diff --git a/benches/cases/rewriting.rs b/benches/cases/rewriting.rs
index 3010f0b8..39fdc4d6 100644
--- a/benches/cases/rewriting.rs
+++ b/benches/cases/rewriting.rs
@@ -1,5 +1,5 @@
-use lol_html::html_content::*;
-use lol_html::*;
+use lol_html::html_content::ContentType;
+use lol_html::{element, Settings};
 
 define_group!(
     "Rewriting",
diff --git a/benches/cases/selector_matching.rs b/benches/cases/selector_matching.rs
index e9a3ad29..40d99cbe 100644
--- a/benches/cases/selector_matching.rs
+++ b/benches/cases/selector_matching.rs
@@ -1,4 +1,4 @@
-use lol_html::*;
+use lol_html::{element, Settings};
 
 define_group!(
     "Selector matching",
diff --git a/js-api/src/lib.rs b/js-api/src/lib.rs
index 7cc9bce1..8d0eec99 100644
--- a/js-api/src/lib.rs
+++ b/js-api/src/lib.rs
@@ -15,6 +15,7 @@ struct Anchor<'r> {
 }
 
 impl<'r> Anchor<'r> {
+    #[inline]
     pub fn new(poisoned: Rc<Cell<bool>>) -> Self {
         Anchor {
             poisoned,
diff --git a/src/base/bytes.rs b/src/base/bytes.rs
index fbcf510e..7f9f3d2b 100644
--- a/src/base/bytes.rs
+++ b/src/base/bytes.rs
@@ -180,6 +180,7 @@ impl Debug for Bytes<'_> {
 impl Deref for Bytes<'_> {
     type Target = [u8];
 
+    #[inline]
     fn deref(&self) -> &[u8] {
         &self.0
     }
diff --git a/src/base/encoding.rs b/src/base/encoding.rs
index 4413632e..2f9504d2 100644
--- a/src/base/encoding.rs
+++ b/src/base/encoding.rs
@@ -256,12 +256,14 @@ pub struct SharedEncoding {
 }
 
 impl SharedEncoding {
-    pub fn new(encoding: AsciiCompatibleEncoding) -> SharedEncoding {
-        SharedEncoding {
+    #[must_use]
+    pub fn new(encoding: AsciiCompatibleEncoding) -> Self {
+        Self {
             encoding: Arc::new(AtomicUsize::new(encoding_to_index(encoding))),
         }
     }
 
+    #[must_use]
     pub fn get(&self) -> &'static Encoding {
         let encoding = self.encoding.load(Ordering::Relaxed);
         ALL_ENCODINGS[encoding]
diff --git a/src/html/local_name.rs b/src/html/local_name.rs
index 8ce38b8a..e99e895c 100644
--- a/src/html/local_name.rs
+++ b/src/html/local_name.rs
@@ -30,12 +30,14 @@ pub struct LocalNameHash(Option<u64>);
 
 impl LocalNameHash {
     #[inline]
-    pub fn new() -> Self {
-        LocalNameHash(Some(0))
+    #[must_use]
+    pub const fn new() -> Self {
+        Self(Some(0))
     }
 
     #[inline]
-    pub fn is_empty(&self) -> bool {
+    #[must_use]
+    pub const fn is_empty(&self) -> bool {
         self.0.is_none()
     }
 
@@ -75,7 +77,7 @@ impl LocalNameHash {
 impl From<&str> for LocalNameHash {
     #[inline]
     fn from(string: &str) -> Self {
-        let mut hash = LocalNameHash::new();
+        let mut hash = Self::new();
 
         for ch in string.bytes() {
             hash.update(ch);
@@ -106,6 +108,7 @@ pub enum LocalName<'i> {
 
 impl<'i> LocalName<'i> {
     #[inline]
+    #[must_use]
     pub fn new(input: &'i Bytes<'i>, range: Range, hash: LocalNameHash) -> Self {
         if hash.is_empty() {
             LocalName::Bytes(input.slice(range))
@@ -115,6 +118,7 @@ impl<'i> LocalName<'i> {
     }
 
     #[inline]
+    #[must_use]
     pub fn into_owned(self) -> LocalName<'static> {
         match self {
             LocalName::Bytes(b) => LocalName::Bytes(b.into_owned()),
@@ -150,7 +154,7 @@ impl PartialEq<Tag> for LocalName<'_> {
 impl PartialEq<LocalName<'_>> for LocalName<'_> {
     #[inline]
     fn eq(&self, other: &LocalName<'_>) -> bool {
-        use LocalName::*;
+        use LocalName::{Bytes, Hash};
 
         match (self, other) {
             (Hash(s), Hash(o)) => s == o,
diff --git a/src/html/namespace.rs b/src/html/namespace.rs
index 661631d3..10b73342 100644
--- a/src/html/namespace.rs
+++ b/src/html/namespace.rs
@@ -8,8 +8,8 @@ pub enum Namespace {
 
 impl Namespace {
     #[inline]
-    pub fn uri(self) -> &'static str {
-        use Namespace::*;
+    pub const fn uri(self) -> &'static str {
+        use Namespace::{Html, MathML, Svg};
 
