From 9b70a6141e21e40ffcf74e435f09a0a23492ecbc Mon Sep 17 00:00:00 2001
From: Thomas Eizinger <thomas@eizinger.io>
Date: Mon, 24 Oct 2022 12:38:47 +1100
Subject: [PATCH 1/4] Deprecate development transports

These create circular dependencies to the root libp2p crate in tests.
---
 CHANGELOG.md                                        |  2 ++
 examples/chat.rs                                    | 11 ++++++++---
 examples/distributed-key-value-store.rs             | 13 +++++++++----
 examples/file-sharing.rs                            | 11 +++++++++--
 examples/gossipsub-chat.rs                          | 12 ++++++++++--
 examples/ipfs-kad.rs                                | 13 +++++++++----
 examples/mdns-passive-discovery.rs                  | 10 ++++++++--
 examples/ping.rs                                    | 11 +++++++++--
 misc/metrics/examples/metrics/main.rs               | 11 +++++++++--
 protocols/autonat/examples/autonat_client.rs        | 11 ++++++++++-
 protocols/autonat/examples/autonat_server.rs        | 11 ++++++++++-
 protocols/autonat/tests/test_client.rs              | 12 +++++++++---
 protocols/autonat/tests/test_server.rs              | 12 +++++++++---
 protocols/identify/examples/identify.rs             | 11 +++++++++--
 protocols/mdns/tests/use-async-std.rs               | 10 ++++++++--
 protocols/mdns/tests/use-tokio.rs                   | 10 ++++++++--
 protocols/rendezvous/examples/discover.rs           | 11 +++++++++--
 protocols/rendezvous/examples/register.rs           | 11 +++++++++--
 .../rendezvous/examples/register_with_identify.rs   |  8 ++++++--
 protocols/rendezvous/examples/rendezvous_point.rs   |  8 ++++++--
 src/lib.rs                                          |  8 ++++++++
 21 files changed, 174 insertions(+), 43 deletions(-)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 4842ad21752..906925114b6 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -48,8 +48,10 @@
 
 - Remove deprecated features: `tcp-tokio`, `mdns-tokio`, `dns-tokio`, `tcp-async-io`, `mdns-async-io`, `dns-async-std`.
   See [PR 3001].
+- Deprecate `development_transport` and `tokio_development_transport`. See [PR XXXX].
 
 [PR 3001]: https://github.com/libp2p/rust-libp2p/pull/3001
+[PR XXXX]: https://github.com/libp2p/rust-libp2p/pull/XXXX
 
 # 0.49.0
 
diff --git a/examples/chat.rs b/examples/chat.rs
index e5368b49e80..11e1cb4ef78 100644
--- a/examples/chat.rs
+++ b/examples/chat.rs
@@ -55,11 +55,13 @@ use futures::{
     select,
 };
 use libp2p::{
+    core::{upgrade::Version, Transport},
     floodsub::{self, Floodsub, FloodsubEvent},
     identity,
     mdns::{Mdns, MdnsConfig, MdnsEvent},
+    noise,
     swarm::SwarmEvent,
-    Multiaddr, NetworkBehaviour, PeerId, Swarm,
+    tcp, yamux, Multiaddr, NetworkBehaviour, PeerId, Swarm,
 };
 use std::error::Error;
 
@@ -72,8 +74,11 @@ async fn main() -> Result<(), Box<dyn Error>> {
     let local_peer_id = PeerId::from(local_key.public());
     println!("Local peer id: {:?}", local_peer_id);
 
-    // Set up an encrypted DNS-enabled TCP Transport over the Mplex and Yamux protocols
-    let transport = libp2p::development_transport(local_key).await?;
+    let transport = tcp::TcpTransport::default()
+        .upgrade(Version::V1)
+        .authenticate(noise::NoiseAuthenticated::xx(&local_key)?)
+        .multiplex(yamux::YamuxConfig::default())
+        .boxed();
 
     // Create a Floodsub topic
     let floodsub_topic = floodsub::Topic::new("chat");
diff --git a/examples/distributed-key-value-store.rs b/examples/distributed-key-value-store.rs
index de02ddf81be..13ea33761a1 100644
--- a/examples/distributed-key-value-store.rs
+++ b/examples/distributed-key-value-store.rs
@@ -48,10 +48,12 @@ use libp2p::kad::{
     Quorum, Record,
 };
 use libp2p::{
-    development_transport, identity,
+    core::{upgrade::Version, Transport},
+    identity,
     mdns::{Mdns, MdnsConfig, MdnsEvent},
+    noise,
     swarm::SwarmEvent,
-    NetworkBehaviour, PeerId, Swarm,
+    tcp, yamux, NetworkBehaviour, PeerId, Swarm,
 };
 use std::error::Error;
 
@@ -63,8 +65,11 @@ async fn main() -> Result<(), Box<dyn Error>> {
     let local_key = identity::Keypair::generate_ed25519();
     let local_peer_id = PeerId::from(local_key.public());
 
-    // Set up a an encrypted DNS-enabled TCP Transport over the Mplex protocol.
-    let transport = development_transport(local_key).await?;
+    let transport = tcp::TcpTransport::default()
+        .upgrade(Version::V1)
+        .authenticate(noise::NoiseAuthenticated::xx(&local_key)?)
+        .multiplex(yamux::YamuxConfig::default())
+        .boxed();
 
     // We create a custom network behaviour that combines Kademlia and mDNS.
     #[derive(NetworkBehaviour)]
diff --git a/examples/file-sharing.rs b/examples/file-sharing.rs
index 4e3cad3f187..76d28e5ee02 100644
--- a/examples/file-sharing.rs
+++ b/examples/file-sharing.rs
@@ -81,8 +81,11 @@ use async_std::io;
 use async_std::task::spawn;
 use clap::Parser;
 use futures::prelude::*;
-use libp2p::core::{Multiaddr, PeerId};
+use libp2p::core::{upgrade::Version, Multiaddr, PeerId, Transport};
 use libp2p::multiaddr::Protocol;
+use libp2p::noise;
+use libp2p::tcp;
+use libp2p::yamux;
 use std::error::Error;
 use std::io::Write;
 use std::path::PathBuf;
@@ -252,7 +255,11 @@ mod network {
         // Build the Swarm, connecting the lower layer transport logic with the
         // higher layer network behaviour logic.
         let swarm = SwarmBuilder::new(
-            libp2p::development_transport(id_keys).await?,
+            tcp::TcpTransport::default()
+                .upgrade(Version::V1)
+                .authenticate(noise::NoiseAuthenticated::xx(&id_keys)?)
+                .multiplex(yamux::YamuxConfig::default())
+                .boxed(),
             ComposedBehaviour {
                 kademlia: Kademlia::new(peer_id, MemoryStore::new(peer_id)),
                 request_response: RequestResponse::new(
diff --git a/examples/gossipsub-chat.rs b/examples/gossipsub-chat.rs
index 807209324f6..b67c40da51b 100644
--- a/examples/gossipsub-chat.rs
+++ b/examples/gossipsub-chat.rs
@@ -49,10 +49,15 @@
 use async_std::io;
 use env_logger::{Builder, Env};
 use futures::{prelude::*, select};
+use libp2p::core::upgrade::Version;
+use libp2p::core::Transport;
 use libp2p::gossipsub::MessageId;
 use libp2p::gossipsub::{
     GossipsubEvent, GossipsubMessage, IdentTopic as Topic, MessageAuthenticity, ValidationMode,
 };
+use libp2p::noise;
+use libp2p::tcp;
+use libp2p::yamux;
 use libp2p::{gossipsub, identity, swarm::SwarmEvent, Multiaddr, PeerId};
 use std::collections::hash_map::DefaultHasher;
 use std::error::Error;
@@ -68,8 +73,11 @@ async fn main() -> Result<(), Box<dyn Error>> {
     let local_peer_id = PeerId::from(local_key.public());
     println!("Local peer id: {:?}", local_peer_id);
 
