diff --git a/examples/custom.rs b/examples/custom.rs
index 2f0e73d14..83f6af9c0 100644
--- a/examples/custom.rs
+++ b/examples/custom.rs
@@ -48,6 +48,10 @@ impl HostTrait for MyHost {
         true
     }
 
+    fn new() -> Result<Self, Error> {
+        Ok(Self)
+    }
+
     fn devices(&self) -> Result<Self::Devices, Error> {
         Ok(std::iter::once(MyDevice))
     }
diff --git a/src/host/aaudio/mod.rs b/src/host/aaudio/mod.rs
index 2de6551bb..a54f57a48 100644
--- a/src/host/aaudio/mod.rs
+++ b/src/host/aaudio/mod.rs
@@ -158,16 +158,14 @@ struct BufferTuningState {
 pub use crate::iter::{SupportedInputConfigs, SupportedOutputConfigs};
 pub type Devices = std::vec::IntoIter<Device>;
 
-impl Host {
-    pub fn new() -> Result<Self, Error> {
-        Ok(Host)
-    }
-}
-
 impl HostTrait for Host {
     type Devices = Devices;
     type Device = Device;
 
+    fn new() -> Result<Self, Error> {
+        Ok(Host)
+    }
+
     fn is_available() -> bool {
         true
     }
diff --git a/src/host/alsa/mod.rs b/src/host/alsa/mod.rs
index 8898e3b4a..d22c8dbc4 100644
--- a/src/host/alsa/mod.rs
+++ b/src/host/alsa/mod.rs
@@ -37,18 +37,6 @@ pub struct Host {
 }
 
 impl Host {
-    pub fn new() -> Result<Self, Error> {
-        let inner = AlsaContext::new().map_err(|e| {
-            Error::with_message(
-                ErrorKind::HostUnavailable,
-                format!("ALSA is not available: {e}"),
-            )
-        })?;
-        Ok(Self {
-            inner: Arc::new(inner),
-        })
-    }
-
     // "default" is a virtual ALSA device that redirects to the configured default. We cannot
     // determine its actual capabilities without opening it, so we return Unknown direction.
     fn default_device(&self) -> Device {
@@ -65,6 +53,18 @@ impl HostTrait for Host {
     type Devices = Devices;
     type Device = Device;
 
+    fn new() -> Result<Self, Error> {
+        let inner = AlsaContext::new().map_err(|e| {
+            Error::with_message(
+                ErrorKind::HostUnavailable,
+                format!("ALSA is not available: {e}"),
+            )
+        })?;
+        Ok(Self {
+            inner: Arc::new(inner),
+        })
+    }
+
     fn is_available() -> bool {
         // Assume ALSA is always available on Linux and BSD.
         true
diff --git a/src/host/asio/mod.rs b/src/host/asio/mod.rs
index 3d91a1818..882b800ff 100644
--- a/src/host/asio/mod.rs
+++ b/src/host/asio/mod.rs
@@ -36,8 +36,11 @@ pub struct Host {
     asio: Arc<sys::Asio>,
 }
 
-impl Host {
-    pub fn new() -> Result<Self, Error> {
+impl HostTrait for Host {
+    type Devices = Devices;
+    type Device = Device;
+
+    fn new() -> Result<Self, Error> {
         com::com_initialized();
         let asio = GLOBAL_ASIO
             .get_or_init(|| Arc::new(sys::Asio::new()))
@@ -45,11 +48,6 @@ impl Host {
         let host = Host { asio };
         Ok(host)
     }
-}
-
-impl HostTrait for Host {
-    type Devices = Devices;
-    type Device = Device;
 
     fn is_available() -> bool {
         true
diff --git a/src/host/audioworklet/mod.rs b/src/host/audioworklet/mod.rs
index b25503580..383a2ae82 100644
--- a/src/host/audioworklet/mod.rs
+++ b/src/host/audioworklet/mod.rs
@@ -203,8 +203,11 @@ enum Command {
     Pause,
 }
 
