Koray Cetin

- Co-led the development of Facedance, Voi, and Retake (AI-based apps with 75M+ total downloads) - Built and maintained Python–Node.js backends serving AI model results, optimizing performance and cost at scale - Fine-tuned and merged AI models, managed a shared codebase with ~10 contributors, and improved inference/training pipelines - Handled large user-specific models: dynamic fetching, optimized storage, and backend response time improvements - Managed and optimized a large Kubernetes cluster

- Built advanced personalizations using pure JavaScript, including recommendation engines, social proof widgets, in-mail content injection, and push notifications - Collaborated with global partners across industries such as Nike, Mavi, Philips, and AirArabia to implement and optimize growth solutions - Delivered critical customizations and feature deployments under time-sensitive conditions - Contributed to Insider’s in-house full-stack KPI monitoring platform, implementing new features

- Built scalable backend systems and real-time matchmaking servers for Sociable and Hola, enabling video calls and multiplayer board games - Developed and maintained backend logic for games like Match Pairs and Four in a Row, including a reusable timer service - Packaged backend features as reusable NPM submodules and ensured quality with unit tests using Mocha - Contributed to client-side development in Kotlin and helped implement key social features like Stories

Data Analytics in Applications, Computer Vision III: Detection, Segmentation, and Tracking, Data Mining and Knowledge Discovery, Advanced Topics of Software Testing, Introduction to Deep Learning, Modelling and Simulation

Development in Software Engineering, Fundamentals of Software Engineering, Introduction to Database Systems, Analysis of Algorithms, Principles Of Programming Languages, Data Structures and Algorithms, Introduction to Object Oriented Programming, Introduction to Information Retrieval, Applied Computer Networks