         // NOTE: https://infra.spec.whatwg.org/#namespaces
         match self {
diff --git a/src/html/text_type.rs b/src/html/text_type.rs
index cfa826d8..c34dd587 100644
--- a/src/html/text_type.rs
+++ b/src/html/text_type.rs
@@ -41,8 +41,9 @@ impl TextType {
     ///
     /// [HTML entities]: https://developer.mozilla.org/en-US/docs/Glossary/Entity
     #[inline]
+    #[must_use]
     pub fn allows_html_entities(self) -> bool {
-        self == TextType::Data || self == TextType::RCData
+        self == Self::Data || self == Self::RCData
     }
 }
 
diff --git a/src/lib.rs b/src/lib.rs
index eda92b76..909c08c7 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -16,7 +16,8 @@
 //! [Cloudflare Workers]: https://www.cloudflare.com/en-gb/products/cloudflare-workers/
 //! [`HtmlRewriter`]: struct.HtmlRewriter.html
 //! [`rewrite_str`]: fn.rewrite_str.html
-
+#![allow(clippy::default_trait_access)]
+#![allow(clippy::module_name_repetitions)]
 #![cfg_attr(not(any(feature = "integration_test", test)), warn(missing_docs))]
 
 #[macro_use]
@@ -151,8 +152,9 @@ pub mod test_utils {
     }
 
     impl Output {
+        #[must_use]
         pub fn new(encoding: &'static Encoding) -> Self {
-            Output {
+            Self {
                 bytes: Vec::default(),
                 encoding,
                 finalizing_chunk_received: false,
@@ -174,7 +176,7 @@ pub mod test_utils {
     }
 
     impl From<Output> for String {
-        fn from(output: Output) -> String {
+        fn from(output: Output) -> Self {
             assert!(
                 output.finalizing_chunk_received,
                 "Finalizing chunk for the output hasn't been received."
diff --git a/src/memory/arena.rs b/src/memory/arena.rs
index 1423b639..00bedf43 100644
--- a/src/memory/arena.rs
+++ b/src/memory/arena.rs
@@ -12,7 +12,7 @@ impl Arena {
     pub fn new(limiter: SharedMemoryLimiter, preallocated_size: usize) -> Self {
         limiter.preallocate(preallocated_size);
 
-        Arena {
+        Self {
             limiter,
             data: Vec::with_capacity(preallocated_size),
         }
diff --git a/src/memory/limited_vec.rs b/src/memory/limited_vec.rs
index f9fd618c..a228c79e 100644
--- a/src/memory/limited_vec.rs
+++ b/src/memory/limited_vec.rs
@@ -14,7 +14,7 @@ pub struct LimitedVec<T> {
 
 impl<T> LimitedVec<T> {
     pub fn new(limiter: SharedMemoryLimiter) -> Self {
-        LimitedVec {
+        Self {
             vec: vec![],
             limiter,
         }
@@ -122,7 +122,7 @@ mod tests {
     #[test]
     fn max_limit() {
         let limiter = SharedMemoryLimiter::new(2);
-        let mut vector: LimitedVec<u8> = LimitedVec::new(limiter.clone());
+        let mut vector: LimitedVec<u8> = LimitedVec::new(limiter);
 
         vector.push(1).unwrap();
         vector.push(2).unwrap();
diff --git a/src/memory/limiter.rs b/src/memory/limiter.rs
index 7d367cb5..3547e7cc 100644
--- a/src/memory/limiter.rs
+++ b/src/memory/limiter.rs
@@ -17,8 +17,9 @@ pub struct SharedMemoryLimiter {
 }
 
 impl SharedMemoryLimiter {
-    pub fn new(max: usize) -> SharedMemoryLimiter {
-        SharedMemoryLimiter {
+    #[must_use]
+    pub fn new(max: usize) -> Self {
+        Self {
             current_usage: Arc::new(AtomicUsize::new(0)),
             max,
         }
diff --git a/src/parser/lexer/actions.rs b/src/parser/lexer/actions.rs
index 3ac16cf5..c806c13e 100644
--- a/src/parser/lexer/actions.rs
+++ b/src/parser/lexer/actions.rs
@@ -2,7 +2,7 @@ use super::*;
 use crate::parser::state_machine::StateMachineActions;
 
 use NonTagContentTokenOutline::*;
-use TagTokenOutline::*;
+use TagTokenOutline::{EndTag, StartTag};
 