-impl Host {
-    pub fn new() -> Result<Self, Error> {
+impl HostTrait for Host {
+    type Devices = Devices;
+    type Device = Device;
+
+    fn new() -> Result<Self, Error> {
         if Self::is_available() {
             Ok(Host)
         } else {
@@ -214,11 +217,6 @@ impl Host {
             ))
         }
     }
-}
-
-impl HostTrait for Host {
-    type Devices = Devices;
-    type Device = Device;
 
     fn is_available() -> bool {
         if let Some(window) = web_sys::window() {
diff --git a/src/host/coreaudio/ios/mod.rs b/src/host/coreaudio/ios/mod.rs
index 9a1eaf898..d664b095f 100644
--- a/src/host/coreaudio/ios/mod.rs
+++ b/src/host/coreaudio/ios/mod.rs
@@ -54,16 +54,14 @@ impl fmt::Display for Device {
 
 pub struct Host;
 
-impl Host {
-    pub fn new() -> Result<Self, Error> {
-        Ok(Host)
-    }
-}
-
 impl HostTrait for Host {
     type Devices = Devices;
     type Device = Device;
 
+    fn new() -> Result<Self, Error> {
+        Ok(Host)
+    }
+
     fn is_available() -> bool {
         true
     }
diff --git a/src/host/coreaudio/macos/mod.rs b/src/host/coreaudio/macos/mod.rs
index 7b53a40a5..60bbf88c0 100644
--- a/src/host/coreaudio/macos/mod.rs
+++ b/src/host/coreaudio/macos/mod.rs
@@ -34,16 +34,14 @@ pub use device::Device;
 #[derive(Debug)]
 pub struct Host;
 
-impl Host {
-    pub fn new() -> Result<Self, Error> {
-        Ok(Host)
-    }
-}
-
 impl HostTrait for Host {
     type Devices = Devices;
     type Device = Device;
 
+    fn new() -> Result<Self, Error> {
+        Ok(Host)
+    }
+
     fn is_available() -> bool {
         // Assume coreaudio is always available
         true
diff --git a/src/host/custom/mod.rs b/src/host/custom/mod.rs
index 2de8b5ff8..0a527f7ea 100644
--- a/src/host/custom/mod.rs
+++ b/src/host/custom/mod.rs
@@ -28,11 +28,6 @@ use crate::{
 pub struct Host(Box<dyn HostErased>);
 
 impl Host {
-    // this only exists for impl_platform_host, which requires it
-    pub(crate) fn new() -> Result<Self, Error> {
-        Err(Error::new(ErrorKind::HostUnavailable))
-    }
-
     /// Construct a custom host from an arbitrary [`HostTrait`] implementation.
     pub fn from_host<T>(host: T) -> Self
     where
@@ -356,6 +351,10 @@ impl HostTrait for Host {
     type Devices = Devices;
     type Device = Device;
 
+    fn new() -> Result<Self, Error> {
+        Err(Error::new(ErrorKind::HostUnavailable))
+    }
+
     fn is_available() -> bool {
         false
     }
diff --git a/src/host/jack/mod.rs b/src/host/jack/mod.rs
index 1315aeda2..ca87b199a 100644
--- a/src/host/jack/mod.rs
+++ b/src/host/jack/mod.rs
@@ -44,17 +44,6 @@ pub struct Host {
 }
 
 impl Host {
-    pub fn new() -> Result<Self, Error> {
-        let mut host = Host {
-            name: format!("cpal_client_{}", std::process::id()),
-            connect_ports_automatically: true,
-            start_server_automatically: false,
-            devices_created: vec![],
-        };
-        // Devices don't exist for JACK, they have to be created
-        host.initialize_default_devices();
-        Ok(host)
-    }
     /// Configures whether created ports should automatically connect to system playback/capture
     /// ports.
     ///
@@ -129,6 +118,18 @@ impl HostTrait for Host {
     type Devices = Devices;
     type Device = Device;
 
