How can I force Gradle to use –module-path instead of -cp?

I have a relatively straightforward modular project, and I’ve already set all of the options that I’ve found in the documentation as well as in different answers or articles such as How to force gradle to add dependencies to the module path instead of the class path in eclipse? and others.

I’m getting a module not found exception:

java.lang.module.FindException: Module gdx.backend.lwjgl not found, required by com.myproject.client

I only get this exception when running my application through gradle’s application:run task. When I run it in IntelliJ or using the runtime image generated by the Badass JLink plugin, everything runs fine. After hours of debugging and building command lines by hand I was able to figure out that the difference between a correctly started program and what gradle does, is that everything else starts the program using the –module-path option while Gradle INSISTS on producing the following command line, no matter what I do in my build.gradle files:

Starting process 'command 'C:Toolsjavabinjava.exe''. Working directory: C:repospv-coremasterpv-client Command: C:Toolsjavabinjava.exe -Dfile.encoding=windows-1252 -Duser.country=FR -Duser.language=fr -Duser.variant -cp C:Usersaccou.gradlecachesmodules-2files-2.1com.badlogicgames.gdxgdx-backend-lwjgl1.9.113c094feb74e2aef14e30e988326612ee75387c8fgdx-backend-lwjgl-1.9.11.jar;[...] --module com.myproject.client/com.myproject.client.ClientStarter
Successfully started process 'command 'C:Toolsjavabinjava.exe''
Error occurred during initialization of boot layer
java.lang.module.FindException: Module gdx not found, required by com.myproject.client

My gradle files contain the following:

Root file:

subprojects {
    apply plugin: "java"

    java {
        modularity.inferModulePath = true
    }

    targetCompatibility = '11'
    sourceCompatibility = '11'

    repositories {
        mavenLocal()
        mavenCentral()
        maven { url "https://plugins.gradle.org/m2/" }
        maven { url "https://oss.sonatype.org/content/repositories/snapshots/" }
        jcenter()
        google()
    }

    test {
        useJUnitPlatform()

        testLogging {
            events 'PASSED', 'FAILED', 'SKIPPED'
        }
    }

    dependencies {
        testImplementation 'org.junit.jupiter:junit-jupiter-api:5.3.1'
        testImplementation 'org.junit.jupiter:junit-jupiter-params:5.3.1'
        testRuntimeOnly 'org.junit.jupiter:junit-jupiter-engine:5.3.1'
    }

    version = '0.0.1'

    ext {
        appName = 'MyProject'
        gdxVersion = '1.9.11'
        box2DLightsVersion = '1.4'
        aiVersion = '1.8.0'
        artemisVersion = '2.3.0'
        junitVersion = '5.4.2'
        slf4jVersion = '1.8.0-beta2'
    }
}

project(':pv-core') {
    dependencies {
    }
}

Client project (application):

plugins {
    id 'org.beryx.jlink' version '2.22.3'
    id 'application'
}

jlink {
    options = ['--strip-debug', '--compress', '2', '--no-header-files', '--no-man-pages']
    launcher{
        name = 'hello'
        jvmArgs = ['-Dlog4j.configurationFile=./log4j2.xml']
    }
}

ext.moduleName = 'com.myproject.client'
group = 'com.myproject.client'
//mainClassName = 'com.myproject.client.PVClientStarter'

application {
    mainModule = 'com.myproject.client'
    mainClass = 'com.myproject.client.ClientStarter'
}
apply plugin: 'java-library'

dependencies {
    api "com.badlogicgames.gdx:gdx:$gdxVersion"
    api "com.badlogicgames.gdx:gdx-backend-lwjgl:$gdxVersion"
    api "com.badlogicgames.gdx:gdx-platform:$gdxVersion:natives-desktop"
    api "com.esotericsoftware.spine:spine-libgdx:3.6.53.1"
    api "com.underwaterapps.overlap2druntime:overlap2d-runtime-libgdx:0.1.0"
    api "com.kotcrab.vis:vis-ui:1.3.0"
    api "net.dermetfan.libgdx-utils:libgdx-utils:0.13.4"
    //api "de.tomgrill.gdxfacebook:gdx-facebook-core:1.4.1"
    //api "de.tomgrill.gdxdialogs:gdx-dialogs-core:1.2.5"
    api "com.github.czyzby:gdx-kiwi:1.9.1.9.6"
    api "com.github.czyzby:gdx-lml:1.9.1.9.6"
    api "com.github.czyzby:gdx-lml-vis:1.9.1.9.6"
    api "de.golfgl.gdxgamesvcs:gdx-gamesvcs-core:1.0.2"
    compile "com.badlogicgames.gdx:gdx-ai:$aiVersion"
    compile "com.badlogicgames.gdx:gdx-controllers:$gdxVersion"
    //compile "com.esotericsoftware:kryo:5.0.0"
    compile "kryonet:kryonet:2.21"
    testCompile 'org.testng:testng:7.3.0'
}

test {
    useTestNG()
    //testLogging.showStandardStreams = true
    testLogging {
        events "passed", "skipped", "failed"
    }
}

compileJava {
    inputs.property("moduleName", moduleName)
    doFirst {
        options.compilerArgs += [
                '--module-path', classpath.asPath
        ]
        classpath = files()
    }
}

Any idea as to how I can possibly (FINALLY) tell gradle to go with –module-path rather than -cp ?!