Java 1.9x faster.
1.9x faster.
No Spring required.
ZeroMCP vs spring-ai-mcp — HTTP benchmarks.
Throughput
4,512 req/s ZeroMCP
vs. 2,438 req/s spring-ai-mcp
Latency (p50)
0.21 ms ZeroMCP
vs. 0.32 ms spring-ai-mcp
Memory
200 MB ZeroMCP
vs. 284 MB spring-ai-mcp
HTTP Performance — Head to Head
Same hello tool. Same methodology. 5-minute sustained load in Docker. Javalin for ZeroMCP, Spring Boot for spring-ai-mcp.
req/s p50 p99 Memory CPU
ZeroMCP (Javalin) 4,512 0.21ms ~1ms 200 MB 0.16%
spring-ai-mcp 2,438 0.32ms 0.97ms 284 MB 0.22%
The tradeoff
spring-ai-mcp is Spring Boot's MCP integration — it brings the entire Spring framework, auto-configuration, and dependency injection container. ZeroMCP is one JAR (gson) on Javalin, no annotations required. That framework-free design is why ZeroMCP delivers 4,512 req/s to Spring's 2,438 and uses 200 MB versus 284 MB. Neither is wrong. spring-ai-mcp is simpler if you already live in the Spring ecosystem. ZeroMCP is simpler to keep lean.