diff --git a/compos/common/Android.bp b/compos/common/Android.bp
new file mode 100644
index 0000000..d8fec81
--- /dev/null
+++ b/compos/common/Android.bp
@@ -0,0 +1,24 @@
+package {
+    default_applicable_licenses: ["Android-Apache-2.0"],
+}
+
+rust_library {
+    name: "libcompos_common",
+    crate_name: "compos_common",
+    srcs: ["lib.rs"],
+    edition: "2018",
+    rustlibs: [
+        "android.system.virtualizationservice-rust",
+        "compos_aidl_interface-rust",
+        "libanyhow",
+        "libbinder_rpc_unstable_bindgen",
+        "libbinder_rs",
+        "liblog_rust",
+    ],
+    shared_libs: [
+        "libbinder_rpc_unstable",
+    ],
+    apex_available: [
+        "com.android.compos",
+    ],
+}
diff --git a/compos/common/compos_client.rs b/compos/common/compos_client.rs
new file mode 100644
index 0000000..dd8e54f
--- /dev/null
+++ b/compos/common/compos_client.rs
@@ -0,0 +1,218 @@
+/*
+ * Copyright (C) 2021 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+//! Support for starting CompOS in a VM and connecting to the service
+
+use crate::{COMPOS_APEX_ROOT, COMPOS_DATA_ROOT, COMPOS_VSOCK_PORT};
+use android_system_virtualizationservice::aidl::android::system::virtualizationservice::{
+    IVirtualMachine::IVirtualMachine,
+    IVirtualMachineCallback::{BnVirtualMachineCallback, IVirtualMachineCallback},
+    IVirtualizationService::IVirtualizationService,
+    VirtualMachineAppConfig::VirtualMachineAppConfig,
+    VirtualMachineConfig::VirtualMachineConfig,
+};
+use android_system_virtualizationservice::binder::{
+    wait_for_interface, BinderFeatures, DeathRecipient, IBinder, Interface, ParcelFileDescriptor,
+    Result as BinderResult, Strong,
+};
+use anyhow::{anyhow, bail, Context, Result};
+use binder::{
+    unstable_api::{new_spibinder, AIBinder},
+    FromIBinder,
+};
+use compos_aidl_interface::aidl::com::android::compos::ICompOsService::ICompOsService;
+use std::fs::File;
+use std::path::Path;
+use std::sync::{Arc, Condvar, Mutex};
+use std::thread;
+use std::time::Duration;
+
+/// This owns an instance of the CompOS VM.
+pub struct VmInstance {
+    #[allow(dead_code)] // Keeps the vm alive even if we don`t touch it
+    vm: Strong<dyn IVirtualMachine>,
+    cid: i32,
+}
+
+impl VmInstance {
+    /// Start a new CompOS VM instance using the specified instance image file.
+    pub fn start(instance_image: &Path) -> Result<VmInstance> {
+        let instance_image =
+            File::open(instance_image).context("Failed to open instance image file")?;
+        let instance_fd = ParcelFileDescriptor::new(instance_image);
+
+        let apex_dir = Path::new(COMPOS_APEX_ROOT);
+        let data_dir = Path::new(COMPOS_DATA_ROOT);
+
+        let apk_fd = File::open(apex_dir.join("app/CompOSPayloadApp/CompOSPayloadApp.apk"))
+            .context("Failed to open config APK file")?;
+        let apk_fd = ParcelFileDescriptor::new(apk_fd);
+
+        let idsig_fd = File::open(apex_dir.join("etc/CompOSPayloadApp.apk.idsig"))
+            .context("Failed to open config APK idsig file")?;
+        let idsig_fd = ParcelFileDescriptor::new(idsig_fd);
+
+        // TODO: Send this to stdout instead? Or specify None?
+        let log_fd = File::create(data_dir.join("vm.log")).context("Failed to create log file")?;
+        let log_fd = ParcelFileDescriptor::new(log_fd);
+
+        let config = VirtualMachineConfig::AppConfig(VirtualMachineAppConfig {
+            apk: Some(apk_fd),
+            idsig: Some(idsig_fd),
+            instanceImage: Some(instance_fd),
+            configPath: "assets/vm_config.json".to_owned(),
+            ..Default::default()
+        });
+
+        let service = wait_for_interface::<dyn IVirtualizationService>(
+            "android.system.virtualizationservice",
+        )
+        .context("Failed to find VirtualizationService")?;
+
+        let vm = service.startVm(&config, Some(&log_fd)).context("Failed to start VM")?;
+        let vm_state = Arc::new(VmStateMonitor::default());
+
+        let vm_state_clone = Arc::clone(&vm_state);
+        vm.as_binder().link_to_death(&mut DeathRecipient::new(move || {
+            vm_state_clone.set_died();
+            log::error!("VirtualizationService died");
+        }))?;
+
+        let vm_state_clone = Arc::clone(&vm_state);
+        let callback = BnVirtualMachineCallback::new_binder(
+            VmCallback(vm_state_clone),
+            BinderFeatures::default(),
+        );
+        vm.registerCallback(&callback)?;
+
+        let cid = vm_state.wait_for_start()?;
+
+        // TODO: Use onPayloadReady to avoid this
+        thread::sleep(Duration::from_secs(3));
+
+        Ok(VmInstance { vm, cid })
+    }
+
+    /// Create and return an RPC Binder connection to the Comp OS service in the VM.