 // NOTE: use macro instead of the function to make borrow
 // checker happy with range construction inside match arm
@@ -233,8 +233,8 @@ impl<S: LexemeSink> StateMachineActions for Lexer<S> {
     #[inline]
     fn finish_tag_name(&mut self, _context: &mut ParserContext<S>, _input: &[u8]) -> ActionResult {
         match self.current_tag_token {
-            Some(StartTag { ref mut name, .. }) | Some(EndTag { ref mut name, .. }) => {
-                *name = get_token_part_range!(self)
+            Some(StartTag { ref mut name, .. } | EndTag { ref mut name, .. }) => {
+                *name = get_token_part_range!(self);
             }
             _ => unreachable!("Tag should exist at this point"),
         }
@@ -246,12 +246,14 @@ impl<S: LexemeSink> StateMachineActions for Lexer<S> {
     fn update_tag_name_hash(&mut self, _context: &mut ParserContext<S>, input: &[u8]) {
         if let Some(ch) = input.get(self.pos()).copied() {
             match self.current_tag_token {
-                Some(StartTag {
-                    ref mut name_hash, ..
-                })
-                | Some(EndTag {
-                    ref mut name_hash, ..
-                }) => name_hash.update(ch),
+                Some(
+                    StartTag {
+                        ref mut name_hash, ..
+                    }
+                    | EndTag {
+                        ref mut name_hash, ..
+                    },
+                ) => name_hash.update(ch),
                 _ => unreachable!("Tag should exist at this point"),
             }
         }
diff --git a/src/parser/lexer/conditions.rs b/src/parser/lexer/conditions.rs
index 34625177..cf75f341 100644
--- a/src/parser/lexer/conditions.rs
+++ b/src/parser/lexer/conditions.rs
@@ -3,6 +3,7 @@ use crate::parser::state_machine::StateMachineConditions;
 
 impl<S: LexemeSink> StateMachineConditions for Lexer<S> {
     #[inline]
+    #[must_use]
     fn is_appropriate_end_tag(&self) -> bool {
         match self.current_tag_token {
             Some(TagTokenOutline::EndTag { name_hash, .. }) => {
@@ -13,6 +14,7 @@ impl<S: LexemeSink> StateMachineConditions for Lexer<S> {
     }
 
     #[inline]
+    #[must_use]
     fn cdata_allowed(&self) -> bool {
         self.cdata_allowed
     }
diff --git a/src/parser/lexer/lexeme/token_outline.rs b/src/parser/lexer/lexeme/token_outline.rs
index 97eead4d..96a49f03 100644
--- a/src/parser/lexer/lexeme/token_outline.rs
+++ b/src/parser/lexer/lexeme/token_outline.rs
@@ -53,13 +53,13 @@ impl Align for TagTokenOutline {
     #[inline]
     fn align(&mut self, offset: usize) {
         match self {
-            TagTokenOutline::StartTag {
+            Self::StartTag {
                 name, attributes, ..
             } => {
                 name.align(offset);
                 attributes.as_mut_slice().align(offset);
             }
-            TagTokenOutline::EndTag { name, .. } => name.align(offset),
+            Self::EndTag { name, .. } => name.align(offset),
         }
     }
 }
@@ -68,8 +68,8 @@ impl Align for NonTagContentTokenOutline {
     #[inline]
     fn align(&mut self, offset: usize) {
         match self {
-            NonTagContentTokenOutline::Comment(text) => text.align(offset),
-            NonTagContentTokenOutline::Doctype {
+            Self::Comment(text) => text.align(offset),
+            Self::Doctype {
                 name,
                 public_id,
                 system_id,
diff --git a/src/parser/lexer/mod.rs b/src/parser/lexer/mod.rs
index f2c8d88e..e5b19f44 100644
--- a/src/parser/lexer/mod.rs
+++ b/src/parser/lexer/mod.rs
@@ -43,15 +43,17 @@ pub struct Lexer<S: LexemeSink> {
 }
 
 impl<S: LexemeSink> Lexer<S> {
+    #[inline]
+    #[must_use]
     pub fn new() -> Self {
-        Lexer {
+        Self {
             next_pos: 0,
             is_last_input: false,
             lexeme_start: 0,
             token_part_start: 0,
             is_state_enter: true,
             cdata_allowed: false,
-            state: Lexer::data_state,
+            state: Self::data_state,
             current_tag_token: None,
             current_non_tag_content_token: None,
             current_attr: None,
@@ -133,8 +135,9 @@ impl<S: LexemeSink> Lexer<S> {
     }
 
     #[inline]
+    #[must_use]
     fn create_lexeme_with_raw<'i, T>(
-        &mut self,
+        &self,
         input: &'i [u8],
         token: T,
         raw_end: usize,
@@ -150,22 +153,16 @@ impl<S: LexemeSink> Lexer<S> {
     }
 
     #[inline]
-    fn create_lexeme_with_raw_inclusive<'i, T>(
-        &mut self,
-        input: &'i [u8],
-        token: T,
-    ) -> Lexeme<'i, T> {
+    #[must_use]
+    fn create_lexeme_with_raw_inclusive<'i, T>(&self, input: &'i [u8], token: T) -> Lexeme<'i, T> {
         let raw_end = self.pos() + 1;
 
         self.create_lexeme_with_raw(input, token, raw_end)
     }
 
     #[inline]
-    fn create_lexeme_with_raw_exclusive<'i, T>(
-        &mut self,
-        input: &'i [u8],
-        token: T,
-    ) -> Lexeme<'i, T> {
+    #[must_use]
+    fn create_lexeme_with_raw_exclusive<'i, T>(&self, input: &'i [u8], token: T) -> Lexeme<'i, T> {
         let raw_end = self.pos();
 
         self.create_lexeme_with_raw(input, token, raw_end)
diff --git a/src/parser/mod.rs b/src/parser/mod.rs
index 058e56a5..ddf8e428 100644
--- a/src/parser/mod.rs
+++ b/src/parser/mod.rs
@@ -43,13 +43,15 @@ pub struct Parser<S: ParserOutputSink> {
 }
 
 impl<S: ParserOutputSink> Parser<S> {
+    #[inline]
+    #[must_use]
     pub fn new(output_sink: S, initial_directive: ParserDirective, strict: bool) -> Self {
         let context = ParserContext {
             output_sink,
             tree_builder_simulator: TreeBuilderSimulator::new(strict),
         };
 
