diff --git a/logos-codegen/src/generator/fork.rs b/logos-codegen/src/generator/fork.rs
index 0f8eeec2..11d4eab2 100644
--- a/logos-codegen/src/generator/fork.rs
+++ b/logos-codegen/src/generator/fork.rs
@@ -10,7 +10,7 @@ use crate::util::ToIdent;
 
 type Targets = Map<NodeId, Vec<Range>>;
 
-impl<'a> Generator<'a> {
+impl Generator<'_> {
     pub fn generate_fork(&mut self, this: NodeId, fork: &Fork, mut ctx: Context) -> TokenStream {
         let mut targets: Targets = Map::default();
 
diff --git a/logos-codegen/src/generator/leaf.rs b/logos-codegen/src/generator/leaf.rs
index 04a6e983..0841a4ff 100644
--- a/logos-codegen/src/generator/leaf.rs
+++ b/logos-codegen/src/generator/leaf.rs
@@ -5,7 +5,7 @@ use crate::generator::{Context, Generator};
 use crate::leaf::{Callback, Leaf};
 use crate::util::MaybeVoid;
 
-impl<'a> Generator<'a> {
+impl Generator<'_> {
     pub fn generate_leaf(&mut self, leaf: &Leaf, mut ctx: Context) -> TokenStream {
         let bump = ctx.bump();
 
diff --git a/logos-codegen/src/generator/rope.rs b/logos-codegen/src/generator/rope.rs
index 2c3e5dd2..ae3b07ad 100644
--- a/logos-codegen/src/generator/rope.rs
+++ b/logos-codegen/src/generator/rope.rs
@@ -4,7 +4,7 @@ use quote::quote;
 use crate::generator::{Context, Generator};
 use crate::graph::Rope;
 
-impl<'a> Generator<'a> {
+impl Generator<'_> {
     pub fn generate_rope(&mut self, rope: &Rope, mut ctx: Context) -> TokenStream {
         let miss = ctx.miss(rope.miss.first(), self);
         let read = ctx.read(rope.pattern.len());
diff --git a/logos-codegen/src/graph/fork.rs b/logos-codegen/src/graph/fork.rs
index 75142466..6b59836b 100644
--- a/logos-codegen/src/graph/fork.rs
+++ b/logos-codegen/src/graph/fork.rs
@@ -122,7 +122,7 @@ pub struct ForkIter<'a> {
     lut: &'a [Option<NodeId>; 256],
 }
 
-impl<'a> Iterator for ForkIter<'a> {
+impl Iterator for ForkIter<'_> {
     type Item = (Range, NodeId);
 
     fn next(&mut self) -> Option<Self::Item> {
diff --git a/src/source.rs b/src/source.rs
index 37e5c6a4..5d7d85d8 100644
--- a/src/source.rs
+++ b/src/source.rs
@@ -241,8 +241,10 @@ where
     T: Deref,
     <T as Deref>::Target: Source,
 {
-    type Slice<'a> = <T::Target as Source>::Slice<'a>
-        where T: 'a;
+    type Slice<'a>
+        = <T::Target as Source>::Slice<'a>
+    where
+        T: 'a;
 
     fn len(&self) -> usize {
         self.deref().len()
@@ -304,7 +306,7 @@ pub trait Chunk<'source>: Sized + Copy + PartialEq + Eq {
     fn from_slice(s: &'source [u8]) -> Option<Self>;
 }
 
-impl<'source> Chunk<'source> for u8 {
+impl Chunk<'_> for u8 {
     const SIZE: usize = 1;
 
     #[inline]
diff --git a/tests/tests/source.rs b/tests/tests/source.rs
index c31d2d28..58e77279 100644
--- a/tests/tests/source.rs
+++ b/tests/tests/source.rs
@@ -6,7 +6,10 @@ use logos_derive::Logos;
 struct RefSource<'s, S: ?Sized + Source>(&'s S);
 
 impl<'s, S: ?Sized + Source> Source for RefSource<'s, S> {
-    type Slice<'a> = S::Slice<'a> where 's: 'a;
+    type Slice<'a>
+        = S::Slice<'a>
+    where
+        's: 'a;
 
     fn len(&self) -> usize {
         self.0.len()