+    fn new() -> Result<Self, Error> {
+        let mut host = Host {
+            name: format!("cpal_client_{}", std::process::id()),
+            connect_ports_automatically: true,
+            start_server_automatically: false,
+            devices_created: vec![],
+        };
+        // Devices don't exist for JACK, they have to be created
+        host.initialize_default_devices();
+        Ok(host)
+    }
+
     /// JACK is available if
     /// - the jack feature flag is set
     /// - libjack is installed (wouldn't compile without it)
diff --git a/src/host/mod.rs b/src/host/mod.rs
index 34a92488d..76ec64c45 100644
--- a/src/host/mod.rs
+++ b/src/host/mod.rs
@@ -86,20 +86,23 @@ pub(crate) mod webaudio;
 #[cfg(feature = "custom")]
 pub(crate) mod custom;
 
-#[cfg(not(any(
-    windows,
-    target_os = "linux",
-    target_os = "dragonfly",
-    target_os = "freebsd",
-    target_os = "netbsd",
-    target_vendor = "apple",
-    target_os = "android",
-    all(
-        target_arch = "wasm32",
-        any(target_os = "emscripten", target_os = "unknown"),
-        feature = "wasm-bindgen"
-    ),
-)))]
+#[cfg(all(
+    not(feature = "custom"),
+    not(any(
+        windows,
+        target_os = "linux",
+        target_os = "dragonfly",
+        target_os = "freebsd",
+        target_os = "netbsd",
+        target_vendor = "apple",
+        target_os = "android",
+        all(
+            target_arch = "wasm32",
+            any(target_os = "emscripten", target_os = "unknown"),
+            feature = "wasm-bindgen"
+        ),
+    )),
+))]
 pub(crate) mod null;
 
 #[cfg(any(
diff --git a/src/host/null/mod.rs b/src/host/null/mod.rs
index 2cce813f3..d1e86b199 100644
--- a/src/host/null/mod.rs
+++ b/src/host/null/mod.rs
@@ -6,8 +6,10 @@ use std::fmt;
 use std::time::Duration;
 
 use crate::{
-    CallbackInfo, Data, DeviceDescription, DeviceDescriptionBuilder, DeviceId, Error, FrameCount,
-    SampleFormat, StreamConfig, StreamInstant, SupportedStreamConfig, SupportedStreamConfigRange,
+    CallbackInfo, Data, DeviceDescription, DeviceDescriptionBuilder, DeviceId, Error,
+    ErrorKind::DeviceNotAvailable,
+    FrameCount, SampleFormat, StreamConfig, StreamInstant, SupportedStreamConfig,
+    SupportedStreamConfigRange,
     traits::{DeviceTrait, HostTrait, StreamTrait},
 };
 
@@ -33,13 +35,6 @@ pub struct SupportedInputConfigs;
 #[derive(Clone)]
 pub struct SupportedOutputConfigs;
 
-impl Host {
-    #[allow(dead_code)]
-    pub fn new() -> Result<Self, Error> {
-        Ok(Self)
-    }
-}
-
 impl DeviceTrait for Device {
     type SupportedInputConfigs = SupportedInputConfigs;
     type SupportedOutputConfigs = SupportedOutputConfigs;
@@ -54,19 +49,19 @@ impl DeviceTrait for Device {
     }
 
     fn supported_input_configs(&self) -> Result<SupportedInputConfigs, Error> {
-        unimplemented!()
+        Err(Error::with_message(DeviceNotAvailable, "Null host in use"))
     }
 
     fn supported_output_configs(&self) -> Result<SupportedOutputConfigs, Error> {
-        unimplemented!()
+        Err(Error::with_message(DeviceNotAvailable, "Null host in use"))
     }
 
     fn default_input_config(&self) -> Result<SupportedStreamConfig, Error> {
-        unimplemented!()
+        Err(Error::with_message(DeviceNotAvailable, "Null host in use"))
     }
 
     fn default_output_config(&self) -> Result<SupportedStreamConfig, Error> {
-        unimplemented!()
+        Err(Error::with_message(DeviceNotAvailable, "Null host in use"))
     }
 
     fn build_input_stream_raw<D, E>(
@@ -81,7 +76,7 @@ impl DeviceTrait for Device {
         D: FnMut(&Data, &CallbackInfo) + Send + 'static,
         E: FnMut(Error) + Send + 'static,
     {
-        unimplemented!()
+        Err(Error::with_message(DeviceNotAvailable, "Null host in use"))
     }
 
