diff --git a/tuic-quinn/Cargo.toml b/tuic-quinn/Cargo.toml
index d98ceed..f990737 100644
--- a/tuic-quinn/Cargo.toml
+++ b/tuic-quinn/Cargo.toml
@@ -3,6 +3,10 @@ name = "tuic-quinn"
 version = "0.1.0"
 edition = "2021"
 
-# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
-
 [dependencies]
+async-trait = { version = "0.1.62", default-features = false }
+bytes = { version = "1.3.0", default-features = false, features = ["std"] }
+futures-util = { version = "0.3.25", default-features = false, features = ["io", "std"] }
+quinn = { version = "0.9.3", default-features = false, features = ["futures-io"] }
+thiserror = { version = "1.0.38", default-features = false }
+tuic = { path = "../tuic", default-features = false, features = ["model"] }
diff --git a/tuic-quinn/src/lib.rs b/tuic-quinn/src/lib.rs
index 7d12d9a..e9a5249 100644
--- a/tuic-quinn/src/lib.rs
+++ b/tuic-quinn/src/lib.rs
@@ -1,14 +1,159 @@
-pub fn add(left: usize, right: usize) -> usize {
-    left + right
-}
+use self::{marshal::Marshal, side::Side};
+use bytes::Bytes;
+use futures_util::{io::Cursor, AsyncRead, AsyncWrite, AsyncWriteExt};
+use quinn::{
+    Connection as QuinnConnection, ConnectionError, RecvStream, SendDatagramError, SendStream,
+};
+use std::{
+    io::Error as IoError,
+    pin::Pin,
+    task::{Context, Poll},
+};
+use thiserror::Error;
+use tuic::{
+    model::{
+        side::{Rx, Tx},
+        Connect as ConnectModel, Connection as ConnectionModel,
+    },
+    protocol::{Address, Header},
+};
 
-#[cfg(test)]
-mod tests {
-    use super::*;
+mod marshal;
+mod unmarshal;
 
