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Alex Arvanitidis

Machine Learning Engineer

Engineering scalable AI systems, building and deploying deep learning models, fine-tuned LLMs, and AI agents on AWS, with a strong full-stack engineering background of 10+ years.

Selected Projects

QSARion AI Agent

A chemical AI agent that can predict molecular properties given a substance.

Jaqpot

A machine learning model hosting platform, handling deployment, API management, and fine-tuning.

Readon.gr

A Greek social platform for open discussion, community building, and content sharing through posts, comments, and voting.

Geras

A silly little game I developed with Phaser 3 during the Covid19 quarantine.

Winnie

A Command Line Interface (CLI) consuming an actively written-to CLF HTTP access log written with Node.js

Work Experience

Blog

The 5 worst bugs I've seen on production - #1 the N+1 problem

A tiny JOIN turned one request into ~100 queries—the graph looked like a heartbeat.

The 5 worst bugs I've seen on production - #2 the infinite crawler

A 'Back to start' button shared the Next selector, looping forever and flooding the DB.

The 5 worst bugs I've seen on production - #3 the €300,000 double refund

A refund path ran twice for 15 minutes, costing €300k before a sanity check caught it.

The 5 worst bugs I've seen on production - #4 the $60 otp ddos

An OTP endpoint was abused across many IPs; budget burned twice after no action items.

The 5 worst bugs I've seen on production - #5 the animation memory leak

Long sessions leaked ~2MB per animation; snapshots revealed unreleased lottie instances.

Microlearning is the new way to learn

How I use microlearning to keep up with fast-moving tech trends through short, daily doses of content across social media and YouTube.

Coding with Claude code and LLMs: What I've learned after 3 months

Reflections on working daily with Claude Code and LLMs for three months, the benefits of full repo context, and why experience still matters.

My experience with arrogant developers

A reflection on developer culture, code consistency, and the damage caused by ego-driven decisions in software teams.

The luxury of letting ideas marinate

This post explores the power of letting ideas sit. It reflects on how having time, space, and a clear mind can lead to better solutions , especially in engineering and research. It contrasts rushed patches with well-thought-out fixes that emerge when pressure is low and the mind is calm.

I asked AI about the future of AI (Yes, AI-ception)

I wanted to know: where is AI going in the next 10+ years? Is diving deeper into large language models (LLMs) in 2025 still a good bet for developers like me? What jobs will rise? What skills will matter?

Connect

Feel free to contact me at alex.arvanitidis0@gmail.com