-        Parser {
+        Self {
             lexer: Lexer::new(),
             tag_scanner: TagScanner::new(),
             current_directive: initial_directive,
diff --git a/src/parser/state_machine/mod.rs b/src/parser/state_machine/mod.rs
index 8376d25c..e6fa5fab 100644
--- a/src/parser/state_machine/mod.rs
+++ b/src/parser/state_machine/mod.rs
@@ -18,8 +18,8 @@ pub enum FeedbackDirective {
 
 impl FeedbackDirective {
     #[inline]
-    pub fn take(&mut self) -> FeedbackDirective {
-        mem::replace(self, FeedbackDirective::None)
+    pub fn take(&mut self) -> Self {
+        mem::replace(self, Self::None)
     }
 }
 
@@ -30,9 +30,9 @@ impl Debug for FeedbackDirective {
             f,
             "{}",
             match self {
-                FeedbackDirective::ApplyUnhandledFeedback(_) => "ApplyPendingFeedback",
-                FeedbackDirective::Skip => "Skip",
-                FeedbackDirective::None => "None",
+                Self::ApplyUnhandledFeedback(_) => "ApplyPendingFeedback",
+                Self::Skip => "Skip",
+                Self::None => "None",
             }
         )
     }
@@ -56,7 +56,7 @@ pub enum ActionError {
 impl From<ParsingAmbiguityError> for ActionError {
     #[cold]
     fn from(err: ParsingAmbiguityError) -> Self {
-        ActionError::RewritingError(RewritingError::ParsingAmbiguity(err))
+        Self::RewritingError(RewritingError::ParsingAmbiguity(err))
     }
 }
 
@@ -218,7 +218,7 @@ pub trait StateMachine: StateMachineActions + StateMachineConditions {
         let consumed_byte_count = self.get_consumed_byte_count(input);
 
         if !self.is_last_input() {
-            self.adjust_for_next_input()
+            self.adjust_for_next_input();
         }
 
         self.set_pos(self.pos() - consumed_byte_count);
diff --git a/src/parser/state_machine/syntax_dsl/arm_pattern/mod.rs b/src/parser/state_machine/syntax_dsl/arm_pattern/mod.rs
index 89048f56..97b2d430 100644
--- a/src/parser/state_machine/syntax_dsl/arm_pattern/mod.rs
+++ b/src/parser/state_machine/syntax_dsl/arm_pattern/mod.rs
@@ -5,14 +5,14 @@ macro_rules! arm_pattern {
     ( | $cb_args:tt |>
          alpha => $actions:tt
     ) => {
-        state_body!(@callback | $cb_args |> Some(b'a'..=b'z') | Some(b'A'..=b'Z') => $actions);
+        state_body!(@callback | $cb_args |> Some(b'a'..=b'z' | b'A'..=b'Z') => $actions);
     };
 
     ( | $cb_args:tt |>
         whitespace => $actions:tt
     ) => {
         state_body!(@callback | $cb_args |>
-            Some(b' ') | Some(b'\n') | Some(b'\r') | Some(b'\t') | Some(b'\x0C') => $actions
+            Some(b' ' | b'\n' | b'\r' | b'\t' | b'\x0C') => $actions
         );
     };
 
diff --git a/src/parser/tag_scanner/conditions.rs b/src/parser/tag_scanner/conditions.rs
index 3cb77370..b7e298f6 100644
--- a/src/parser/tag_scanner/conditions.rs
+++ b/src/parser/tag_scanner/conditions.rs
@@ -3,11 +3,13 @@ use crate::parser::state_machine::StateMachineConditions;
 
 impl<S: TagHintSink> StateMachineConditions for TagScanner<S> {
     #[inline]
+    #[must_use]
     fn is_appropriate_end_tag(&self) -> bool {
         self.tag_name_hash == self.last_start_tag_name_hash
     }
 
     #[inline]
+    #[must_use]
     fn cdata_allowed(&self) -> bool {
         self.cdata_allowed
     }
diff --git a/src/parser/tag_scanner/mod.rs b/src/parser/tag_scanner/mod.rs
index 0259db4e..0a0fc68e 100644
--- a/src/parser/tag_scanner/mod.rs
+++ b/src/parser/tag_scanner/mod.rs
@@ -50,7 +50,7 @@ pub struct TagScanner<S: TagHintSink> {
 
 impl<S: TagHintSink> TagScanner<S> {
     pub fn new() -> Self {
-        TagScanner {
+        Self {
             next_pos: 0,
             is_last_input: false,
             tag_start: None,
@@ -61,7 +61,7 @@ impl<S: TagHintSink> TagScanner<S> {
             last_start_tag_name_hash: LocalNameHash::default(),
             is_state_enter: true,
             cdata_allowed: false,
-            state: TagScanner::data_state,
+            state: Self::data_state,
             closing_quote: b'"',
             pending_text_type_change: None,
             last_text_type: TextType::Data,
@@ -128,12 +128,14 @@ impl<S: TagHintSink> TagScanner<S> {
 
