Graal Native Image

Published: Apr 13, 2021
Apr 2021

Graal Native Image is a technology that compiles Java code into an operating system's native binary — in the form of a statically linked executable or a shared library. A native image is optimized to reduce the memory footprint and startup time of an application. Our teams have successfully used Graal native images, executed as small Docker containers, in the serverless architecture where reducing start time matters. Although designed for use with programming languages such as Go or Rust that natively compile and require smaller binary sizes and shorter start times, Graal Native Image can be equally useful to teams that have other requirements and want to use JVM-based languages.

Graal Native Image Builder, native-image, supports JVM-based languages — such as Java, Scala, Clojure and Kotlin — and builds executables on multiple operating systems including Mac OS, Windows and multiple distributions of Linux. Since it requires a closed-world assumption, where all code is known at compile time, additional configuration is needed for features such as reflection or dynamic class loading where types can't be deduced at build time from the code alone.