-    // Set up an encrypted TCP Transport over the Mplex and Yamux protocols
-    let transport = libp2p::development_transport(local_key.clone()).await?;
+    let transport = tcp::TcpTransport::default()
+        .upgrade(Version::V1)
+        .authenticate(noise::NoiseAuthenticated::xx(&local_key).unwrap())
+        .multiplex(yamux::YamuxConfig::default())
+        .boxed();
 
     // Create a Gossipsub topic
     let topic = Topic::new("test-net");
diff --git a/examples/ipfs-kad.rs b/examples/ipfs-kad.rs
index a36ed97737b..b09b633e98d 100644
--- a/examples/ipfs-kad.rs
+++ b/examples/ipfs-kad.rs
@@ -28,9 +28,11 @@ use futures::StreamExt;
 use libp2p::kad::record::store::MemoryStore;
 use libp2p::kad::{GetClosestPeersError, Kademlia, KademliaConfig, KademliaEvent, QueryResult};
 use libp2p::{
-    development_transport, identity,
+    core::upgrade::Version,
+    core::Transport,
+    identity, noise,
     swarm::{Swarm, SwarmEvent},
-    Multiaddr, PeerId,
+    tcp, yamux, Multiaddr, PeerId,
 };
 use std::{env, error::Error, str::FromStr, time::Duration};
 
@@ -49,8 +51,11 @@ async fn main() -> Result<(), Box<dyn Error>> {
     let local_key = identity::Keypair::generate_ed25519();
     let local_peer_id = PeerId::from(local_key.public());
 
-    // Set up a an encrypted DNS-enabled TCP Transport over the Mplex protocol
-    let transport = development_transport(local_key).await?;
+    let transport = tcp::TcpTransport::default()
+        .upgrade(Version::V1)
+        .authenticate(noise::NoiseAuthenticated::xx(&local_key)?)
+        .multiplex(yamux::YamuxConfig::default())
+        .boxed();
 
     // Create a swarm to manage peers and events.
     let mut swarm = {
diff --git a/examples/mdns-passive-discovery.rs b/examples/mdns-passive-discovery.rs
index 9ac7e1a45a0..9b66673e7f4 100644
--- a/examples/mdns-passive-discovery.rs
+++ b/examples/mdns-passive-discovery.rs
@@ -20,10 +20,12 @@
 
 use futures::StreamExt;
 use libp2p::{
+    core::{upgrade::Version, Transport},
     identity,
     mdns::{Mdns, MdnsConfig, MdnsEvent},
+    noise,
     swarm::{Swarm, SwarmEvent},
-    PeerId,
+    tcp, yamux, PeerId,
 };
 use std::error::Error;
 
@@ -37,7 +39,11 @@ async fn main() -> Result<(), Box<dyn Error>> {
     println!("Local peer id: {:?}", peer_id);
 
     // Create a transport.
-    let transport = libp2p::development_transport(id_keys).await?;
+    let transport = tcp::TcpTransport::default()
+        .upgrade(Version::V1)
+        .authenticate(noise::NoiseAuthenticated::xx(&id_keys)?)
+        .multiplex(yamux::YamuxConfig::default())
+        .boxed();
 
     // Create an MDNS network behaviour.
     let behaviour = Mdns::new(MdnsConfig::default())?;
diff --git a/examples/ping.rs b/examples/ping.rs
index 9be23419e40..c5504706cc4 100644
--- a/examples/ping.rs
+++ b/examples/ping.rs
@@ -42,7 +42,10 @@
 
 use futures::prelude::*;
 use libp2p::swarm::{Swarm, SwarmEvent};
-use libp2p::{identity, ping, Multiaddr, NetworkBehaviour, PeerId};
+use libp2p::{
+    core::{upgrade::Version, Transport},
+    identity, noise, ping, tcp, yamux, Multiaddr, NetworkBehaviour, PeerId,
+};
 use libp2p_swarm::keep_alive;
 use std::error::Error;
 
@@ -52,7 +55,11 @@ async fn main() -> Result<(), Box<dyn Error>> {
     let local_peer_id = PeerId::from(local_key.public());
     println!("Local peer id: {:?}", local_peer_id);
 
-    let transport = libp2p::development_transport(local_key).await?;
+    let transport = tcp::TcpTransport::default()
+        .upgrade(Version::V1)
+        .authenticate(noise::NoiseAuthenticated::xx(&local_key)?)
+        .multiplex(yamux::YamuxConfig::default())
+        .boxed();
 
     let mut swarm = Swarm::new(transport, Behaviour::default(), local_peer_id);
 
diff --git a/misc/metrics/examples/metrics/main.rs b/misc/metrics/examples/metrics/main.rs
index 0307e32dc1e..c86d9eeea5d 100644
--- a/misc/metrics/examples/metrics/main.rs
+++ b/misc/metrics/examples/metrics/main.rs
@@ -54,7 +54,10 @@ use futures::stream::StreamExt;
 use libp2p::core::Multiaddr;
 use libp2p::metrics::{Metrics, Recorder};
 use libp2p::swarm::SwarmEvent;
-use libp2p::{identity, ping, NetworkBehaviour, PeerId, Swarm};
+use libp2p::{
+    core::{upgrade::Version, Transport},
+    identity, noise, ping, tcp, yamux, NetworkBehaviour, PeerId, Swarm,
+};
 use libp2p_swarm::keep_alive;
 use log::info;
 use prometheus_client::registry::Registry;
@@ -71,7 +74,11 @@ fn main() -> Result<(), Box<dyn Error>> {
     info!("Local peer id: {:?}", local_peer_id);
 
     let mut swarm = Swarm::new(
-        block_on(libp2p::development_transport(local_key))?,
+        tcp::TcpTransport::default()
+            .upgrade(Version::V1)
+            .authenticate(noise::NoiseAuthenticated::xx(&local_key)?)
+            .multiplex(yamux::YamuxConfig::default())
+            .boxed(),
         Behaviour::default(),
         local_peer_id,
     );
diff --git a/protocols/autonat/examples/autonat_client.rs b/protocols/autonat/examples/autonat_client.rs
index c90a5c55060..de0e7a4cb9b 100644
--- a/protocols/autonat/examples/autonat_client.rs
+++ b/protocols/autonat/examples/autonat_client.rs
@@ -32,10 +32,15 @@
 use clap::Parser;
 use futures::prelude::*;
 use libp2p::autonat;
+use libp2p::core::Transport;
 use libp2p::identify;
 use libp2p::multiaddr::Protocol;
+use libp2p::noise;
 use libp2p::swarm::{Swarm, SwarmEvent};
+use libp2p::tcp;
+use libp2p::yamux;
 use libp2p::{identity, Multiaddr, NetworkBehaviour, PeerId};
+use libp2p_core::upgrade::Version;
 use std::error::Error;
 use std::net::Ipv4Addr;
 use std::time::Duration;
@@ -63,7 +68,11 @@ async fn main() -> Result<(), Box<dyn Error>> {
     let local_peer_id = PeerId::from(local_key.public());
     println!("Local peer id: {:?}", local_peer_id);
 