     #[inline]
     fn take_feedback_directive(&mut self) -> FeedbackDirective {
-        match self.pending_text_type_change.take() {
-            Some(text_type) => FeedbackDirective::ApplyUnhandledFeedback(
-                TreeBuilderFeedback::SwitchTextType(text_type),
-            ),
-            None => FeedbackDirective::Skip,
-        }
+        self.pending_text_type_change
+            .take()
+            .map(|text_type| {
+                FeedbackDirective::ApplyUnhandledFeedback(TreeBuilderFeedback::SwitchTextType(
+                    text_type,
+                ))
+            })
+            .unwrap_or(FeedbackDirective::Skip)
     }
 }
 
diff --git a/src/parser/tree_builder_simulator/ambiguity_guard.rs b/src/parser/tree_builder_simulator/ambiguity_guard.rs
index 448db7bc..c0cb30b4 100644
--- a/src/parser/tree_builder_simulator/ambiguity_guard.rs
+++ b/src/parser/tree_builder_simulator/ambiguity_guard.rs
@@ -138,7 +138,7 @@ pub struct AmbiguityGuard {
 
 impl Default for AmbiguityGuard {
     fn default() -> Self {
-        AmbiguityGuard {
+        Self {
             state: State::Default,
         }
     }
@@ -180,7 +180,7 @@ impl AmbiguityGuard {
             State::InOrAfterFrameset => {
                 // NOTE: <noframes> is allowed in and after <frameset>.
                 if tag_name != Tag::Noframes {
-                    assert_not_ambigious_text_type_switch(tag_name)?
+                    assert_not_ambigious_text_type_switch(tag_name)?;
                 }
             }
         }
diff --git a/src/parser/tree_builder_simulator/mod.rs b/src/parser/tree_builder_simulator/mod.rs
index d5a908af..47aa2f38 100644
--- a/src/parser/tree_builder_simulator/mod.rs
+++ b/src/parser/tree_builder_simulator/mod.rs
@@ -17,7 +17,7 @@ use self::ambiguity_guard::AmbiguityGuard;
 use crate::base::Bytes;
 use crate::html::{LocalNameHash, Namespace, Tag, TextType};
 use crate::parser::{TagLexeme, TagTokenOutline};
-use TagTokenOutline::*;
+use TagTokenOutline::{EndTag, StartTag};
 
 pub use self::ambiguity_guard::ParsingAmbiguityError;
 
@@ -37,7 +37,7 @@ pub enum TreeBuilderFeedback {
 impl From<TextType> for TreeBuilderFeedback {
     #[inline]
     fn from(text_type: TextType) -> Self {
-        TreeBuilderFeedback::SwitchTextType(text_type)
+        Self::SwitchTextType(text_type)
     }
 }
 
@@ -120,8 +120,10 @@ pub struct TreeBuilderSimulator {
 }
 
 impl TreeBuilderSimulator {
+    #[inline]
+    #[must_use]
     pub fn new(strict: bool) -> Self {
-        let mut simulator = TreeBuilderSimulator {
+        let mut simulator = Self {
             ns_stack: Vec::with_capacity(DEFAULT_NS_STACK_CAPACITY),
             current_ns: Namespace::Html,
             ambiguity_guard: AmbiguityGuard::default(),
@@ -252,7 +254,7 @@ impl TreeBuilderSimulator {
             // to decide on foreign context exit
             return request_lexeme(|this, lexeme| {
                 expect_tag!(lexeme, StartTag { ref attributes, .. } => {
-                    for attr in attributes.iter() {
+                    for attr in attributes {
                         let name = lexeme.part(attr.name);
 
                         if eq_case_insensitive(&name, b"color")
@@ -281,7 +283,7 @@ impl TreeBuilderSimulator {
                     let name = lexeme.part(name);
 
                     if !self_closing && eq_case_insensitive(&name, b"annotation-xml") {
-                        for attr in attributes.iter() {
+                        for attr in attributes {
                             let name = lexeme.part(attr.name);
                             let value = lexeme.part(attr.value);
 
diff --git a/src/rewritable_units/document_end.rs b/src/rewritable_units/document_end.rs
index a853f869..9958bd01 100644
--- a/src/rewritable_units/document_end.rs
+++ b/src/rewritable_units/document_end.rs
@@ -15,6 +15,8 @@ pub struct DocumentEnd<'a> {
 }
 
 impl<'a> DocumentEnd<'a> {
+    #[inline]
+    #[must_use]
     pub(crate) fn new(output_sink: &'a mut dyn OutputSink, encoding: &'static Encoding) -> Self {
         DocumentEnd {
             output_sink,
@@ -49,7 +51,7 @@ impl<'a> DocumentEnd<'a> {
     #[inline]
     pub fn append(&mut self, content: &str, content_type: ContentType) {
         content_to_bytes(content, content_type, self.encoding, &mut |c: &[u8]| {
-            self.output_sink.handle_chunk(c)
+            self.output_sink.handle_chunk(c);
         });
     }
 }
@@ -91,7 +93,7 @@ mod tests {
             end.append("<div></div>", ContentType::Html);
         });
 
