diff --git a/client/src/main.rs b/client/src/main.rs
index 909739f..04cd38a 100644
--- a/client/src/main.rs
+++ b/client/src/main.rs
@@ -657,8 +657,7 @@ fn add_peer(interface: &InterfaceName, opts: AddPeerOpts) -> Result<(), Error> {
         let peer: Peer = api.http_form("POST", "/admin/peers", peer_request)?;
         let server_peer = peers.iter().find(|p| p.id == 1).unwrap();
         prompts::write_peer_invitation(
-            &mut target_file,
-            &target_path,
+            (&mut target_file, &target_path),
             interface,
             &peer,
             server_peer,
@@ -688,7 +687,7 @@ fn rename_peer(interface: &InterfaceName, opts: RenamePeerOpts) -> Result<(), Er
             .filter(|p| p.name == old_name)
             .map(|p| p.id)
             .next()
-            .ok_or(anyhow!("Peer not found."))?;
+            .ok_or_else(|| anyhow!("Peer not found."))?;
 
         let _ = api.http_form("PUT", &format!("/admin/peers/{}", id), peer_request)?;
         log::info!("Peer renamed.");
@@ -728,11 +727,11 @@ fn add_association(interface: &InterfaceName, opts: AddAssociationOpts) -> Resul
         let cidr1 = cidrs
             .iter()
             .find(|c| &c.name == cidr1)
-            .ok_or(anyhow!("can't find cidr '{}'", cidr1))?;
+            .ok_or_else(|| anyhow!("can't find cidr '{}'", cidr1))?;
         let cidr2 = cidrs
             .iter()
             .find(|c| &c.name == cidr2)
-            .ok_or(anyhow!("can't find cidr '{}'", cidr2))?;
+            .ok_or_else(|| anyhow!("can't find cidr '{}'", cidr2))?;
         (cidr1, cidr2)
     } else if let Some((cidr1, cidr2)) = prompts::add_association(&cidrs[..])? {
         (cidr1, cidr2)
@@ -889,7 +888,7 @@ fn show(
         let me = peers
             .iter()
             .find(|p| p.public_key == device_info.public_key.as_ref().unwrap().to_base64())
-            .ok_or(anyhow!("missing peer info"))?;
+            .ok_or_else(|| anyhow!("missing peer info"))?;
 
         let mut peer_states = device_info
             .peers
diff --git a/client/src/util.rs b/client/src/util.rs
index 3684c76..310fbe8 100644
--- a/client/src/util.rs
+++ b/client/src/util.rs
@@ -3,7 +3,7 @@ use colored::*;
 use indoc::eprintdoc;
 use log::{Level, LevelFilter};
 use serde::{de::DeserializeOwned, Serialize};
-use shared::{interface_config::ServerInfo, WrappedIoError, INNERNET_PUBKEY_HEADER};
+use shared::{interface_config::ServerInfo, INNERNET_PUBKEY_HEADER};
 use std::{io, time::Duration};
 use ureq::{Agent, AgentBuilder};
 
diff --git a/server/src/initialize.rs b/server/src/initialize.rs
index 23cafdc..1b4e20d 100644
--- a/server/src/initialize.rs
+++ b/server/src/initialize.rs
@@ -140,7 +140,8 @@ pub fn init_wizard(conf: &ServerConfig, opts: InitializeOpts) -> Result<(), Erro
     let endpoint: Endpoint = if let Some(endpoint) = opts.external_endpoint {
         endpoint
     } else if opts.auto_external_endpoint {
-        let ip = publicip::get_any(Preference::Ipv4).ok_or(anyhow!("couldn't get external IP"))?;
+        let ip = publicip::get_any(Preference::Ipv4)
+            .ok_or_else(|| anyhow!("couldn't get external IP"))?;
         SocketAddr::new(ip, 51820).into()
     } else {
         prompts::ask_endpoint()?
diff --git a/server/src/main.rs b/server/src/main.rs
index 038209e..baeb399 100644
--- a/server/src/main.rs
+++ b/server/src/main.rs
@@ -308,8 +308,7 @@ fn add_peer(
 
