Cut Your .NET 10 API Startup Time by 80%: Native AOT for High-Performance

As talking about the fintech, milliseconds matter. When market conditions change, the difference between a profitable trade and a missed opportunity often comes down to how quickly your application can process and respond to incoming data. After spending the last six months optimizing a mission-critical trading API at a major financial institution, I’ve discovered that one of the most impactful performance improvements in .NET 10 isn’t getting the attention it deserves:

Native Ahead-of-Time (AOT) compilation

The results speak for themselves: our production API startup time dropped from 70ms to just 14ms — an 80% reduction — while memory usage decreased by more than 50%. For applications that need to scale rapidly during market volatility or restart quickly after deployments, these improvements directly translate to business value.

let’s walk through exactly how to implement Native AOT for your .NET 10 fintech applications with some code examples, performance benchmarks, and the lessons we learned along the way…

What Is Native AOT

Before implementation, let’s clarify what Native AOT actually does and why it matters for fintech applications specifically.

Traditional .NET applications rely on Just-In-Time (JIT) compilation, which transforms IL (Intermediate Language) code into machine code at runtime. While the JIT compiler is impressively efficient, it introduces overhead:

1. Startup delay: The first request to your API waits while the JIT compiler warms up
2. Memory overhead: Both IL and compiled machine code consume memory
3. Unpredictable performance: JIT compilation can cause periodic pauses

Native AOT takes a fundamentally different approach by performing compilation during the build process, producing a self-contained native executable with these characteristics:

• No JIT overhead: The application starts executing native code immediately
• Reduced memory footprint: No need to keep IL code in memory
• Deterministic performance: Fewer runtime surprises during critical…