-        assert_eq!(output, "<div></div>")
+        assert_eq!(output, "<div></div>");
     }
 
     #[test]
diff --git a/src/rewritable_units/element.rs b/src/rewritable_units/element.rs
index bdea4305..89616606 100644
--- a/src/rewritable_units/element.rs
+++ b/src/rewritable_units/element.rs
@@ -45,6 +45,8 @@ pub struct Element<'r, 't, H: HandlerTypes = LocalHandlerTypes> {
 }
 
 impl<'r, 't, H: HandlerTypes> Element<'r, 't, H> {
+    #[inline]
+    #[must_use]
     pub(crate) fn new(start_tag: &'r mut StartTag<'t>, can_have_content: bool) -> Self {
         let encoding = start_tag.encoding();
 
@@ -75,10 +77,9 @@ impl<'r, 't, H: HandlerTypes> Element<'r, 't, H> {
                     // encoding then encoding_rs replaces it with a numeric
                     // character reference. Character references are not
                     // supported in tag names, so we need to bail.
-                    match Bytes::from_str_without_replacements(name, self.encoding) {
-                        Ok(name) => Ok(name.into_owned()),
-                        Err(_) => Err(TagNameError::UnencodableCharacter),
-                    }
+                    Bytes::from_str_without_replacements(name, self.encoding)
+                        .map_err(|_| TagNameError::UnencodableCharacter)
+                        .map(Bytes::into_owned)
                 }
             }
             None => Err(TagNameError::Empty),
@@ -102,12 +103,14 @@ impl<'r, 't, H: HandlerTypes> Element<'r, 't, H> {
 
     /// Returns the tag name of the element.
     #[inline]
+    #[must_use]
     pub fn tag_name(&self) -> String {
         self.start_tag.name()
     }
 
     /// Returns the tag name of the element, preserving its case.
     #[inline]
+    #[must_use]
     pub fn tag_name_preserve_case(&self) -> String {
         self.start_tag.name_preserve_case()
     }
@@ -128,6 +131,7 @@ impl<'r, 't, H: HandlerTypes> Element<'r, 't, H> {
 
     /// Whether the element is explicitly self-closing, e.g. `<foo />`.
     #[inline]
+    #[must_use]
     pub fn is_self_closing(&self) -> bool {
         self.start_tag.self_closing()
     }
@@ -136,6 +140,7 @@ impl<'r, 't, H: HandlerTypes> Element<'r, 't, H> {
     /// element](https://html.spec.whatwg.org/multipage/syntax.html#void-elements) or has a
     /// self-closing tag (eg, `<foo />`).
     #[inline]
+    #[must_use]
     pub fn can_have_content(&self) -> bool {
         self.can_have_content
     }
@@ -144,12 +149,14 @@ impl<'r, 't, H: HandlerTypes> Element<'r, 't, H> {
     ///
     /// [namespace URI]: https://developer.mozilla.org/en-US/docs/Web/API/Element/namespaceURI
     #[inline]
+    #[must_use]
     pub fn namespace_uri(&self) -> &'static str {
         self.start_tag.namespace_uri()
     }
 
     /// Returns an immutable collection of element's attributes.
     #[inline]
+    #[must_use]
     pub fn attributes(&self) -> &[Attribute<'t>] {
         self.start_tag.attributes()
     }
@@ -158,6 +165,7 @@ impl<'r, 't, H: HandlerTypes> Element<'r, 't, H> {
     ///
     /// Returns `None` if the element doesn't have an attribute with the `name`.
     #[inline]
+    #[must_use]
     pub fn get_attribute(&self, name: &str) -> Option<String> {
         let name = name.to_ascii_lowercase();
 
@@ -172,6 +180,7 @@ impl<'r, 't, H: HandlerTypes> Element<'r, 't, H> {
 
     /// Returns `true` if the element has an attribute with `name`.
     #[inline]
+    #[must_use]
     pub fn has_attribute(&self, name: &str) -> bool {
         let name = name.to_ascii_lowercase();
 
@@ -471,6 +480,7 @@ impl<'r, 't, H: HandlerTypes> Element<'r, 't, H> {
 
     /// Returns `true` if the element has been removed or replaced with some content.
     #[inline]
+    #[must_use]
     pub fn removed(&self) -> bool {
         self.start_tag.mutations.removed()
     }
@@ -640,7 +650,7 @@ mod tests {
     fn forbidden_characters_in_tag_name() {
         rewrite_element(b"<div>", UTF_8, "div", |el| {
             for &ch in &[' ', '\n', '\r', '\t', '\x0C', '/', '>'] {
-                let err = el.set_tag_name(&format!("foo{}bar", ch)).unwrap_err();
+                let err = el.set_tag_name(&format!("foo{ch}bar")).unwrap_err();
 
                 assert_eq!(err, TagNameError::ForbiddenCharacter(ch));
             }
@@ -702,7 +712,7 @@ mod tests {
     fn forbidden_characters_in_attr_name() {
         rewrite_element(b"<div>", UTF_8, "div", |el| {
             for &ch in &[' ', '\n', '\r', '\t', '\x0C', '/', '>', '='] {
-                let err = el.set_attribute(&format!("foo{}bar", ch), "").unwrap_err();
+                let err = el.set_attribute(&format!("foo{ch}bar"), "").unwrap_err();
 
                 assert_eq!(err, AttributeNameError::ForbiddenCharacter(ch));
             }
@@ -1085,7 +1095,7 @@ mod tests {
             }));
         };
 
