diff --git a/tools/aegis4j/build.gradle b/tools/aegis4j/build.gradle
index 908e4980d0..b70ae385c2 100644
--- a/tools/aegis4j/build.gradle
+++ b/tools/aegis4j/build.gradle
@@ -42,8 +42,6 @@ compileTestJava.options.encoding = 'UTF-8'
 javadoc.options.encoding = 'UTF-8'
 
 java {
-    //withJavadocJar()
-    //withSourcesJar()
 }
 
 test {
@@ -83,51 +81,3 @@ shadowJar {
 tasks.build.dependsOn tasks.shadowJar
 tasks.test.dependsOn tasks.shadowJar
 
-/*
-publishing {
-    publications {
-        mavenJava(MavenPublication) { publication ->
-            project.shadow.component(publication)
-            artifact sourcesJar
-            artifact javadocJar
-            pom {
-                groupId = 'net.gredler'
-                name = 'aegis4j'
-                url = 'https://github.com/gredler/aegis4j'
-                description = 'A Java agent which disables dangerous rarely-used runtime features.'
-                licenses {
-                    license {
-                        name = 'The Apache License, Version 2.0'
-                        url = 'http://www.apache.org/licenses/LICENSE-2.0.txt'
-                    }
-                }
-                developers {
-                    developer {
-                        id = 'gredler'
-                        name = 'Daniel Gredler'
-                        email = 'daniel.gredler@gmail.com'
-                    }
-                }
-                scm {
-                    url = 'https://github.com/gredler/aegis4j'
-                    connection = 'scm:git:git://github.com/gredler/aegis4j.git'
-                    developerConnection = 'scm:git:ssh:git@github.com:gredler/aegis4j.git'
-                }
-            }
-        }
-    }
-    repositories {
-        maven {
-            url = 'https://oss.sonatype.org/service/local/staging/deploy/maven2/'
-            credentials {
-                username = project.hasProperty('ossrhUsername') ? ossrhUsername : 'unknown'
-                password = project.hasProperty('ossrhPassword') ? ossrhPassword : 'unknown'
-            }
-        }
-    }
-}
-
-signing {
-    sign publishing.publications.mavenJava
-}
-*/
diff --git a/tools/aegis4j/src/main/java/net/gredler/aegis4j/AegisAgent.java b/tools/aegis4j/src/main/java/net/gredler/aegis4j/AegisAgent.java
index 48d13b8e91..ff9fbc95eb 100644
--- a/tools/aegis4j/src/main/java/net/gredler/aegis4j/AegisAgent.java
+++ b/tools/aegis4j/src/main/java/net/gredler/aegis4j/AegisAgent.java
@@ -36,6 +36,14 @@ public final class AegisAgent {
      */
     public static void premain(String args, Instrumentation instr) {
         instrumentation = instr;
+        String argsProperty = System.getProperty("aegis4j.additional.args");
+        if (argsProperty != null) {
+            if (args == null || args.trim().isEmpty()) {
+                args = argsProperty;
+            } else {
+                args += ";" + argsProperty;
+            }
+        }
         try {
             boolean started = false;
             Properties props = null;
diff --git a/tools/aegis4j/src/test/java/net/gredler/aegis4j/AegisAgentSystemPropertyTest.java b/tools/aegis4j/src/test/java/net/gredler/aegis4j/AegisAgentSystemPropertyTest.java
new file mode 100644
index 0000000000..2a357c3ed2
--- /dev/null
+++ b/tools/aegis4j/src/test/java/net/gredler/aegis4j/AegisAgentSystemPropertyTest.java
@@ -0,0 +1,40 @@
+/* Copyright (c) 2022, Daniel Gredler. All rights reserved. */
+
+package net.gredler.aegis4j;
+
+import org.junit.jupiter.api.AfterAll;
+import org.junit.jupiter.api.Test;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+
+/**
+ * Tests {@link AegisAgent} monitoring via system properties.
+ */
+public class AegisAgentSystemPropertyTest {
+    @AfterAll
+    public static void uninstallAgent() throws Exception {
+        System.clearProperty("aegis4j.additional.args");
+        TestUtils.installAgent("unblock=serialization");
+    }
+
+    @Test
+    public void testSystemPropertyWithNullExistingArgs() throws Exception {
+        System.setProperty("aegis4j.additional.args", "unblock=jndi,rmi,scripting");
+        TestUtils.installAgent(null);
+        assertEquals("serialization,process,httpserver", System.getProperty("aegis4j.blocked.features"));
+    }
+
+    @Test
+    public void testSystemPropertyWithEmptyExistingArgs() throws Exception {
+        System.setProperty("aegis4j.additional.args", "unblock=jndi,rmi,scripting");
+        TestUtils.installAgent("");
+        assertEquals("serialization,process,httpserver", System.getProperty("aegis4j.blocked.features"));
+    }
+
+    @Test
+    public void testSystemPropertyWithNonEmptyExistingArgs() throws Exception {
+        System.setProperty("aegis4j.additional.args", "unblock=jndi,rmi,scripting");
+        TestUtils.installAgent("path=../resources/main/net/gredler/aegis4j/mods.properties");
+        assertEquals("serialization,process,httpserver", System.getProperty("aegis4j.blocked.features"));
+    }
+}