Seoul Developer Builds Self-Reinforcing K-pop Music Pipeline on OCI Free Tier

A Seoul-based backend developer has built k-cosmos, a web-based 3D music space that maps K-pop tracks using 768-dimensional vector embeddings, after finding no structured K-pop metadata or emotional tag datasets publicly available. The self-reinforcing data pipeline runs on Oracle Cloud's free tier and uses Spring Boot with pgvector to continuously enrich its own music database. To prevent database connection exhaustion, the developer split external API calls and embedding generation into three decoupled transaction phases, ensuring heavy network I/O occurs outside active database connections. A two-stage SQL window function enforces artist diversity in recommendations, preventing any single artist's large discography from dominating the suggestion space. Budget controls randomize and flatten the processing queue nightly to evenly distribute API quota usage and avoid hitting free-tier LLM limits.