diff --git a/microdroid_manager/src/main.rs b/microdroid_manager/src/main.rs
new file mode 100644
index 0000000..4f87a40
--- /dev/null
+++ b/microdroid_manager/src/main.rs
@@ -0,0 +1,51 @@
+// Copyright 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.
+
+//! Microdroid Manager
+
+mod payload_config;
+mod signature;
+
+use android_logger::Config;
+use log::{info, Level};
+use payload_config::{Task, VmPayloadConfig};
+use std::io;
+use std::process::Command;
+
+const LOG_TAG: &str = "MicrodroidManager";
+
+fn main() -> io::Result<()> {
+    android_logger::init_once(Config::default().with_tag(LOG_TAG).with_min_level(Level::Debug));
+
+    info!("started.");
+
+    let signature = signature::load()?;
+    if !signature.payload_config_path.is_empty() {
+        let config = VmPayloadConfig::load_from(&signature.payload_config_path)?;
+        if let Some(main_task) = &config.task {
+            exec(main_task)?;
+        }
+    }
+
+    Ok(())
+}
+
+/// executes a task
+/// TODO(jooyung): fork a child process
+fn exec(task: &Task) -> io::Result<()> {
+    info!("executing main task {} {:?}...", task.command, task.args);
+    let exit_status = Command::new(&task.command).args(&task.args).status()?;
+    info!("exit with {}", &exit_status);
+    Ok(())
+}
diff --git a/microdroid_manager/src/payload_config.rs b/microdroid_manager/src/payload_config.rs
new file mode 100644
index 0000000..1dd6d92
--- /dev/null
+++ b/microdroid_manager/src/payload_config.rs
@@ -0,0 +1,41 @@
+// Copyright 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.
+
+//! VM Payload Config
+
+use log::info;
+use serde::{Deserialize, Serialize};
+use std::fs::File;
+use std::io;
+
+#[derive(Clone, Debug, Deserialize, Eq, PartialEq, Serialize)]
+pub struct VmPayloadConfig {
+    #[serde(default)]
+    pub task: Option<Task>,
+}
+
+#[derive(Clone, Debug, Deserialize, Eq, PartialEq, Serialize)]
+pub struct Task {
+    pub command: String,
+    #[serde(default)]
+    pub args: Vec<String>,
+}
+
+impl VmPayloadConfig {
+    pub fn load_from(path: &str) -> io::Result<VmPayloadConfig> {
+        info!("loading config from {}...", path);
+        let file = File::open(path)?;
+        Ok(serde_json::from_reader(file)?)
+    }
+}
diff --git a/microdroid_manager/src/signature.rs b/microdroid_manager/src/signature.rs
new file mode 100644
index 0000000..4f06885
--- /dev/null
+++ b/microdroid_manager/src/signature.rs
@@ -0,0 +1,40 @@
+// Copyright 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.
+
+//! MicrodroidSignature from /dev/block/by-name/signature
+//! TODO(jooyung): migrate to "metadata" partition
+
+use log::info;
+use microdroid_signature::microdroid_signature::MicrodroidSignature;
+use protobuf::Message;
+use std::fs::File;
+use std::io;
+use std::io::Read;
+
+const SIGNATURE_PATH: &str = "/dev/block/by-name/signature";
+
+/// loads microdroid_signature from /dev/block/by-name/signature
+pub fn load() -> io::Result<MicrodroidSignature> {
+    info!("loading signature...");
+
+    let mut f = File::open(SIGNATURE_PATH)?;
+    // signature partition is
+    //  4 bytes : size(N) in big endian
+    //  N bytes : message for MicrodroidSignature
+    let mut buf = [0u8; 4];
+    f.read_exact(&mut buf)?;
+    let size = i32::from_be_bytes(buf);
+
+    Ok(MicrodroidSignature::parse_from_reader(&mut f.take(size as u64))?)
+}