-    let transport = libp2p::development_transport(local_key.clone()).await?;
+    let transport = tcp::TcpTransport::default()
+        .upgrade(Version::V1)
+        .authenticate(noise::NoiseAuthenticated::xx(&local_key)?)
+        .multiplex(yamux::YamuxConfig::default())
+        .boxed();
 
     let behaviour = Behaviour::new(local_key.public());
 
diff --git a/protocols/autonat/examples/autonat_server.rs b/protocols/autonat/examples/autonat_server.rs
index 7bb79383710..88b33d0ca20 100644
--- a/protocols/autonat/examples/autonat_server.rs
+++ b/protocols/autonat/examples/autonat_server.rs
@@ -31,8 +31,13 @@ use futures::prelude::*;
 use libp2p::autonat;
 use libp2p::identify;
 use libp2p::multiaddr::Protocol;
+use libp2p::noise;
 use libp2p::swarm::{Swarm, SwarmEvent};
+use libp2p::tcp;
+use libp2p::yamux;
 use libp2p::{identity, Multiaddr, NetworkBehaviour, PeerId};
+use libp2p_core::upgrade::Version;
+use libp2p_core::Transport;
 use std::error::Error;
 use std::net::Ipv4Addr;
 
@@ -53,7 +58,11 @@ async fn main() -> Result<(), Box<dyn Error>> {
     let local_peer_id = PeerId::from(local_key.public());
     println!("Local peer id: {:?}", local_peer_id);
 
-    let transport = libp2p::development_transport(local_key.clone()).await?;
+    let transport = tcp::TcpTransport::default()
+        .upgrade(Version::V1)
+        .authenticate(noise::NoiseAuthenticated::xx(&local_key)?)
+        .multiplex(yamux::YamuxConfig::default())
+        .boxed();
 
     let behaviour = Behaviour::new(local_key.public());
 
diff --git a/protocols/autonat/tests/test_client.rs b/protocols/autonat/tests/test_client.rs
index 420bcf99829..70af148301a 100644
--- a/protocols/autonat/tests/test_client.rs
+++ b/protocols/autonat/tests/test_client.rs
@@ -21,10 +21,12 @@
 use futures::{channel::oneshot, Future, FutureExt, StreamExt};
 use futures_timer::Delay;
 use libp2p::{
-    development_transport,
+    core::upgrade::Version,
+    core::Transport,
     identity::Keypair,
+    noise,
     swarm::{AddressScore, Swarm, SwarmEvent},
-    Multiaddr, PeerId,
+    tcp, yamux, Multiaddr, PeerId,
 };
 use libp2p_autonat::{
     Behaviour, Config, Event, NatStatus, OutboundProbeError, OutboundProbeEvent, ResponseError,
@@ -38,7 +40,11 @@ const TEST_REFRESH_INTERVAL: Duration = Duration::from_secs(2);
 async fn init_swarm(config: Config) -> Swarm<Behaviour> {
     let keypair = Keypair::generate_ed25519();
     let local_id = PeerId::from_public_key(&keypair.public());
-    let transport = development_transport(keypair).await.unwrap();
+    let transport = tcp::TcpTransport::default()
+        .upgrade(Version::V1)
+        .authenticate(noise::NoiseAuthenticated::xx(&keypair).unwrap())
+        .multiplex(yamux::YamuxConfig::default())
+        .boxed();
     let behaviour = Behaviour::new(local_id, config);
     Swarm::new(transport, behaviour, local_id)
 }
diff --git a/protocols/autonat/tests/test_server.rs b/protocols/autonat/tests/test_server.rs
index b45ae7ecafc..c59f4c111e6 100644
--- a/protocols/autonat/tests/test_server.rs
+++ b/protocols/autonat/tests/test_server.rs
@@ -23,11 +23,13 @@ use futures_timer::Delay;
 use libp2p::core::{ConnectedPoint, Endpoint};
 use libp2p::swarm::DialError;
 use libp2p::{
-    development_transport,
+    core::upgrade::Version,
+    core::Transport,
     identity::Keypair,
     multiaddr::Protocol,
+    noise,
     swarm::{AddressScore, Swarm, SwarmEvent},
-    Multiaddr, PeerId,
+    tcp, yamux, Multiaddr, PeerId,
 };
 use libp2p_autonat::{
     Behaviour, Config, Event, InboundProbeError, InboundProbeEvent, ResponseError,
@@ -37,7 +39,11 @@ use std::{num::NonZeroU32, time::Duration};
 async fn init_swarm(config: Config) -> Swarm<Behaviour> {
     let keypair = Keypair::generate_ed25519();
     let local_id = PeerId::from_public_key(&keypair.public());
-    let transport = development_transport(keypair).await.unwrap();
+    let transport = tcp::TcpTransport::default()
+        .upgrade(Version::V1)
+        .authenticate(noise::NoiseAuthenticated::xx(&keypair).unwrap())
+        .multiplex(yamux::YamuxConfig::default())
+        .boxed();
     let behaviour = Behaviour::new(local_id, config);
     Swarm::new(transport, behaviour, local_id)
 }
diff --git a/protocols/identify/examples/identify.rs b/protocols/identify/examples/identify.rs
index b02eb1c9ebf..2196c4b0f7e 100644
--- a/protocols/identify/examples/identify.rs
+++ b/protocols/identify/examples/identify.rs
@@ -37,7 +37,10 @@
 //! and will send each other identify info which is then printed to the console.
 
 use futures::prelude::*;
-use libp2p::{identify, identity, Multiaddr, PeerId};
+use libp2p::{
+    core::{upgrade::Version, Transport},
+    identify, identity, noise, tcp, yamux, Multiaddr, PeerId,
+};
 use libp2p_swarm::{Swarm, SwarmEvent};
 use std::error::Error;
 
@@ -47,7 +50,11 @@ async fn main() -> Result<(), Box<dyn Error>> {
     let local_peer_id = PeerId::from(local_key.public());
     println!("Local peer id: {:?}", local_peer_id);
 
