Let’s talk about mvnd

15/10/2021 LuisMi Gracia

Mvnd is a tool that acts as a Maven wrapper, making Maven builds much faster (using Gradle techniques).

Its most important features include these:

mvnd comes built-in with Maven, so you don’t need to install Maven separately.
Maven builds are done inside a daemon process (mvnd from mvn + Daemon), so you don’t need to run a new JVM for each build.
A daemon instance can serve multiple consecutive requests from the mvnd client.
mvnd is a native executable built with GraalVM, so it starts faster and uses less memory compared to starting a traditional JVM.
Class-loaders containing Maven plugin classes are cached for several builds, plugin jars are read and parsed only once. SNAPSHOT versions of Maven plugins are not cached.
Native code produced by the Just-In-Time (JIT) compiler inside the JVM is also maintained. Compared to the original Maven, JIT compilation takes less time. During repeated builds, the JIT-optimised code is immediately available. This applies not only to code coming from Maven plugins and Maven Core, but also to all code coming from the JDK itself.
By default, mvnd builds its modules in parallel using multiple CPU cores. The number of cores used is given by the following formula:

Math.max(Runtime.getRuntime().availableProcessors() – 1, 1)
If the project source tree does not support parallel builds, you can pass -T1 on the command line to do the serial build.

Installation

There are several ways to install, but for this case we will use the manual method:

Download the appropriate ZIP for the platform we are working from, fromthe repository.
Unzip the files in the folder we need.
Add the bin directory to the PATH.
Optionally, we can create a «~/.m2/mvnd.properties»” and set the property «java.home», in case we don’t want to set the environment variable JAVA_HOME.
Lastly, to test if mvnd works, we will launch «mvnd –version». If all goes well, we should get something like this:

In case you get the following message in a Windows environment: «VCRUNTIME140.dll was not found» , then you will need to install the executable«vc_redist.x64.exe» from the Microsoftt support page (related issue).