     /// Create an output stream.
@@ -97,7 +92,7 @@ impl DeviceTrait for Device {
         D: FnMut(&mut Data, &CallbackInfo) + Send + 'static,
         E: FnMut(Error) + Send + 'static,
     {
-        unimplemented!()
+        Err(Error::with_message(DeviceNotAvailable, "Null host in use"))
     }
 }
 
@@ -105,6 +100,10 @@ impl HostTrait for Host {
     type Devices = Devices;
     type Device = Device;
 
+    fn new() -> Result<Self, Error> {
+        Ok(Self)
+    }
+
     fn is_available() -> bool {
         false
     }
@@ -124,23 +123,23 @@ impl HostTrait for Host {
 
 impl StreamTrait for Stream {
     fn start(&self) -> Result<(), Error> {
-        unimplemented!()
+        Err(Error::with_message(DeviceNotAvailable, "Null host in use"))
     }
 
     fn pause(&self) -> Result<(), Error> {
-        unimplemented!()
+        Err(Error::with_message(DeviceNotAvailable, "Null host in use"))
     }
 
     fn stop(&self, _timeout: Option<std::time::Duration>) -> Result<(), Error> {
-        unimplemented!()
+        Err(Error::with_message(DeviceNotAvailable, "Null host in use"))
     }
 
     fn now(&self) -> StreamInstant {
-        unimplemented!()
+        StreamInstant::ZERO
     }
 
     fn buffer_size(&self) -> Result<FrameCount, Error> {
-        unimplemented!()
+        Err(Error::with_message(DeviceNotAvailable, "Null host in use"))
     }
 }
 
diff --git a/src/host/pipewire/mod.rs b/src/host/pipewire/mod.rs
index 412dd3d5c..fb7511d99 100644
--- a/src/host/pipewire/mod.rs
+++ b/src/host/pipewire/mod.rs
@@ -29,19 +29,6 @@ pub struct Host {
 }
 
 impl Host {
-    pub fn new() -> Result<Self, Error> {
-        let _pw = PwInitGuard::new();
-        let connect_automatically = Arc::new(AtomicBool::new(true));
-        let devices = init_devices(connect_automatically.clone()).ok_or_else(|| {
-            Error::with_message(ErrorKind::HostUnavailable, "PipeWire is not available")
-        })?;
-        Ok(Self {
-            _pw,
-            devices,
-            connect_automatically,
-        })
-    }
-
     /// Configures whether created streams should automatically connect to system playback/capture
     /// nodes via the session manager.
     ///
@@ -60,6 +47,19 @@ impl HostTrait for Host {
     type Devices = Devices;
     type Device = Device;
 
+    fn new() -> Result<Self, Error> {
+        let _pw = PwInitGuard::new();
+        let connect_automatically = Arc::new(AtomicBool::new(true));
+        let devices = init_devices(connect_automatically.clone()).ok_or_else(|| {
+            Error::with_message(ErrorKind::HostUnavailable, "PipeWire is not available")
+        })?;
+        Ok(Self {
+            _pw,
+            devices,
+            connect_automatically,
+        })
+    }
+
     fn is_available() -> bool {
         utils::find_socket_path().is_some()
     }
diff --git a/src/host/pulseaudio/mod.rs b/src/host/pulseaudio/mod.rs
index 6a0280b78..d02712d7b 100644
--- a/src/host/pulseaudio/mod.rs
+++ b/src/host/pulseaudio/mod.rs
@@ -128,8 +128,11 @@ pub struct Host {
     client: pulseaudio::Client,
 }
 