         let server_peer = DatabasePeer::get(&conn, 1)?;
         prompts::write_peer_invitation(
-            &mut target_file,
-            &target_path,
+            (&mut target_file, &target_path),
             interface,
             &peer,
             &*server_peer,
@@ -339,7 +338,7 @@ fn rename_peer(
         let mut db_peer = DatabasePeer::list(&conn)?
             .into_iter()
             .find(|p| p.name == old_name)
-            .ok_or(anyhow!("Peer not found."))?;
+            .ok_or_else(|| anyhow!("Peer not found."))?;
         let _peer = db_peer.update(&conn, peer_request)?;
     } else {
         println!("exited without creating peer.");
diff --git a/shared/src/prompts.rs b/shared/src/prompts.rs
index 306c491..a3e4d80 100644
--- a/shared/src/prompts.rs
+++ b/shared/src/prompts.rs
@@ -80,7 +80,7 @@ pub fn add_cidr(cidrs: &[Cidr], request: &AddCidrOpts) -> Result<Option<CidrCont
         cidrs
             .iter()
             .find(|cidr| &cidr.name == parent_name)
-            .ok_or(anyhow!("No parent CIDR with that name exists."))?
+            .ok_or_else(|| anyhow!("No parent CIDR with that name exists."))?
     } else {
         choose_cidr(cidrs, "Parent CIDR")?
     };
@@ -219,7 +219,7 @@ pub fn add_peer(
         leaves
             .iter()
             .find(|cidr| &cidr.name == parent_name)
-            .ok_or(anyhow!("No eligible CIDR with that name exists."))?
+            .ok_or_else(|| anyhow!("No eligible CIDR with that name exists."))?
     } else {
         choose_cidr(&leaves[..], "Eligible CIDRs for peer")?
     };
@@ -384,8 +384,7 @@ pub fn enable_or_disable_peer(peers: &[Peer], enable: bool) -> Result<Option<Pee
 
 /// Confirm and write a innernet invitation file after a peer has been created.
 pub fn write_peer_invitation(
-    target_file: &mut File,
-    target_path: &str,
+    target_file: (&mut File, &str),
     network_name: &InterfaceName,
     peer: &Peer,
     server_peer: &Peer,
@@ -410,7 +409,7 @@ pub fn write_peer_invitation(
         },
     };
 
-    peer_invitation.write_to(target_file, true, None)?;
+    peer_invitation.write_to(target_file.0, true, None)?;
 
     println!(
         "\nPeer \"{}\" added\n\
@@ -418,7 +417,7 @@ pub fn write_peer_invitation(
          Please send it to them securely (eg. via magic-wormhole) \
          to bootstrap them onto the network.",
         peer.name.bold(),
-        target_path.bold()
+        target_file.1.bold()
     );
 
     Ok(())
diff --git a/wgctrl-rs/src/backends/userspace.rs b/wgctrl-rs/src/backends/userspace.rs
index 2b3768c..adb237d 100644
--- a/wgctrl-rs/src/backends/userspace.rs
+++ b/wgctrl-rs/src/backends/userspace.rs
@@ -249,7 +249,7 @@ pub fn get_by_name(name: &InterfaceName) -> Result<Device, io::Error> {
         match reader.read_line(&mut buf)? {
             0 | 1 if buf == "\n" => break,
             _ => {
-                parser.add_line(&buf.trim_end())?;
+                parser.add_line(buf.trim_end())?;
                 buf.clear();
             },
         };
diff --git a/wgctrl-rs/src/device.rs b/wgctrl-rs/src/device.rs
index af96966..c9c0128 100644
--- a/wgctrl-rs/src/device.rs
+++ b/wgctrl-rs/src/device.rs
@@ -420,8 +420,8 @@ impl DeviceUpdate {
     pub fn apply(self, iface: &InterfaceName, backend: Backend) -> io::Result<()> {
         match backend {
             #[cfg(target_os = "linux")]
-            Backend::Kernel => backends::kernel::apply(&self, &iface),
-            Backend::Userspace => backends::userspace::apply(&self, &iface),
+            Backend::Kernel => backends::kernel::apply(&self, iface),
+            Backend::Userspace => backends::userspace::apply(&self, iface),
         }
     }
 }