-        let res = rewrite_element("<div>foo</div>".as_bytes(), UTF_8, "div", handler);
+        let res = rewrite_element(b"<div>foo</div>", UTF_8, "div", handler);
 
         assert_eq!(res, "<div>fooXY</div>");
     }
@@ -1188,7 +1198,7 @@ mod tests {
                 el.remove_attribute("a1");
             });
 
-            assert_eq!(output, r#"<img/>"#);
+            assert_eq!(output, r"<img/>");
         }
 
         #[test]
diff --git a/src/rewritable_units/tokens/attributes.rs b/src/rewritable_units/tokens/attributes.rs
index d235f8c8..108a6be7 100644
--- a/src/rewritable_units/tokens/attributes.rs
+++ b/src/rewritable_units/tokens/attributes.rs
@@ -41,6 +41,8 @@ pub struct Attribute<'i> {
 }
 
 impl<'i> Attribute<'i> {
+    #[inline]
+    #[must_use]
     fn new(name: Bytes<'i>, value: Bytes<'i>, raw: Bytes<'i>, encoding: &'static Encoding) -> Self {
         Attribute {
             name,
@@ -69,10 +71,9 @@ impl<'i> Attribute<'i> {
             // encoding then encoding_rs replaces it with a numeric
             // character reference. Character references are not
             // supported in attribute names, so we need to bail.
-            match Bytes::from_str_without_replacements(name, encoding) {
-                Ok(name) => Ok(name.into_owned()),
-                Err(_) => Err(AttributeNameError::UnencodableCharacter),
-            }
+            Bytes::from_str_without_replacements(name, encoding)
+                .map_err(|_| AttributeNameError::UnencodableCharacter)
+                .map(Bytes::into_owned)
         }
     }
 
@@ -92,18 +93,21 @@ impl<'i> Attribute<'i> {
 
     /// Returns the name of the attribute.
     #[inline]
+    #[must_use]
     pub fn name(&self) -> String {
         self.name.as_lowercase_string(self.encoding)
     }
 
     /// Returns the name of the attribute, preserving its case.
     #[inline]
+    #[must_use]
     pub fn name_preserve_case(&self) -> String {
         self.name.as_string(self.encoding)
     }
 
     /// Returns the value of the attribute.
     #[inline]
+    #[must_use]
     pub fn value(&self) -> String {
         self.value.as_string(self.encoding)
     }
@@ -148,6 +152,8 @@ pub struct Attributes<'i> {
 }
 
 impl<'i> Attributes<'i> {
+    #[inline]
+    #[must_use]
     pub(super) fn new(
         input: &'i Bytes<'i>,
         attribute_buffer: &'i AttributeBuffer,
diff --git a/src/rewritable_units/tokens/capturer/mod.rs b/src/rewritable_units/tokens/capturer/mod.rs
index 1e1348ea..0b4e254c 100644
--- a/src/rewritable_units/tokens/capturer/mod.rs
+++ b/src/rewritable_units/tokens/capturer/mod.rs
@@ -29,15 +29,17 @@ pub enum TokenCapturerEvent<'i> {
 
 type CapturerEventHandler<'h> = &'h mut dyn FnMut(TokenCapturerEvent) -> Result<(), RewritingError>;
 
-pub struct TokenCapturer {
+pub(crate) struct TokenCapturer {
     encoding: SharedEncoding,
     text_decoder: TextDecoder,
     capture_flags: TokenCaptureFlags,
 }
 
 impl TokenCapturer {
+    #[inline]
+    #[must_use]
     pub fn new(capture_flags: TokenCaptureFlags, encoding: SharedEncoding) -> Self {
-        TokenCapturer {
+        Self {
             encoding: SharedEncoding::clone(&encoding),
             text_decoder: TextDecoder::new(encoding),
             capture_flags,
@@ -45,7 +47,8 @@ impl TokenCapturer {
     }
 
     #[inline]
-    pub fn has_captures(&self) -> bool {
+    #[must_use]
+    pub const fn has_captures(&self) -> bool {
         !self.capture_flags.is_empty()
     }
 
diff --git a/src/rewritable_units/tokens/capturer/text_decoder.rs b/src/rewritable_units/tokens/capturer/text_decoder.rs
index a068ca21..7c73f615 100644
--- a/src/rewritable_units/tokens/capturer/text_decoder.rs
+++ b/src/rewritable_units/tokens/capturer/text_decoder.rs
@@ -22,8 +22,10 @@ pub struct TextDecoder {
 }
 
 impl TextDecoder {
+    #[inline]
+    #[must_use]
     pub fn new(encoding: SharedEncoding) -> Self {
-        TextDecoder {
+        Self {
             encoding,
             pending_text_streaming_decoder: None,
             // TODO make adjustable
diff --git a/src/rewritable_units/tokens/comment.rs b/src/rewritable_units/tokens/comment.rs
index 935d3f5a..808f0a1a 100644
--- a/src/rewritable_units/tokens/comment.rs
+++ b/src/rewritable_units/tokens/comment.rs
@@ -31,6 +31,8 @@ pub struct Comment<'i> {
 }
 
 impl<'i> Comment<'i> {
+    #[inline]
+    #[must_use]
     pub(super) fn new_token(
         text: Bytes<'i>,
         raw: Bytes<'i>,
@@ -47,6 +49,7 @@ impl<'i> Comment<'i> {
 