+    pub fn get_service(&self) -> Result<Strong<dyn ICompOsService>> {
+        let cid = self.cid as u32;
+        // SAFETY: AIBinder returned by RpcClient has correct reference count, and the ownership
+        // can be safely taken by new_spibinder.
+        let ibinder = unsafe {
+            new_spibinder(
+                binder_rpc_unstable_bindgen::RpcClient(cid, COMPOS_VSOCK_PORT) as *mut AIBinder
+            )
+        }
+        .ok_or_else(|| anyhow!("Failed to connect to CompOS service"))?;
+
+        FromIBinder::try_from(ibinder).context("Connecting to CompOS service")
+    }
+}
+
+#[derive(Debug)]
+struct VmState {
+    has_died: bool,
+    cid: Option<i32>,
+}
+
+impl Default for VmState {
+    fn default() -> Self {
+        Self { has_died: false, cid: None }
+    }
+}
+
+#[derive(Debug)]
+struct VmStateMonitor {
+    mutex: Mutex<VmState>,
+    state_ready: Condvar,
+}
+
+impl Default for VmStateMonitor {
+    fn default() -> Self {
+        Self { mutex: Mutex::new(Default::default()), state_ready: Condvar::new() }
+    }
+}
+
+impl VmStateMonitor {
+    fn set_died(&self) {
+        let mut state = self.mutex.lock().unwrap();
+        state.has_died = true;
+        state.cid = None;
+        drop(state); // Unlock the mutex prior to notifying
+        self.state_ready.notify_all();
+    }
+
+    fn set_started(&self, cid: i32) {
+        let mut state = self.mutex.lock().unwrap();
+        if state.has_died {
+            return;
+        }
+        state.cid = Some(cid);
+        drop(state); // Unlock the mutex prior to notifying
+        self.state_ready.notify_all();
+    }
+
+    fn wait_for_start(&self) -> Result<i32> {
+        let (state, result) = self
+            .state_ready
+            .wait_timeout_while(self.mutex.lock().unwrap(), Duration::from_secs(10), |state| {
+                state.cid.is_none() && !state.has_died
+            })
+            .unwrap();
+        if result.timed_out() {
+            bail!("Timed out waiting for VM")
+        }
+        state.cid.ok_or_else(|| anyhow!("VM died"))
+    }
+}
+
+#[derive(Debug)]
+struct VmCallback(Arc<VmStateMonitor>);
+
+impl Interface for VmCallback {}
+
+impl IVirtualMachineCallback for VmCallback {
+    fn onDied(&self, cid: i32) -> BinderResult<()> {
+        self.0.set_died();
+        log::warn!("VM died, cid = {}", cid);
+        Ok(())
+    }
+
+    fn onPayloadStarted(
+        &self,
+        cid: i32,
+        _stream: Option<&binder::parcel::ParcelFileDescriptor>,
+    ) -> BinderResult<()> {
+        self.0.set_started(cid);
+        // TODO: Use the stream?
+        log::info!("VM payload started, cid = {}", cid);
+        Ok(())
+    }
+
+    fn onPayloadReady(&self, cid: i32) -> BinderResult<()> {
+        // TODO: Use this to trigger vsock connection
+        log::info!("VM payload ready, cid = {}", cid);
+        Ok(())
+    }
+
+    fn onPayloadFinished(&self, cid: i32, exit_code: i32) -> BinderResult<()> {
+        // This should probably never happen in our case, but if it does we means our VM is no
+        // longer running
+        self.0.set_died();
+        log::warn!("VM payload finished, cid = {}, exit code = {}", cid, exit_code);
+        Ok(())
+    }
+}
diff --git a/compos/common/lib.rs b/compos/common/lib.rs
new file mode 100644
index 0000000..081f086
--- /dev/null
+++ b/compos/common/lib.rs
@@ -0,0 +1,29 @@
+/*
+ * Copyright (C) 2021 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+//! Common items used by CompOS server and/or clients
+
+pub mod compos_client;
+
+/// VSock port that the CompOS server listens on for RPC binder connections. This should be out of
+/// future port range (if happens) that microdroid may reserve for system components.
+pub const COMPOS_VSOCK_PORT: u32 = 6432;
+
+/// The root directory where the CompOS APEX is mounted (read only).
+pub const COMPOS_APEX_ROOT: &str = "/apex/com.android.compos";
+
+/// The root of the  data directory available for private use by the CompOS APEX.
+pub const COMPOS_DATA_ROOT: &str = "/data/misc/apexdata/com.android.compos";