Runtimes and performance

Your choice of runtime is likely determined by a variety of factors. These include the skills available in your development team and the runtimes used in existing projects, especially in migrations. This choice may also be influenced by IT policy in your organization and other external factors. Lambda is agnostic to the choice of runtime, so you are free to choose without sacrificing capabilities within the service.

Different runtimes have different performance profiles in on-demand compute services like Lambda. For example, both Python and Node.js are both fast to initialize and offer reasonable overall performance. Java is much slower to initialize but can be extremely fast once running. Go can be extremely performant for both start-up and execution. If performance is critical to your application, then profiling and comparing runtime performance is an important first step before coding applications.