diff --git a/android/composd/aidl/android/system/composd/IIsolatedCompilationService.aidl b/android/composd/aidl/android/system/composd/IIsolatedCompilationService.aidl
index dde75e1..3748899 100644
--- a/android/composd/aidl/android/system/composd/IIsolatedCompilationService.aidl
+++ b/android/composd/aidl/android/system/composd/IIsolatedCompilationService.aidl
@@ -48,5 +48,6 @@
      * callback, unless the returned ICompilationTask is cancelled. The caller should maintain
      * a reference to the ICompilationTask until compilation completes or is cancelled.
      */
-    ICompilationTask startTestCompile(ApexSource apexSource, ICompilationTaskCallback callback);
+    ICompilationTask startTestCompile(
+            ApexSource apexSource, ICompilationTaskCallback callback, String os);
 }
diff --git a/android/composd/src/instance_manager.rs b/android/composd/src/instance_manager.rs
index 9e94035..cb1f7e4 100644
--- a/android/composd/src/instance_manager.rs
+++ b/android/composd/src/instance_manager.rs
@@ -46,11 +46,12 @@
         self.start_instance(CURRENT_INSTANCE_DIR, vm_parameters)
     }
 
-    pub fn start_test_instance(&self, prefer_staged: bool) -> Result<CompOsInstance> {
+    pub fn start_test_instance(&self, prefer_staged: bool, os: &str) -> Result<CompOsInstance> {
         let mut vm_parameters = new_vm_parameters()?;
         vm_parameters.name = String::from("ComposdTest");
         vm_parameters.debug_mode = true;
         vm_parameters.prefer_staged = prefer_staged;
+        vm_parameters.os = os.to_owned();
         self.start_instance(TEST_INSTANCE_DIR, vm_parameters)
     }
 
diff --git a/android/composd/src/service.rs b/android/composd/src/service.rs
index 49cfd3a..3cc40af 100644
--- a/android/composd/src/service.rs
+++ b/android/composd/src/service.rs
@@ -60,6 +60,7 @@
         &self,
         apex_source: ApexSource,
         callback: &Strong<dyn ICompilationTaskCallback>,
+        os: &str,
     ) -> binder::Result<Strong<dyn ICompilationTask>> {
         check_permissions()?;
         let prefer_staged = match apex_source {
@@ -67,7 +68,7 @@
             ApexSource::PreferStaged => true,
             _ => unreachable!("Invalid ApexSource {:?}", apex_source),
         };
-        to_binder_result(self.do_start_test_compile(prefer_staged, callback))
+        to_binder_result(self.do_start_test_compile(prefer_staged, callback, os))
     }
 }
 
@@ -93,9 +94,12 @@
         &self,
         prefer_staged: bool,
         callback: &Strong<dyn ICompilationTaskCallback>,
+        os: &str,
     ) -> Result<Strong<dyn ICompilationTask>> {
-        let comp_os =
-            self.instance_manager.start_test_instance(prefer_staged).context("Starting CompOS")?;
+        let comp_os = self
+            .instance_manager
+            .start_test_instance(prefer_staged, os)
+            .context("Starting CompOS")?;
 
         let target_dir_name = TEST_ARTIFACTS_SUBDIR.to_owned();
         let task = OdrefreshTask::start(