-    #[test]
-    fn it_works() {
-        let result = add(2, 2);
-        assert_eq!(result, 4);
+pub mod side {
+    pub struct Client;
+    pub struct Server;
+
+    pub(super) enum Side<C, S> {
+        Client(C),
+        Server(S),
     }
 }
+
+pub struct Connection<'conn, Side> {
+    conn: &'conn QuinnConnection,
+    model: ConnectionModel<Bytes>,
+    _marker: Side,
+}
+
+impl<'conn> Connection<'conn, side::Client> {
+    pub fn new(conn: &'conn QuinnConnection) -> Self {
+        Self {
+            conn,
+            model: ConnectionModel::new(),
+            _marker: side::Client,
+        }
+    }
+
+    pub async fn connect(&self, addr: Address) -> Result<Connect, Error> {
+        let (mut send, recv) = self.conn.open_bi().await?;
+        let model = self.model.send_connect(addr);
+        model.header().marshal(&mut send).await?;
+        Ok(Connect::new(Side::Client(model), send, recv))
+    }
+
+    pub async fn packet_native(
+        &self,
+        pkt: impl AsRef<[u8]>,
+        assoc_id: u16,
+        addr: Address,
+    ) -> Result<(), Error> {
+        let Some(max_pkt_size) = self.conn.max_datagram_size() else {
+            return Err(Error::SendDatagram(SendDatagramError::Disabled));
+        };
+
+        let model = self.model.send_packet(assoc_id, addr, max_pkt_size);
+
+        for (header, frag) in model.into_fragments(pkt) {
+            let mut buf = Cursor::new(vec![0; header.len() + frag.len()]);
+            header.marshal(&mut buf).await?;
+            buf.write_all(frag).await.unwrap();
+            self.conn.send_datagram(Bytes::from(buf.into_inner()))?;
+        }
+
+        Ok(())
+    }
+
+    pub async fn packet_quic(
+        &self,
+        pkt: impl AsRef<[u8]>,
+        assoc_id: u16,
+        addr: Address,
+    ) -> Result<(), Error> {
+        let model = self.model.send_packet(assoc_id, addr, u16::MAX as usize);
+        let mut frags = model.into_fragments(pkt);
+        let (header, frag) = frags.next().unwrap();
+        assert!(frags.next().is_none());
+
+        let mut send = self.conn.open_uni().await?;
+        header.marshal(&mut send).await?;
+        AsyncWriteExt::write_all(&mut send, frag).await?;
+
+        Ok(())
+    }
+}
+
+pub struct Connect {
+    model: Side<ConnectModel<Tx>, ConnectModel<Rx>>,
+    send: SendStream,
+    recv: RecvStream,
+}
+
+impl Connect {
+    fn new(
+        model: Side<ConnectModel<Tx>, ConnectModel<Rx>>,
+        send: SendStream,
+        recv: RecvStream,
+    ) -> Self {
+        Self { model, send, recv }
+    }
+
+    pub fn addr(&self) -> &Address {
+        match &self.model {
+            Side::Client(model) => {
+                let Header::Connect(connect) = model.header() else { unreachable!() };
+                &connect.addr()
+            }
+            Side::Server(model) => model.addr(),
+        }
+    }
+}
+
+impl AsyncRead for Connect {
+    fn poll_read(
+        self: Pin<&mut Self>,
+        cx: &mut Context<'_>,
+        buf: &mut [u8],
+    ) -> Poll<Result<usize, IoError>> {
+        AsyncRead::poll_read(Pin::new(&mut self.get_mut().recv), cx, buf)
+    }
+}
+
+impl AsyncWrite for Connect {
+    fn poll_write(
+        self: Pin<&mut Self>,
+        cx: &mut Context<'_>,
+        buf: &[u8],
+    ) -> Poll<Result<usize, IoError>> {
+        AsyncWrite::poll_write(Pin::new(&mut self.get_mut().send), cx, buf)
+    }
+
+    fn poll_flush(self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<Result<(), IoError>> {
+        AsyncWrite::poll_flush(Pin::new(&mut self.get_mut().send), cx)
+    }
+
+    fn poll_close(self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<Result<(), IoError>> {
+        AsyncWrite::poll_close(Pin::new(&mut self.get_mut().send), cx)
+    }
+}
+
+#[derive(Debug, Error)]
+pub enum Error {
+    #[error(transparent)]
+    Io(#[from] IoError),
+    #[error(transparent)]
+    Connection(#[from] ConnectionError),
+    #[error(transparent)]
+    SendDatagram(#[from] SendDatagramError),
+}
diff --git a/tuic-quinn/src/marshal.rs b/tuic-quinn/src/marshal.rs
new file mode 100644
index 0000000..66c2d85
--- /dev/null
+++ b/tuic-quinn/src/marshal.rs
@@ -0,0 +1,16 @@
+use async_trait::async_trait;
+use futures_util::AsyncWrite;
+use std::io::Error as IoError;
+use tuic::protocol::Header;
+
+#[async_trait]
+pub(super) trait Marshal {
+    async fn marshal(&self, s: &mut impl AsyncWrite) -> Result<(), IoError>;
+}
+
+#[async_trait]
+impl Marshal for Header {
+    async fn marshal(&self, s: &mut impl AsyncWrite) -> Result<(), IoError> {
+        todo!()
+    }
+}
diff --git a/tuic-quinn/src/unmarshal.rs b/tuic-quinn/src/unmarshal.rs
new file mode 100644
index 0000000..c7e6e11
--- /dev/null
+++ b/tuic-quinn/src/unmarshal.rs
@@ -0,0 +1,7 @@
+use async_trait::async_trait;
+use futures_util::AsyncRead;
+
+#[async_trait]
+trait Unmarshal {
+    fn unmarshal(&self, s: &mut impl AsyncRead) -> Result<(), ()>;
+}