Same API in Java, Go, Rust, and Kotlin — a 4-language benchmark

A developer with 21 years of Java experience rebuilt the same short-video platform API in Java, Go, Rust, and Kotlin to compare performance. Key findings: Kotlin nearly matched Go in throughput (99K vs 100K QPS), Rust used dramatically less memory (33 MB vs Go's 60 MB at 500 concurrent), and Go had the fastest cold start (69ms). Rust (Axum) was chosen for production due to infrastructure cost savings from lower memory usage, though Go is recommended for fast team shipping and Kotlin for existing JVM investments.