Kotlin with Spring or Node with Express: Which Offers Better Performance?

A lot of bottlenecks in performance usually stem from database queries and external API calls rather than the frameworks themselves. Make sure your database queries are efficient, or you could run into issues like locking tables or overwhelming memory with large data sets. Both Node and Java can scale horizontally, but the design of your DB and queries is key to performance.

Generally, Kotlin tends to have better performance since it runs on the JVM, but first, you should identify what level of performance you need for your application. Without that clarity, it’s hard to determine how much optimization is necessary.

Before diving into a choice, it's crucial to set clear performance targets. If you're hearing claims about Java underperforming, don't overlook advancements like CRaC, GraalVM, and other cloud-native concepts that can actually help Java perform on par with or even better than Node.

If you're really after top-tier performance, consider Rust with Axum. However, keep in mind that for most projects, the language choice isn't as crucial as understanding the workload and performance requirements. Answering questions about expected requests per second and maximum response times can guide your decision more accurately than just language comparisons.

A good approach is to build a simple proof of concept in the language you're most comfortable with. This will help you establish performance benchmarks and see if your application meets the needs. If it doesn't, you'll have a good idea of whether you can optimize it further or if you need to switch languages for a new prototype. Focus on reliability through proper design and testing after you've made your initial choice.

There's really no straightforward answer without knowing your performance goals and system design. If you don't have to create your own system, consider using existing PBX solutions. Sometimes wanting to build something from scratch can lead to unnecessary complexity. Think about your overall strategy first.