-    let transport = libp2p::development_transport(local_key.clone()).await?;
+    let transport = tcp::TcpTransport::default()
+        .upgrade(Version::V1)
+        .authenticate(noise::NoiseAuthenticated::xx(&local_key)?)
+        .multiplex(yamux::YamuxConfig::default())
+        .boxed();
 
     // Create a identify network behaviour.
     let behaviour = identify::Behaviour::new(identify::Config::new(
diff --git a/protocols/mdns/tests/use-async-std.rs b/protocols/mdns/tests/use-async-std.rs
index 2ddb36355be..1a98bddc27c 100644
--- a/protocols/mdns/tests/use-async-std.rs
+++ b/protocols/mdns/tests/use-async-std.rs
@@ -20,10 +20,12 @@
 
 use futures::StreamExt;
 use libp2p::{
+    core::{upgrade::Version, Transport},
     identity,
     mdns::{Mdns, MdnsConfig, MdnsEvent},
+    noise,
     swarm::{Swarm, SwarmEvent},
-    PeerId,
+    tcp, yamux, PeerId,
 };
 use std::error::Error;
 use std::time::Duration;
@@ -60,7 +62,11 @@ async fn test_expired_async_std() -> Result<(), Box<dyn Error>> {
 async fn create_swarm(config: MdnsConfig) -> Result<Swarm<Mdns>, Box<dyn Error>> {
     let id_keys = identity::Keypair::generate_ed25519();
     let peer_id = PeerId::from(id_keys.public());
-    let transport = libp2p::development_transport(id_keys).await?;
+    let transport = tcp::TcpTransport::default()
+        .upgrade(Version::V1)
+        .authenticate(noise::NoiseAuthenticated::xx(&id_keys)?)
+        .multiplex(yamux::YamuxConfig::default())
+        .boxed();
     let behaviour = Mdns::new(config)?;
     let mut swarm = Swarm::new(transport, behaviour, peer_id);
     swarm.listen_on("/ip4/0.0.0.0/tcp/0".parse()?)?;
diff --git a/protocols/mdns/tests/use-tokio.rs b/protocols/mdns/tests/use-tokio.rs
index 830557d3f00..2ac96d9723c 100644
--- a/protocols/mdns/tests/use-tokio.rs
+++ b/protocols/mdns/tests/use-tokio.rs
@@ -19,10 +19,12 @@
 // DEALINGS IN THE SOFTWARE.use futures::StreamExt;
 use futures::StreamExt;
 use libp2p::{
+    core::{upgrade::Version, Transport},
     identity,
     mdns::{MdnsConfig, MdnsEvent, TokioMdns},
+    noise,
     swarm::{Swarm, SwarmEvent},
-    PeerId,
+    tcp, yamux, PeerId,
 };
 use std::error::Error;
 use std::time::Duration;
@@ -56,7 +58,11 @@ async fn test_expired_tokio() -> Result<(), Box<dyn Error>> {
 async fn create_swarm(config: MdnsConfig) -> Result<Swarm<TokioMdns>, Box<dyn Error>> {
     let id_keys = identity::Keypair::generate_ed25519();
     let peer_id = PeerId::from(id_keys.public());
-    let transport = libp2p::tokio_development_transport(id_keys)?;
+    let transport = tcp::TcpTransport::default()
+        .upgrade(Version::V1)
+        .authenticate(noise::NoiseAuthenticated::xx(&id_keys)?)
+        .multiplex(yamux::YamuxConfig::default())
+        .boxed();
     let behaviour = TokioMdns::new(config)?;
     let mut swarm = Swarm::new(transport, behaviour, peer_id);
     swarm.listen_on("/ip4/0.0.0.0/tcp/0".parse()?)?;
diff --git a/protocols/rendezvous/examples/discover.rs b/protocols/rendezvous/examples/discover.rs
index c14e114ee88..07ccbfa8f66 100644
--- a/protocols/rendezvous/examples/discover.rs
+++ b/protocols/rendezvous/examples/discover.rs
@@ -25,7 +25,10 @@ use libp2p::multiaddr::Protocol;
 use libp2p::ping;
 use libp2p::swarm::{keep_alive, SwarmEvent};
 use libp2p::Swarm;
-use libp2p::{development_transport, rendezvous, Multiaddr};
+use libp2p::{
+    core::{upgrade::Version, Transport},
+    noise, rendezvous, tcp, yamux, Multiaddr,
+};
 use std::time::Duration;
 use void::Void;
 
@@ -42,7 +45,11 @@ async fn main() {
         .unwrap();
 
     let mut swarm = Swarm::new(
-        development_transport(identity.clone()).await.unwrap(),
+        tcp::TcpTransport::default()
+            .upgrade(Version::V1)
+            .authenticate(noise::NoiseAuthenticated::xx(&identity).unwrap())
+            .multiplex(yamux::YamuxConfig::default())
+            .boxed(),
         MyBehaviour {
             rendezvous: rendezvous::client::Behaviour::new(identity.clone()),
             ping: ping::Behaviour::new(ping::Config::new().with_interval(Duration::from_secs(1))),
diff --git a/protocols/rendezvous/examples/register.rs b/protocols/rendezvous/examples/register.rs
index 3fbfa02785d..cb9fb0fe08a 100644
--- a/protocols/rendezvous/examples/register.rs
+++ b/protocols/rendezvous/examples/register.rs
@@ -23,7 +23,10 @@ use libp2p::core::identity;
 use libp2p::core::PeerId;
 use libp2p::ping;
 use libp2p::swarm::{Swarm, SwarmEvent};
-use libp2p::{development_transport, rendezvous};
+use libp2p::{
+    core::{upgrade::Version, Transport},
+    noise, rendezvous, tcp, yamux,
+};
 use libp2p::{Multiaddr, NetworkBehaviour};
 use libp2p_swarm::AddressScore;
 use std::time::Duration;
@@ -40,7 +43,11 @@ async fn main() {
     let identity = identity::Keypair::generate_ed25519();
 
     let mut swarm = Swarm::new(
-        development_transport(identity.clone()).await.unwrap(),
+        tcp::TcpTransport::default()
+            .upgrade(Version::V1)
+            .authenticate(noise::NoiseAuthenticated::xx(&identity).unwrap())
+            .multiplex(yamux::YamuxConfig::default())
+            .boxed(),
         MyBehaviour {
             rendezvous: rendezvous::client::Behaviour::new(identity.clone()),
             ping: ping::Behaviour::new(ping::Config::new().with_interval(Duration::from_secs(1))),
diff --git a/protocols/rendezvous/examples/register_with_identify.rs b/protocols/rendezvous/examples/register_with_identify.rs
index f12a1a6ed98..93092aee911 100644
--- a/protocols/rendezvous/examples/register_with_identify.rs
+++ b/protocols/rendezvous/examples/register_with_identify.rs
@@ -24,7 +24,7 @@ use libp2p::core::PeerId;
 use libp2p::identify;
 use libp2p::ping;
 use libp2p::swarm::{keep_alive, Swarm, SwarmEvent};
-use libp2p::{development_transport, rendezvous};
+use libp2p::{core::upgrade::Version, core::Transport, noise, rendezvous, tcp, yamux};
 use libp2p::{Multiaddr, NetworkBehaviour};
 use std::time::Duration;
 use void::Void;
@@ -41,7 +41,11 @@ async fn main() {
     let identity = identity::Keypair::generate_ed25519();
 
