members in two
years by participating in ~40 technical interviews and mentoring new hires.
Supported platform evolution that enabled 400% revenue growth over two years
through architectural improvements and feature modernization.
Maintained 80%+ automated test coverage using strong testing practices and CI quality
gates, increasing deployment confidence and reducing regressions.
Conducted R&D to evaluate frameworks, libraries, and architectural patterns to improve
performance, maintainability, and developer experience.
Traveled to London to deliver a time-sensitive platform duplication project,
implementing partial database sharing while preserving data integrity and minimizing
downtime.
Pentalog — Full-Stack Developer (Contract)
Feb 2016 – Apr 2017 | Remote / Romania (France-based client)
Contributed to a high-traffic e-commerce platform for a leading lens retailer processing
50,000 monthly sales and 100,000 daily visits.
Developed and maintained both frontend (Angular/JavaScript) and backend (Node.js /
REST APIs) components to support checkout, product catalog, and order management
flows.
Designed and optimized SQL queries, improving database performance and reducing
response times under peak traffic.
Diagnosed and resolved production issues using VM logs, monitoring tools, and Jira,
reducing recurring defects and improving system stability.
Led a complete website redesign across a 3-month delivery cycle, coordinating backend
adjustments, frontend implementation, and rollout.
Refactored legacy modules to improve code readability, API consistency, and long-term
maintainability.
Collaborated closely with QA, product owners, and DevOps to ensure smooth
deployments and minimal downtime during releases.
Education
Master of Business Administration (MBA) — Bábes Bolyai University, Cluj-Napoca,
Romania
2018 – 2020