-impl Host {
-    pub fn new() -> Result<Self, Error> {
+impl HostTrait for Host {
+    type Devices = std::vec::IntoIter<Device>;
+    type Device = Device;
+
+    fn new() -> Result<Self, Error> {
         // `Client::from_env` does a blocking auth handshake with no socket timeout. If this never
         // returns, fall through to the next host with no other option than to leak the thread.
         let (tx, rx) = mpsc::channel();
@@ -153,11 +156,6 @@ impl Host {
 
         Ok(Self { client })
     }
-}
-
-impl HostTrait for Host {
-    type Devices = std::vec::IntoIter<Device>;
-    type Device = Device;
 
     fn is_available() -> bool {
         pulseaudio::socket_path_from_env().is_some()
diff --git a/src/host/wasapi/mod.rs b/src/host/wasapi/mod.rs
index 999d1ab86..487e936d0 100644
--- a/src/host/wasapi/mod.rs
+++ b/src/host/wasapi/mod.rs
@@ -32,16 +32,14 @@ mod stream;
 #[derive(Debug)]
 pub struct Host;
 
-impl Host {
-    pub fn new() -> Result<Self, Error> {
-        Ok(Host)
-    }
-}
-
 impl HostTrait for Host {
     type Devices = Devices;
     type Device = Device;
 
+    fn new() -> Result<Self, Error> {
+        Ok(Host)
+    }
+
     fn is_available() -> bool {
         // Assume WASAPI is always available on Windows.
         true
diff --git a/src/host/webaudio/mod.rs b/src/host/webaudio/mod.rs
index 422fa26de..e3d20e91f 100644
--- a/src/host/webaudio/mod.rs
+++ b/src/host/webaudio/mod.rs
@@ -159,8 +159,11 @@ const SCRIPT_PROCESSOR_VALID_BUFFER_SIZES: [usize; 7] = [256, 512, 1024, 2048, 4
 const SCRIPT_PROCESSOR_MIN_BUFFER_SIZE: usize = 256;
 const SCRIPT_PROCESSOR_MAX_BUFFER_SIZE: usize = 16384;
 
-impl Host {
-    pub fn new() -> Result<Self, Error> {
+impl HostTrait for Host {
+    type Devices = Devices;
+    type Device = Device;
+
+    fn new() -> Result<Self, Error> {
         if Self::is_available() {
             Ok(Self)
         } else {
@@ -170,11 +173,6 @@ impl Host {
             ))
         }
     }
-}
-
-impl HostTrait for Host {
-    type Devices = Devices;
-    type Device = Device;
 
     fn is_available() -> bool {
         is_webaudio_available()
diff --git a/src/platform/mod.rs b/src/platform/mod.rs
index 96da987a3..e5e55ece2 100644
--- a/src/platform/mod.rs
+++ b/src/platform/mod.rs
@@ -581,6 +581,19 @@ macro_rules! impl_platform_host {
                 false
             }
 
+            fn new() -> Result<Self, crate::Error>
+            where
+                Self: Sized,
+            {
+                $(
+                    $(#[cfg($feat)])?
+                    if let Ok(host) = <$Host>::new() {
+                        return Ok(host.into());
+                    }
+                )*
+                Err(crate::Error::new(crate::ErrorKind::HostUnavailable))
+            }
+
             fn devices(&self) -> Result<Self::Devices, crate::Error> {
                 match self.0 {
                     $(
@@ -835,7 +848,7 @@ macro_rules! impl_platform_host {
                 $(
                     $(#[cfg($feat)])?
                     HostId::$HostVariant => {
-                        <$Host>::new()
+                        <$Host as crate::traits::HostTrait>::new()
                             .map(HostInner::$HostVariant)
                             .map(Host::from)
                     }
@@ -886,17 +899,17 @@ mod platform_impl {
     pub fn default_host() -> Host {
         #[cfg(feature = "pipewire")]
         if <PipeWireHost as crate::traits::HostTrait>::is_available() {
-            if let Ok(host) = PipeWireHost::new() {
+            if let Ok(host) = <PipeWireHost as crate::traits::HostTrait>::new() {
                 return host.into();
             }
         }
         #[cfg(feature = "pulseaudio")]
         if <PulseAudioHost as crate::traits::HostTrait>::is_available() {
-            if let Ok(host) = PulseAudioHost::new() {
+            if let Ok(host) = <PulseAudioHost as crate::traits::HostTrait>::new() {
                 return host.into();
             }
         }
-        AlsaHost::new()
+        <AlsaHost as crate::traits::HostTrait>::new()
             .expect("the default host should always be available")
             .into()
     }
@@ -916,7 +929,7 @@ mod platform_impl {
 