     let mut swarm = Swarm::new(
-        development_transport(identity.clone()).await.unwrap(),
+        tcp::TcpTransport::default()
+            .upgrade(Version::V1)
+            .authenticate(noise::NoiseAuthenticated::xx(&identity).unwrap())
+            .multiplex(yamux::YamuxConfig::default())
+            .boxed(),
         MyBehaviour {
             identify: identify::Behaviour::new(identify::Config::new(
                 "rendezvous-example/1.0.0".to_string(),
diff --git a/protocols/rendezvous/examples/rendezvous_point.rs b/protocols/rendezvous/examples/rendezvous_point.rs
index 980a3a6fd5d..16e35b2bf2a 100644
--- a/protocols/rendezvous/examples/rendezvous_point.rs
+++ b/protocols/rendezvous/examples/rendezvous_point.rs
@@ -25,7 +25,7 @@ use libp2p::identify;
 use libp2p::ping;
 use libp2p::swarm::{keep_alive, Swarm, SwarmEvent};
 use libp2p::NetworkBehaviour;
-use libp2p::{development_transport, rendezvous};
+use libp2p::{core::upgrade::Version, core::Transport, noise, rendezvous, tcp, yamux};
 use void::Void;
 
 /// Examples for the rendezvous protocol:
@@ -45,7 +45,11 @@ async fn main() {
     let identity = identity::Keypair::Ed25519(key.into());
 
     let mut swarm = Swarm::new(
-        development_transport(identity.clone()).await.unwrap(),
+        tcp::TcpTransport::default()
+            .upgrade(Version::V1)
+            .authenticate(noise::NoiseAuthenticated::xx(&identity).unwrap())
+            .multiplex(yamux::YamuxConfig::default())
+            .boxed(),
         MyBehaviour {
             identify: identify::Behaviour::new(identify::Config::new(
                 "rendezvous-example/1.0.0".to_string(),
diff --git a/src/lib.rs b/src/lib.rs
index d2b4226d2ce..e040df62ca5 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -212,6 +212,10 @@ pub use libp2p_swarm_derive::NetworkBehaviour;
         note = "The `tcp-async-io` and `dns-async-std` features are deprecated. Use the new `tcp` and `dns` features together with the `async-std` feature."
     )
 )]
+#[deprecated(
+    since = "0.50.0",
+    note = "Compose your own transport, specific to your needs."
+)]
 pub async fn development_transport(
     keypair: identity::Keypair,
 ) -> std::io::Result<core::transport::Boxed<(PeerId, core::muxing::StreamMuxerBox)>> {
@@ -286,6 +290,10 @@ pub async fn development_transport(
         note = "The `tcp-tokio` and `dns-tokio` features are deprecated. Use the new `tcp` and `dns` feature together with the `tokio` feature."
     )
 )]
+#[deprecated(
+    since = "0.50.0",
+    note = "Compose your own transport, specific to your needs."
+)]
 pub fn tokio_development_transport(
     keypair: identity::Keypair,
 ) -> std::io::Result<core::transport::Boxed<(PeerId, core::muxing::StreamMuxerBox)>> {

From fc2d8a6c0dbc05fba7c99b0591bf54932c202d02 Mon Sep 17 00:00:00 2001
From: Thomas Eizinger <thomas@eizinger.io>
Date: Mon, 24 Oct 2022 15:57:19 +1100
Subject: [PATCH 2/4] Fill in PR number in changelog

---
 CHANGELOG.md | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index dda643cda4b..82f126377ef 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -51,11 +51,11 @@
 - Introduce [`libp2p-tls` `v0.1.0`](transports/tls/CHANGELOG.md#010). See [PR 2945].
 - Update individual crates.
   - Update to [`libp2p-tcp` `v0.38.0`](transports/tcp/CHANGELOG.md#0380).
-- Deprecate `development_transport` and `tokio_development_transport`. See [PR XXXX].
+- Deprecate `development_transport` and `tokio_development_transport`. See [PR 3056].
 
 [PR 3001]: https://github.com/libp2p/rust-libp2p/pull/3001
 [PR 2945]: https://github.com/libp2p/rust-libp2p/pull/2945
-[PR XXXX]: https://github.com/libp2p/rust-libp2p/pull/XXXX
+[PR 3056]: https://github.com/libp2p/rust-libp2p/pull/3056
 
 # 0.49.0
 

From 8708688b7cf79a55b8a0bb2a24599086d67e5723 Mon Sep 17 00:00:00 2001
From: Thomas Eizinger <thomas@eizinger.io>
Date: Wed, 26 Oct 2022 11:40:49 +1100
Subject: [PATCH 3/4] Update examples to not depend on deprecated symbols

---
 examples/chat.rs                                    |  2 +-
 examples/distributed-key-value-store.rs             |  2 +-
 examples/file-sharing.rs                            |  2 +-
 examples/gossipsub-chat.rs                          |  2 +-
 examples/ipfs-kad.rs                                |  2 +-
 examples/mdns-passive-discovery.rs                  |  2 +-
 examples/ping.rs                                    |  2 +-
 misc/metrics/examples/metrics/main.rs               |  2 +-
 protocols/autonat/examples/autonat_client.rs        |  2 +-
 protocols/autonat/examples/autonat_server.rs        |  2 +-
 protocols/autonat/tests/test_client.rs              |  2 +-
 protocols/autonat/tests/test_server.rs              |  2 +-
 protocols/identify/examples/identify.rs             |  2 +-
 protocols/mdns/tests/use-async-std.rs               |  2 +-
 protocols/mdns/tests/use-tokio.rs                   |  9 +++++++--
 protocols/rendezvous/examples/discover.rs           | 13 ++++++++-----
 protocols/rendezvous/examples/register.rs           | 12 ++++++++----
 .../rendezvous/examples/register_with_identify.rs   | 12 ++++++++----
 protocols/rendezvous/examples/rendezvous_point.rs   | 12 ++++++++----
 19 files changed, 53 insertions(+), 33 deletions(-)

diff --git a/examples/chat.rs b/examples/chat.rs
index 11e1cb4ef78..86b85eb5b08 100644
--- a/examples/chat.rs
+++ b/examples/chat.rs
@@ -74,7 +74,7 @@ async fn main() -> Result<(), Box<dyn Error>> {
     let local_peer_id = PeerId::from(local_key.public());
     println!("Local peer id: {:?}", local_peer_id);
 
