Junior full stack developer · Porto · Available now

I build and ship full stack web apps — and the AI features inside them.

I'm a Computer Science student at the University of Porto. I take web apps from database schema to deployed product with Next.js, FastAPI and PostgreSQL, and integrate AI through LLM APIs, RAG and embeddings where it solves a real problem.

Portrait of Ben Lubetzky

Selected work

Deployed apps, built end to end.

BookMatch swipe screen showing a book card with pass and save buttons
Team of 2 · Live

BookMatch

Swipe-based book recommendations. Readers swipe through books; a vector search over a shared book/reader space decides what comes next.

  • Next.js swipe interface on an async FastAPI + PostgreSQL API, with JWT auth and a 5-language UI
  • Recommendation engine built on pgvector KNN search
  • 20+ migrations, row-level security and nightly backups via GitHub Actions

Next.js · TypeScript · Tailwind · FastAPI · PostgreSQL · pgvector

LedgerDrop invoice workspace with an upload area and a recent documents list
Solo · Live

LedgerDrop

Invoice processing with a human in the loop. Invoices are extracted and validated automatically; the uncertain ones go to a review screen.

  • Async FastAPI pipeline with LLM extraction through the OpenAI API
  • Next.js review screen to approve, reject or correct, with a full audit trail
  • Deployed with Docker on Render, files stored in Cloudflare R2

FastAPI · SQLAlchemy · PostgreSQL · Next.js · TypeScript · Docker · OpenAI API

Customer support demo with test scenarios on the left and a chat window on the right
Solo · Live

Customer Support Agent

An LLM-powered support backend that can act on orders safely: the model chooses the action, the code decides what's allowed.

  • FastAPI backend where an AI agent handles orders through typed tools
  • Refund rules stay in code, not in the prompt
  • Policy answers grounded with RAG; risky requests escalate to a human

Python · FastAPI · OpenAI API · RAG · ChromaDB · SQLite · Docker

More projects

AI integration · RAG

Research Paper Assistant

Question answering over computer-vision papers with structure-aware chunking, hybrid retrieval and cited answers.

Python · FastAPI · Embeddings · ChromaDB

Frontend · Web app

Spanish Learning Website

A spaced-repetition vocabulary trainer with typed recall in both directions, pronunciation playback and progress tracking.

JavaScript · Web Speech API · Local storage

Earlier work · machine learning

Skills

Frontend
TypeScript, JavaScript, React, Next.js, Tailwind CSS
Backend
Python, FastAPI, REST APIs, SQLAlchemy, JWT auth
Databases
PostgreSQL, pgvector, SQLite, Alembic migrations
Tools & deployment
Git, GitHub Actions, Docker, Render, Cloudflare
AI integrations
OpenAI API, RAG, embeddings, PyTorch

About

I like owning the whole path of a feature: the schema and its migrations, the API, the interface people actually use, and the deployment, backups and auth around it.

When a product needs AI, I treat it as one more integration, not the whole product. The model extracts, retrieves or suggests; validation, permissions and business rules stay in code, and a person reviews whatever the system isn't sure about.

  • BSc Computer Science University of Porto (FCUP) 2024 – Sept 2027 (expected) Coursework: Databases, Data Structures, Algorithms, Computer Networks
  • Deep Learning Specialization DeepLearning.AI · Coursera Jan 2026
  • Computer Science coursework Open University of Israel 2023 – 2024
HebrewNative
EnglishNative
PortugueseC1
FrenchB1
SpanishB1

Looking for a junior full stack developer?

I'm available immediately, based in Porto, and happy to talk.

b0508181058@gmail.com