Cross-language gRPC key-value server and client implementations across 11 languages (Go, Python, Ruby, C++, Node.js, Java, Kotlin, Scala, Rust, Dart, C#), built to surface a bug in gRPC’s BoringSSL TLS layer: a version check causes gRPC to advertise only P-256 during handshakes, silently breaking P-384 and P-521 connections in Python, Ruby, and C++. Includes the patch, test certificates for each curve, and a Docker environment for reproducible cross-language testing.