-    let transport = tcp::TcpTransport::default()
+    let transport = tcp::async_io::Transport::default()
         .upgrade(Version::V1)
         .authenticate(noise::NoiseAuthenticated::xx(&local_key)?)
         .multiplex(yamux::YamuxConfig::default())
diff --git a/examples/distributed-key-value-store.rs b/examples/distributed-key-value-store.rs
index 13ea33761a1..dbef5034658 100644
--- a/examples/distributed-key-value-store.rs
+++ b/examples/distributed-key-value-store.rs
@@ -65,7 +65,7 @@ async fn main() -> Result<(), Box<dyn Error>> {
     let local_key = identity::Keypair::generate_ed25519();
     let local_peer_id = PeerId::from(local_key.public());
 
-    let transport = tcp::TcpTransport::default()
+    let transport = tcp::async_io::Transport::default()
         .upgrade(Version::V1)
         .authenticate(noise::NoiseAuthenticated::xx(&local_key)?)
         .multiplex(yamux::YamuxConfig::default())
diff --git a/examples/file-sharing.rs b/examples/file-sharing.rs
index 76d28e5ee02..94c698e4826 100644
--- a/examples/file-sharing.rs
+++ b/examples/file-sharing.rs
@@ -255,7 +255,7 @@ mod network {
         // Build the Swarm, connecting the lower layer transport logic with the
         // higher layer network behaviour logic.
         let swarm = SwarmBuilder::new(
-            tcp::TcpTransport::default()
+            tcp::async_io::Transport::default()
                 .upgrade(Version::V1)
                 .authenticate(noise::NoiseAuthenticated::xx(&id_keys)?)
                 .multiplex(yamux::YamuxConfig::default())
diff --git a/examples/gossipsub-chat.rs b/examples/gossipsub-chat.rs
index b67c40da51b..6bd8aacd5dc 100644
--- a/examples/gossipsub-chat.rs
+++ b/examples/gossipsub-chat.rs
@@ -73,7 +73,7 @@ async fn main() -> Result<(), Box<dyn Error>> {
     let local_peer_id = PeerId::from(local_key.public());
     println!("Local peer id: {:?}", local_peer_id);
 
-    let transport = tcp::TcpTransport::default()
+    let transport = tcp::async_io::Transport::default()
         .upgrade(Version::V1)
         .authenticate(noise::NoiseAuthenticated::xx(&local_key).unwrap())
         .multiplex(yamux::YamuxConfig::default())
diff --git a/examples/ipfs-kad.rs b/examples/ipfs-kad.rs
index b09b633e98d..0471f4d46a4 100644
--- a/examples/ipfs-kad.rs
+++ b/examples/ipfs-kad.rs
@@ -51,7 +51,7 @@ async fn main() -> Result<(), Box<dyn Error>> {
     let local_key = identity::Keypair::generate_ed25519();
     let local_peer_id = PeerId::from(local_key.public());
 
-    let transport = tcp::TcpTransport::default()
+    let transport = tcp::async_io::Transport::default()
         .upgrade(Version::V1)
         .authenticate(noise::NoiseAuthenticated::xx(&local_key)?)
         .multiplex(yamux::YamuxConfig::default())
diff --git a/examples/mdns-passive-discovery.rs b/examples/mdns-passive-discovery.rs
index 9b66673e7f4..3195f918b02 100644
--- a/examples/mdns-passive-discovery.rs
+++ b/examples/mdns-passive-discovery.rs
@@ -39,7 +39,7 @@ async fn main() -> Result<(), Box<dyn Error>> {
     println!("Local peer id: {:?}", peer_id);
 
     // Create a transport.
-    let transport = tcp::TcpTransport::default()
+    let transport = tcp::async_io::Transport::default()
         .upgrade(Version::V1)
         .authenticate(noise::NoiseAuthenticated::xx(&id_keys)?)
         .multiplex(yamux::YamuxConfig::default())
diff --git a/examples/ping.rs b/examples/ping.rs
index c5504706cc4..779ef47329a 100644
--- a/examples/ping.rs
+++ b/examples/ping.rs
@@ -55,7 +55,7 @@ async fn main() -> Result<(), Box<dyn Error>> {
     let local_peer_id = PeerId::from(local_key.public());
     println!("Local peer id: {:?}", local_peer_id);
 
-    let transport = tcp::TcpTransport::default()
+    let transport = tcp::async_io::Transport::default()
         .upgrade(Version::V1)
         .authenticate(noise::NoiseAuthenticated::xx(&local_key)?)
         .multiplex(yamux::YamuxConfig::default())
diff --git a/misc/metrics/examples/metrics/main.rs b/misc/metrics/examples/metrics/main.rs
index c86d9eeea5d..48605af3b4c 100644
--- a/misc/metrics/examples/metrics/main.rs
+++ b/misc/metrics/examples/metrics/main.rs
@@ -74,7 +74,7 @@ fn main() -> Result<(), Box<dyn Error>> {
     info!("Local peer id: {:?}", local_peer_id);
 
     let mut swarm = Swarm::new(
-        tcp::TcpTransport::default()
+        tcp::async_io::Transport::default()
             .upgrade(Version::V1)
             .authenticate(noise::NoiseAuthenticated::xx(&local_key)?)
             .multiplex(yamux::YamuxConfig::default())
diff --git a/protocols/autonat/examples/autonat_client.rs b/protocols/autonat/examples/autonat_client.rs
index de0e7a4cb9b..7c2460a0d6a 100644
--- a/protocols/autonat/examples/autonat_client.rs
+++ b/protocols/autonat/examples/autonat_client.rs
@@ -68,7 +68,7 @@ async fn main() -> Result<(), Box<dyn Error>> {
     let local_peer_id = PeerId::from(local_key.public());
     println!("Local peer id: {:?}", local_peer_id);
 
-    let transport = tcp::TcpTransport::default()
+    let transport = tcp::async_io::Transport::default()
         .upgrade(Version::V1)
         .authenticate(noise::NoiseAuthenticated::xx(&local_key)?)
         .multiplex(yamux::YamuxConfig::default())
diff --git a/protocols/autonat/examples/autonat_server.rs b/protocols/autonat/examples/autonat_server.rs
index 88b33d0ca20..5b9c09090ae 100644
--- a/protocols/autonat/examples/autonat_server.rs
+++ b/protocols/autonat/examples/autonat_server.rs
@@ -58,7 +58,7 @@ async fn main() -> Result<(), Box<dyn Error>> {
     let local_peer_id = PeerId::from(local_key.public());
     println!("Local peer id: {:?}", local_peer_id);
 
