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I’m Ionut Barbu, a Senior Full-Stack Software Engineer and AI Application Engineer with 16+ years of experience building and operating scalable SaaS platforms, distributed backends, and cloud-native systems. I enjoy owning products end-to-end—from system design and implementation to testing, deployment, observability, performance tuning, and production support. A big focus of mine is bringing GenAI into real workflows: integrating LLMs with RAG, embeddings, vector search, structured outputs, and reliable tool/function calling. I’ve architected and delivered AI-enabled enterprise features using OpenAI and Anthropic APIs, while maintaining validation, access controls, error handling, and strong reliability practices.…I’m Ionut Barbu, a Senior Full-Stack Software Engineer and AI Application Engineer with 16+ years of experience building and operating scalable SaaS platforms, distributed backends, and cloud-native systems. I enjoy owning products end-to-end—from system design and implementation to testing, deployment, observability, performance tuning, and production support. A big focus of mine is bringing GenAI into real workflows: integrating LLMs with RAG, embeddings, vector search, structured outputs, and reliable tool/function calling. I’ve architected and delivered AI-enabled enterprise features using OpenAI and Anthropic APIs, while maintaining validation, access controls, error handling, and strong reliability practices.

Ionut Barbu

Full Stack Developer, Software Engineer, AI Engineer, +2

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I’m Ionut Barbu, a Senior Full-Stack Software Engineer and AI Application Engineer with 16+ years of experience building and operating scalable SaaS platforms, distributed backends, and cloud-native systems. I enjoy owning products end-to-end—from system design and implementation to testing, deployment, observability, performance tuning, and production support. A big focus of mine is bringing GenAI into real workflows: integrating LLMs with RAG, embeddings, vector search, structured outputs, and reliable tool/function calling. I’ve architected and delivered AI-enabled enterprise features using OpenAI and Anthropic APIs, while maintaining validation, access controls, error handling, and strong reliability practices.…I’m Ionut Barbu, a Senior Full-Stack Software Engineer and AI Application Engineer with 16+ years of experience building and operating scalable SaaS platforms, distributed backends, and cloud-native systems. I enjoy owning products end-to-end—from system design and implementation to testing, deployment, observability, performance tuning, and production support. A big focus of mine is bringing GenAI into real workflows: integrating LLMs with RAG, embeddings, vector search, structured outputs, and reliable tool/function calling. I’ve architected and delivered AI-enabled enterprise features using OpenAI and Anthropic APIs, while maintaining validation, access controls, error handling, and strong reliability practices.

Available to hire

I’m Ionut Barbu, a Senior Full-Stack Software Engineer and AI Application Engineer with 16+ years of experience building and operating scalable SaaS platforms, distributed backends, and cloud-native systems. I enjoy owning products end-to-end—from system design and implementation to testing, deployment, observability, performance tuning, and production support.
A big focus of mine is bringing GenAI into real workflows: integrating LLMs with RAG, embeddings, vector search, structured outputs, and reliable tool/function calling. I’ve architected and delivered AI-enabled enterprise features using OpenAI and Anthropic APIs, while maintaining validation, access controls, error handling, and strong reliability practices.

Skills

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Intermediate

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Intermediate

Work Experience

Senior Full-Stack & AI Engineer at UiPath

June 1, 2022 - Present

Architected and delivered scalable SaaS capabilities across frontend, backend, data, and cloud infrastructure using TypeScript, React, Next.js, Node.js, Python, FastAPI, PostgreSQL, and AWS. Designed AI-enabled enterprise workflows combining LLM integration, RAG, embeddings, semantic retrieval, vector search, structured outputs, agent orchestration, and tool calling. Built document processing and retrieval pipelines (chunking, embedding generation, indexing, retrieval, reranking, and context construction). Implemented validated tool/function calling workflows enabling LLMs to invoke approved backend services. Improved REST and GraphQL performance by analyzing service logic, database access, serialization, and caching; optimized PostgreSQL via indexing, query-plan analysis, SQL optimization, and better data-access patterns. Reduced AI workflow latency through prompt/context optimization, caching, asynchronous processing, and retrieval tuning. Added reliability controls for AI workflows

Senior Full-Stack Software Engineer at Spotify

March 1, 2018 - May 1, 2022

Designed and developed high-traffic web applications using React, TypeScript/JavaScript, Node.js, Python, PostgreSQL, Redis, and AWS. Built reusable frontend architecture and components for maintainable, responsive, and scalable product experiences. Improved performance through code splitting, lazy loading, browser caching, bundle optimization, and rendering improvements. Designed and maintained backend APIs and services supporting large-scale workloads, identifying and resolving bottlenecks across service logic, database access patterns, and API execution paths. Implemented Redis caching strategies to reduce database operations and improve responsiveness. Helped migrate legacy functionality toward independently deployable microservices to increase scalability and fault isolation. Designed asynchronous and event-driven processing workflows to increase throughput and reduce coupling. Optimized PostgreSQL queries with indexing and transaction/access pattern improvements. Integrated inter

Full-Stack Software Engineer at Booking.com

January 1, 2014 - February 1, 2018

Developed scalable customer-facing web applications using JavaScript, React, Node.js, Python, and SQL with HTML5/CSS3. Built frontend components and workflows for responsive, high-traffic user experiences and integrated them with REST APIs and data services. Improved page-load and runtime performance via asset optimization, browser caching, rendering improvements, and efficient resource loading. Designed and optimized backend services for customer-facing functionality and internal workflows by profiling API execution paths to find application and database bottlenecks. Improved database performance through SQL optimization, indexing, query restructuring, and more efficient data-access patterns. Created reusable frontend components and shared patterns to reduce duplicated implementation and improve consistency. Expanded automated testing and regression coverage for critical product workflows. Participated in production debugging, incident resolution, code reviews, and release support; co

Software Developer at Endava

June 1, 2010 - December 1, 2013

Developed customer-facing web applications using JavaScript, HTML, CSS, SQL, and REST APIs. Implemented frontend functionality and integrated applications with backend services and relational databases, building API-driven workflows for dynamic data retrieval and user interactions. Improved client-side performance by optimizing JavaScript execution, browser rendering, asset delivery, and resource loading. Refactored repeated frontend logic into reusable components and shared implementation patterns. Diagnosed defects across frontend/backend/API integration across environments. Improved browser compatibility and responsive behavior. Expanded testing practices to identify regressions prior to releases, and contributed in Agile development including code reviews, debugging, deployment support, and collaborative feature delivery.