Travel Recommendation System

Co-founded travel tech startup (Jan 2022 - Jul 2024): **Role**: Technical co-founder, owned technical stack **What We Built**: - Full-stack application: React frontend, FastAPI microservices, PostgreSQL - Hybrid recommendation engine: collaborative filtering (ALS) + LightGBM ranking + content-based - Integrated external APIs: hotel and flight data - Implemented Redis caching to reduce latency - Ran A/B tests to measure engagement improvements **Challenges**: - Cold start problem for new users - Data sparsity in early days - Balancing recommendation quality vs. diversity - Working with limited resources (2-3 person team) **What I Learned**: - Product development and user research - Making engineering trade-offs with resource constraints - Remote team coordination - Not everything that works in theory works in practice **Reality check**: User engagement improved but product-market fit was challenging. Project provided valuable learning experience.