-    let transport = tcp::TcpTransport::default()
+    let transport = tcp::async_io::Transport::default()
         .upgrade(Version::V1)
         .authenticate(noise::NoiseAuthenticated::xx(&local_key)?)
         .multiplex(yamux::YamuxConfig::default())
diff --git a/protocols/autonat/tests/test_client.rs b/protocols/autonat/tests/test_client.rs
index 70af148301a..2298c16a882 100644
--- a/protocols/autonat/tests/test_client.rs
+++ b/protocols/autonat/tests/test_client.rs
@@ -40,7 +40,7 @@ const TEST_REFRESH_INTERVAL: Duration = Duration::from_secs(2);
 async fn init_swarm(config: Config) -> Swarm<Behaviour> {
     let keypair = Keypair::generate_ed25519();
     let local_id = PeerId::from_public_key(&keypair.public());
-    let transport = tcp::TcpTransport::default()
+    let transport = tcp::async_io::Transport::default()
         .upgrade(Version::V1)
         .authenticate(noise::NoiseAuthenticated::xx(&keypair).unwrap())
         .multiplex(yamux::YamuxConfig::default())
diff --git a/protocols/autonat/tests/test_server.rs b/protocols/autonat/tests/test_server.rs
index c59f4c111e6..b7dbe4e40cd 100644
--- a/protocols/autonat/tests/test_server.rs
+++ b/protocols/autonat/tests/test_server.rs
@@ -39,7 +39,7 @@ use std::{num::NonZeroU32, time::Duration};
 async fn init_swarm(config: Config) -> Swarm<Behaviour> {
     let keypair = Keypair::generate_ed25519();
     let local_id = PeerId::from_public_key(&keypair.public());
-    let transport = tcp::TcpTransport::default()
+    let transport = tcp::async_io::Transport::default()
         .upgrade(Version::V1)
         .authenticate(noise::NoiseAuthenticated::xx(&keypair).unwrap())
         .multiplex(yamux::YamuxConfig::default())
diff --git a/protocols/identify/examples/identify.rs b/protocols/identify/examples/identify.rs
index 2196c4b0f7e..a421283dab9 100644
--- a/protocols/identify/examples/identify.rs
+++ b/protocols/identify/examples/identify.rs
@@ -50,7 +50,7 @@ async fn main() -> Result<(), Box<dyn Error>> {
     let local_peer_id = PeerId::from(local_key.public());
     println!("Local peer id: {:?}", local_peer_id);
 
-    let transport = tcp::TcpTransport::default()
+    let transport = tcp::async_io::Transport::default()
         .upgrade(Version::V1)
         .authenticate(noise::NoiseAuthenticated::xx(&local_key)?)
         .multiplex(yamux::YamuxConfig::default())
diff --git a/protocols/mdns/tests/use-async-std.rs b/protocols/mdns/tests/use-async-std.rs
index 1a98bddc27c..0c4d0b7a1bc 100644
--- a/protocols/mdns/tests/use-async-std.rs
+++ b/protocols/mdns/tests/use-async-std.rs
@@ -62,7 +62,7 @@ async fn test_expired_async_std() -> Result<(), Box<dyn Error>> {
 async fn create_swarm(config: MdnsConfig) -> Result<Swarm<Mdns>, Box<dyn Error>> {
     let id_keys = identity::Keypair::generate_ed25519();
     let peer_id = PeerId::from(id_keys.public());
-    let transport = tcp::TcpTransport::default()
+    let transport = tcp::async_io::Transport::default()
         .upgrade(Version::V1)
         .authenticate(noise::NoiseAuthenticated::xx(&id_keys)?)
         .multiplex(yamux::YamuxConfig::default())
diff --git a/protocols/mdns/tests/use-tokio.rs b/protocols/mdns/tests/use-tokio.rs
index 2ac96d9723c..eedc0532706 100644
--- a/protocols/mdns/tests/use-tokio.rs
+++ b/protocols/mdns/tests/use-tokio.rs
@@ -26,6 +26,7 @@ use libp2p::{
     swarm::{Swarm, SwarmEvent},
     tcp, yamux, PeerId,
 };
+use libp2p_swarm::SwarmBuilder;
 use std::error::Error;
 use std::time::Duration;
 
@@ -58,13 +59,17 @@ async fn test_expired_tokio() -> Result<(), Box<dyn Error>> {
 async fn create_swarm(config: MdnsConfig) -> Result<Swarm<TokioMdns>, Box<dyn Error>> {
     let id_keys = identity::Keypair::generate_ed25519();
     let peer_id = PeerId::from(id_keys.public());
-    let transport = tcp::TcpTransport::default()
+    let transport = tcp::tokio::Transport::default()
         .upgrade(Version::V1)
         .authenticate(noise::NoiseAuthenticated::xx(&id_keys)?)
         .multiplex(yamux::YamuxConfig::default())
         .boxed();
     let behaviour = TokioMdns::new(config)?;
-    let mut swarm = Swarm::new(transport, behaviour, peer_id);
+    let mut swarm = SwarmBuilder::new(transport, behaviour, peer_id)
+        .executor(Box::new(|f| {
+            tokio::spawn(f);
+        }))
+        .build();
     swarm.listen_on("/ip4/0.0.0.0/tcp/0".parse()?)?;
     Ok(swarm)
 }
diff --git a/protocols/rendezvous/examples/discover.rs b/protocols/rendezvous/examples/discover.rs
index 07ccbfa8f66..643225130db 100644
--- a/protocols/rendezvous/examples/discover.rs
+++ b/protocols/rendezvous/examples/discover.rs
@@ -23,8 +23,7 @@ use libp2p::core::identity;
 use libp2p::core::PeerId;
 use libp2p::multiaddr::Protocol;
 use libp2p::ping;
-use libp2p::swarm::{keep_alive, SwarmEvent};
-use libp2p::Swarm;
+use libp2p::swarm::{keep_alive, SwarmBuilder, SwarmEvent};
 use libp2p::{
     core::{upgrade::Version, Transport},
     noise, rendezvous, tcp, yamux, Multiaddr,
@@ -44,8 +43,8 @@ async fn main() {
         .parse()
         .unwrap();
 
-    let mut swarm = Swarm::new(
-        tcp::TcpTransport::default()
+    let mut swarm = SwarmBuilder::new(
+        tcp::tokio::Transport::default()
             .upgrade(Version::V1)
             .authenticate(noise::NoiseAuthenticated::xx(&identity).unwrap())
             .multiplex(yamux::YamuxConfig::default())
@@ -56,7 +55,11 @@ async fn main() {
             keep_alive: keep_alive::Behaviour,
         },
         PeerId::from(identity.public()),
-    );
+    )
+    .executor(Box::new(|f| {
+        tokio::spawn(f);
+    }))
+    .build();
 
     log::info!("Local peer id: {}", swarm.local_peer_id());
 
diff --git a/protocols/rendezvous/examples/register.rs b/protocols/rendezvous/examples/register.rs
index cb9fb0fe08a..dc6bca95ede 100644
--- a/protocols/rendezvous/examples/register.rs
+++ b/protocols/rendezvous/examples/register.rs
@@ -22,7 +22,7 @@ use futures::StreamExt;
 use libp2p::core::identity;
 use libp2p::core::PeerId;
 use libp2p::ping;
-use libp2p::swarm::{Swarm, SwarmEvent};
+use libp2p::swarm::{SwarmBuilder, SwarmEvent};
 use libp2p::{
     core::{upgrade::Version, Transport},
     noise, rendezvous, tcp, yamux,
@@ -42,8 +42,8 @@ async fn main() {
 
     let identity = identity::Keypair::generate_ed25519();
 
