ForgeGradle

Step 1: Add maven repository:

groovy (build.gradle)

repositories {
    maven { url 'https://maven.covers1624.net/' }
}

kotlin (build.gradle.kts)

repositories {
    maven("https://maven.covers1624.net/")
}

Step 2: Add runtime dependency:

groovy (build.gradle)

dependencies {
    runtimeOnly 'net.covers1624:DevLogin:0.1.0.5'
}

kotlin (build.gradle.kts)

dependencies {
    runtimeOnly("net.covers1624:DevLogin:0.1.0.5")
}

Step 3: Add run configuration:

groovy (build.gradle)

runs {
    clientAuth {
        configure('client')
        mainClass = 'net.covers1624.devlogin.DevLogin'
        programArguments '--launch_target', 'net.minecraftforge.bootstrap.ForgeBootstrap'
    }
}

kotlin (build.gradle.kts)

runs {
    clientAuth {
        configure("client")
        mainClass = "net.covers1624.devlogin.DevLogin"
        programArguments.addAll("--launch_target", "net.minecraftforge.bootstrap.ForgeBootstrap")
    }
}