diff --git a/build.gradle.kts b/build.gradle.kts
index 1e4a1936..32735170 100644
--- a/build.gradle.kts
+++ b/build.gradle.kts
@@ -17,8 +17,8 @@ subprojects {
   apply(from = "$rootDir/gradle/spotless.gradle")
   pluginManager.withPlugin("java-library") {
     configure<JavaPluginExtension> {
-      sourceCompatibility = JavaVersion.VERSION_11
-      targetCompatibility = JavaVersion.VERSION_11
+      sourceCompatibility = JavaVersion.VERSION_1_8
+      targetCompatibility = JavaVersion.VERSION_1_8
     }
 
     repositories {
diff --git a/otel-extensions/build.gradle.kts b/otel-extensions/build.gradle.kts
index 2841856f..14f17629 100644
--- a/otel-extensions/build.gradle.kts
+++ b/otel-extensions/build.gradle.kts
@@ -38,6 +38,15 @@ dependencies {
     implementation("io.opentelemetry.javaagent:opentelemetry-javaagent-extension-api")
     implementation("io.opentelemetry.instrumentation:opentelemetry-instrumentation-api")
     implementation("io.opentelemetry.javaagent:opentelemetry-javaagent-tooling") {
+        constraints {
+            implementation("io.opentelemetry.javaagent:opentelemetry-javaagent-tooling-java9") {
+                attributes {
+                    // this transitive dependency creates classes compatible with Java 9 and up, but is only referenced in safe ways for
+                    // java 8 by the javaagent-tooling dependency
+                    attribute(Attribute.of("org.gradle.jvm.version", Integer::class.java), 9 as Integer)
+                }
+            }
+        }
         exclude("io.opentelemetry.javaagent", "opentelemetry-javaagent-bootstrap")
     }
 
diff --git a/testing-common/build.gradle.kts b/testing-common/build.gradle.kts
index eb42fae4..6cb5d2e3 100644
--- a/testing-common/build.gradle.kts
+++ b/testing-common/build.gradle.kts
@@ -20,7 +20,17 @@ dependencies {
     testFixturesApi("com.squareup.okhttp3:logging-interceptor:4.9.0")
     testFixturesImplementation("io.opentelemetry:opentelemetry-exporter-logging")
     testFixturesImplementation("io.opentelemetry.javaagent:opentelemetry-javaagent-bootstrap")
-    testFixturesImplementation("io.opentelemetry.javaagent:opentelemetry-javaagent-tooling")
+    testFixturesImplementation("io.opentelemetry.javaagent:opentelemetry-javaagent-tooling") {
+        constraints {
+            testFixturesImplementation("io.opentelemetry.javaagent:opentelemetry-javaagent-tooling-java9") {
+                attributes {
+                    // this transitive dependency creates classes compatible with Java 9 and up, but is only referenced in safe ways for
+                    // java 8 by the javaagent-tooling dependency
+                    attribute(Attribute.of("org.gradle.jvm.version", Integer::class.java), 9 as Integer)
+                }
+            }
+        }
+    }
     testFixturesImplementation("io.opentelemetry.javaagent:opentelemetry-javaagent-extension-api")
     testFixturesImplementation("io.opentelemetry.instrumentation:opentelemetry-instrumentation-api")
     testFixturesImplementation("ch.qos.logback:logback-classic:1.4.6")