     /// The default host for the current compilation target platform.
     pub fn default_host() -> Host {
-        CoreAudioHost::new()
+        <CoreAudioHost as crate::traits::HostTrait>::new()
             .expect("the default host should always be available")
             .into()
     }
@@ -935,7 +948,6 @@ mod platform_impl {
     ))]
     use crate::host::audioworklet::Host as AudioWorkletHost;
     use crate::host::webaudio::Host as WebAudioHost;
-    use crate::traits::HostTrait as _;
 
     impl_platform_host!(
         WebAudio => WebAudioHost,
@@ -951,11 +963,13 @@ mod platform_impl {
     /// where `AudioContext` is unavailable.
     pub fn default_host() -> Host {
         assert!(
-            WebAudioHost::is_available(),
+            <WebAudioHost as crate::traits::HostTrait>::is_available(),
             "WebAudio is not available in this context; \
              AudioContext requires a Window (not a Worker or Service Worker)"
         );
-        WebAudioHost::new().unwrap().into()
+        <WebAudioHost as crate::traits::HostTrait>::new()
+            .unwrap()
+            .into()
     }
 }
 
@@ -976,7 +990,7 @@ mod platform_impl {
 
     /// The default host for the current compilation target platform.
     pub fn default_host() -> Host {
-        WasapiHost::new()
+        <WasapiHost as crate::traits::HostTrait>::new()
             .expect("the default host should always be available")
             .into()
     }
@@ -992,12 +1006,13 @@ mod platform_impl {
 
     /// The default host for the current compilation target platform.
     pub fn default_host() -> Host {
-        AAudioHost::new()
+        <AAudioHost as crate::traits::HostTrait>::new()
             .expect("the default host should always be available")
             .into()
     }
 }
 
+// A compilation on a platform with no known host backends
 #[cfg(not(any(
     windows,
     target_os = "linux",
@@ -1013,16 +1028,28 @@ mod platform_impl {
     ),
 )))]
 mod platform_impl {
+    #[cfg(feature = "custom")]
+    use crate::host::custom::Host as CustomHost;
+    #[cfg(not(feature = "custom"))]
     use crate::host::null::Host as NullHost;
 
     impl_platform_host!(
-        Null => NullHost,
-        #[cfg(feature = "custom")] Custom => super::CustomHost,
+        #[cfg(not(feature = "custom"))] Null => NullHost,
+        #[cfg(feature = "custom")] Custom => CustomHost,
     );
 
     /// The default host for the current compilation target platform.
+    #[cfg(feature = "custom")]
+    pub fn default_host() -> Host {
+        <CustomHost as crate::traits::HostTrait>::new()
+            .expect("the default host should always be available")
+            .into()
+    }
+
+    /// The default host for the current compilation target platform.
+    #[cfg(not(feature = "custom"))]
     pub fn default_host() -> Host {
-        NullHost::new()
+        <NullHost as crate::traits::HostTrait>::new()
             .expect("the default host should always be available")
             .into()
     }
diff --git a/src/traits.rs b/src/traits.rs
index beeff09d2..69b5e65e7 100644
--- a/src/traits.rs
+++ b/src/traits.rs
@@ -48,6 +48,10 @@ pub trait HostTrait {
     /// Whether or not the host is available on the system.
     fn is_available() -> bool;
 
+    fn new() -> Result<Self, Error>
+    where
+        Self: Sized;
+
     /// An iterator yielding all [`Device`](DeviceTrait)s currently available to the host on the system.
     ///
     /// Can be empty if the system does not support audio in general.