diff --git a/src/cli.rs b/src/cli.rs
index 09050b4a..866457e9 100644
--- a/src/cli.rs
+++ b/src/cli.rs
@@ -191,10 +191,11 @@ pub enum CliBackend {
     Metal,
 }
 
-#[derive(ValueEnum, Debug, Copy, Clone, Hash)]
+#[derive(ValueEnum, Debug, Copy, Clone, Hash, Default)]
 pub enum CliLogLevel {
     Trace,
     Debug,
+    #[default]
     Info,
     Warn,
     Error,
@@ -212,12 +213,6 @@ impl Into<Level> for CliLogLevel {
     }
 }
 
-impl Default for CliLogLevel {
-    fn default() -> Self {
-        Self::Info
-    }
-}
-
 #[derive(Args, Debug)]
 pub struct GenerateArgs {
     /// The shell to generate completions for
diff --git a/src/cli/idle.rs b/src/cli/idle.rs
index 21ea21ad..3fe6443c 100644
--- a/src/cli/idle.rs
+++ b/src/cli/idle.rs
@@ -9,9 +9,10 @@ use {
     std::{cell::Cell, rc::Rc},
 };
 
-#[derive(Subcommand, Debug)]
+#[derive(Subcommand, Debug, Default)]
 pub enum IdleCmd {
     /// Print the idle status.
+    #[default]
     Status,
     /// Set the idle interval.
     Set(IdleSetArgs),
@@ -19,12 +20,6 @@ pub enum IdleCmd {
     SetGracePeriod(IdleSetGracePeriodArgs),
 }
 
-impl Default for IdleCmd {
-    fn default() -> Self {
-        Self::Status
-    }
-}
-
 #[derive(Args, Debug)]
 pub struct IdleSetArgs {
     /// The interval of inactivity after which to disable the screens.
diff --git a/src/ifs/wl_surface/x_surface/xwindow.rs b/src/ifs/wl_surface/x_surface/xwindow.rs
index 4c29833d..d4d44c0d 100644
--- a/src/ifs/wl_surface/x_surface/xwindow.rs
+++ b/src/ifs/wl_surface/x_surface/xwindow.rs
@@ -31,20 +31,15 @@ use {
     thiserror::Error,
 };
 
-#[derive(Copy, Clone, Debug, Eq, PartialEq)]
+#[derive(Copy, Clone, Debug, Eq, PartialEq, Default)]
 pub enum XInputModel {
     None,
+    #[default]
     Passive,
     Local,
     Global,
 }
 
-impl Default for XInputModel {
-    fn default() -> Self {
-        Self::Passive
-    }
-}
-
 #[derive(Default, Debug)]
 pub struct IcccmHints {
     pub flags: Cell<i32>,
diff --git a/src/it/test_mem.rs b/src/it/test_mem.rs
index edd6bedb..3ff49cd5 100644
--- a/src/it/test_mem.rs
+++ b/src/it/test_mem.rs
@@ -61,7 +61,7 @@ fn map(fd: c::c_int, size: usize) -> Result<*const [Cell<u8>], TestError> {
         if res == c::MAP_FAILED {
             bail!("Could not map memory: {}", OsError::default());
         }
-        Ok(std::slice::from_raw_parts(res as _, size))
+        Ok(ptr::slice_from_raw_parts(res as _, size))
     }
 }
 
diff --git a/src/main.rs b/src/main.rs
index cd516e3f..c7354044 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -24,7 +24,6 @@
     clippy::unnecessary_unwrap,
     clippy::needless_return,
     clippy::missing_safety_doc,
-    clippy::collapsible_if,
     clippy::mut_from_ref,
     clippy::bool_comparison,
     clippy::collapsible_match,
diff --git a/src/rect/region.rs b/src/rect/region.rs
index fa2dbf69..bc1613c4 100644
--- a/src/rect/region.rs
+++ b/src/rect/region.rs
@@ -234,18 +234,13 @@ where
     }
 }
 
-#[derive(Copy, Clone, Eq, PartialEq, Debug)]
+#[derive(Copy, Clone, Eq, PartialEq, Debug, Default)]
 enum BuilderOp {
+    #[default]
     Add,
     Sub,
 }
 
-impl Default for BuilderOp {
-    fn default() -> Self {
-        Self::Add
-    }
-}
-
 #[derive(Debug)]
 pub struct RegionBuilder {
     base: Rc<Region>,
diff --git a/src/utils/mmap.rs b/src/utils/mmap.rs
index de4db910..eeae5af7 100644
--- a/src/utils/mmap.rs
+++ b/src/utils/mmap.rs
@@ -20,7 +20,7 @@ pub fn mmap(
         Err(OsError::default())
     } else {
         Ok(Mmapped {
-            ptr: unsafe { std::slice::from_raw_parts(res.cast(), len) },
+            ptr: ptr::slice_from_raw_parts(res.cast(), len),
         })
     }
 }