-    let mut swarm = Swarm::new(
-        tcp::TcpTransport::default()
+    let mut swarm = SwarmBuilder::new(
+        tcp::tokio::Transport::default()
             .upgrade(Version::V1)
             .authenticate(noise::NoiseAuthenticated::xx(&identity).unwrap())
             .multiplex(yamux::YamuxConfig::default())
@@ -53,7 +53,11 @@ async fn main() {
             ping: ping::Behaviour::new(ping::Config::new().with_interval(Duration::from_secs(1))),
         },
         PeerId::from(identity.public()),
-    );
+    )
+    .executor(Box::new(|f| {
+        tokio::spawn(f);
+    }))
+    .build();
 
     // In production the external address should be the publicly facing IP address of the rendezvous point.
     // This address is recorded in the registration entry by the rendezvous point.
diff --git a/protocols/rendezvous/examples/register_with_identify.rs b/protocols/rendezvous/examples/register_with_identify.rs
index 93092aee911..7c71056f084 100644
--- a/protocols/rendezvous/examples/register_with_identify.rs
+++ b/protocols/rendezvous/examples/register_with_identify.rs
@@ -23,7 +23,7 @@ use libp2p::core::identity;
 use libp2p::core::PeerId;
 use libp2p::identify;
 use libp2p::ping;
-use libp2p::swarm::{keep_alive, Swarm, SwarmEvent};
+use libp2p::swarm::{keep_alive, SwarmBuilder, SwarmEvent};
 use libp2p::{core::upgrade::Version, core::Transport, noise, rendezvous, tcp, yamux};
 use libp2p::{Multiaddr, NetworkBehaviour};
 use std::time::Duration;
@@ -40,8 +40,8 @@ async fn main() {
 
     let identity = identity::Keypair::generate_ed25519();
 
-    let mut swarm = Swarm::new(
-        tcp::TcpTransport::default()
+    let mut swarm = SwarmBuilder::new(
+        tcp::tokio::Transport::default()
             .upgrade(Version::V1)
             .authenticate(noise::NoiseAuthenticated::xx(&identity).unwrap())
             .multiplex(yamux::YamuxConfig::default())
@@ -56,7 +56,11 @@ async fn main() {
             keep_alive: keep_alive::Behaviour,
         },
         PeerId::from(identity.public()),
-    );
+    )
+    .executor(Box::new(|f| {
+        tokio::spawn(f);
+    }))
+    .build();
 
     log::info!("Local peer id: {}", swarm.local_peer_id());
 
diff --git a/protocols/rendezvous/examples/rendezvous_point.rs b/protocols/rendezvous/examples/rendezvous_point.rs
index 16e35b2bf2a..9c66e8c9535 100644
--- a/protocols/rendezvous/examples/rendezvous_point.rs
+++ b/protocols/rendezvous/examples/rendezvous_point.rs
@@ -23,7 +23,7 @@ use libp2p::core::identity;
 use libp2p::core::PeerId;
 use libp2p::identify;
 use libp2p::ping;
-use libp2p::swarm::{keep_alive, Swarm, SwarmEvent};
+use libp2p::swarm::{keep_alive, SwarmBuilder, SwarmEvent};
 use libp2p::NetworkBehaviour;
 use libp2p::{core::upgrade::Version, core::Transport, noise, rendezvous, tcp, yamux};
 use void::Void;
@@ -44,8 +44,8 @@ async fn main() {
     let key = identity::ed25519::SecretKey::from_bytes(bytes).expect("we always pass 32 bytes");
     let identity = identity::Keypair::Ed25519(key.into());
 
-    let mut swarm = Swarm::new(
-        tcp::TcpTransport::default()
+    let mut swarm = SwarmBuilder::new(
+        tcp::tokio::Transport::default()
             .upgrade(Version::V1)
             .authenticate(noise::NoiseAuthenticated::xx(&identity).unwrap())
             .multiplex(yamux::YamuxConfig::default())
@@ -60,7 +60,11 @@ async fn main() {
             keep_alive: keep_alive::Behaviour,
         },
         PeerId::from(identity.public()),
-    );
+    )
+    .executor(Box::new(|f| {
+        tokio::spawn(f);
+    }))
+    .build();
 
     log::info!("Local peer id: {}", swarm.local_peer_id());
 

From 1d838a158debfe87e20fd314f0354bf7b53efbed Mon Sep 17 00:00:00 2001
From: Thomas Eizinger <thomas@eizinger.io>
Date: Sun, 13 Nov 2022 13:09:48 +1100
Subject: [PATCH 4/4] Remove deprecation

---
 CHANGELOG.md | 2 --
 src/lib.rs   | 8 --------
 2 files changed, 10 deletions(-)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 1d8b0d8a0e0..e4393d2bd3c 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -53,7 +53,6 @@
 - Remove `NetworkBehaviour` macro export from root crate in favor of re-exported macro from `libp2p::swarm`.
   Change your import from `libp2p::NetworkBehaviour` to `libp2p::swarm::NetworkBehaviour`. See [PR 3055].
 - Feature-gate `NetworkBehaviour` macro behind `macros` feature flag. See [PR 3055].
-- Deprecate `development_transport` and `tokio_development_transport`. See [PR 3056].
 - Update individual crates.
   - Update to [`libp2p-autonat` `v0.89.0`](protocols/autonat/CHANGELOG.md#090).
   - Update to [`libp2p-core` `v0.38.0`](core/CHANGELOG.md#0380).
@@ -84,7 +83,6 @@
 [PR 3001]: https://github.com/libp2p/rust-libp2p/pull/3001
 [PR 2945]: https://github.com/libp2p/rust-libp2p/pull/2945
 [PR 3055]: https://github.com/libp2p/rust-libp2p/pull/3055
-[PR 3056]: https://github.com/libp2p/rust-libp2p/pull/3056
 
 # 0.49.0
 
diff --git a/src/lib.rs b/src/lib.rs
index 7bde8d88561..e2468547065 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -178,10 +178,6 @@ pub use self::transport_ext::TransportExt;
         note = "The `tcp-async-io` and `dns-async-std` features are deprecated. Use the new `tcp` and `dns` features together with the `async-std` feature."
     )
 )]
-#[deprecated(
-    since = "0.50.0",
-    note = "Compose your own transport, specific to your needs."
-)]
 pub async fn development_transport(
     keypair: identity::Keypair,
 ) -> std::io::Result<core::transport::Boxed<(PeerId, core::muxing::StreamMuxerBox)>> {
@@ -242,10 +238,6 @@ pub async fn development_transport(
         note = "The `tcp-tokio` and `dns-tokio` features are deprecated. Use the new `tcp` and `dns` feature together with the `tokio` feature."
     )
 )]
-#[deprecated(
-    since = "0.50.0",
-    note = "Compose your own transport, specific to your needs."
-)]
 pub fn tokio_development_transport(
     keypair: identity::Keypair,
 ) -> std::io::Result<core::transport::Boxed<(PeerId, core::muxing::StreamMuxerBox)>> {