     /// Returns the text of the comment.
     #[inline]
+    #[must_use]
     pub fn text(&self) -> String {
         self.text.as_string(self.encoding)
     }
@@ -177,12 +180,13 @@ impl<'i> Comment<'i> {
 
     /// Returns `true` if the comment has been replaced or removed.
     #[inline]
+    #[must_use]
     pub fn removed(&self) -> bool {
         self.mutations.removed()
     }
 
     #[inline]
-    fn raw(&self) -> Option<&Bytes> {
+    const fn raw(&self) -> Option<&Bytes> {
         self.raw.as_ref()
     }
 
diff --git a/src/rewritable_units/tokens/doctype.rs b/src/rewritable_units/tokens/doctype.rs
index 912aa5df..ab9678e2 100644
--- a/src/rewritable_units/tokens/doctype.rs
+++ b/src/rewritable_units/tokens/doctype.rs
@@ -43,6 +43,8 @@ pub struct Doctype<'i> {
 }
 
 impl<'i> Doctype<'i> {
+    #[inline]
+    #[must_use]
     pub(super) fn new_token(
         name: Option<Bytes<'i>>,
         public_id: Option<Bytes<'i>>,
@@ -66,6 +68,7 @@ impl<'i> Doctype<'i> {
 
     /// The name of the doctype.
     #[inline]
+    #[must_use]
     pub fn name(&self) -> Option<String> {
         self.name
             .as_ref()
@@ -74,12 +77,14 @@ impl<'i> Doctype<'i> {
 
     /// The public identifier of the doctype.
     #[inline]
+    #[must_use]
     pub fn public_id(&self) -> Option<String> {
         self.public_id.as_ref().map(|i| i.as_string(self.encoding))
     }
 
     /// The system identifier of the doctype.
     #[inline]
+    #[must_use]
     pub fn system_id(&self) -> Option<String> {
         self.system_id.as_ref().map(|i| i.as_string(self.encoding))
     }
@@ -93,11 +98,12 @@ impl<'i> Doctype<'i> {
     /// Removes the doctype.
     #[inline]
     pub fn remove(&mut self) {
-        self.removed = true
+        self.removed = true;
     }
 
     /// Returns `true` if the doctype has been replaced or removed.
     #[inline]
+    #[must_use]
     pub fn removed(&self) -> bool {
         self.removed
     }
diff --git a/src/rewritable_units/tokens/end_tag.rs b/src/rewritable_units/tokens/end_tag.rs
index b3c8adba..dee300c8 100644
--- a/src/rewritable_units/tokens/end_tag.rs
+++ b/src/rewritable_units/tokens/end_tag.rs
@@ -15,6 +15,8 @@ pub struct EndTag<'i> {
 }
 
 impl<'i> EndTag<'i> {
+    #[inline]
+    #[must_use]
     pub(super) fn new_token(
         name: Bytes<'i>,
         raw: Bytes<'i>,
@@ -30,12 +32,14 @@ impl<'i> EndTag<'i> {
 
     /// Returns the name of the tag.
     #[inline]
+    #[must_use]
     pub fn name(&self) -> String {
         self.name.as_lowercase_string(self.encoding)
     }
 
     /// Returns the name of the tag, preserving its case.
     #[inline]
+    #[must_use]
     pub fn name_preserve_case(&self) -> String {
         self.name.as_string(self.encoding)
     }
@@ -50,7 +54,7 @@ impl<'i> EndTag<'i> {
     /// Sets the name of the tag by encoding the given string.
     #[inline]
     pub fn set_name_str(&mut self, name: String) {
-        self.set_name(Bytes::from_string(name, self.encoding))
+        self.set_name(Bytes::from_string(name, self.encoding));
     }
 
     /// Inserts `content` before the end tag.
@@ -84,7 +88,7 @@ impl<'i> EndTag<'i> {
     }
 
     #[inline]
-    fn raw(&self) -> Option<&Bytes> {
+    const fn raw(&self) -> Option<&Bytes> {
         self.raw.as_ref()
     }
 
diff --git a/src/rewritable_units/tokens/start_tag.rs b/src/rewritable_units/tokens/start_tag.rs
index ee2dd2d1..00c4d5e0 100644
--- a/src/rewritable_units/tokens/start_tag.rs
+++ b/src/rewritable_units/tokens/start_tag.rs
@@ -20,6 +20,8 @@ pub struct StartTag<'i> {
 }
 
 impl<'i> StartTag<'i> {
+    #[inline]
+    #[must_use]
     pub(super) fn new_token(
         name: Bytes<'i>,
         attributes: Attributes<'i>,
@@ -41,7 +43,7 @@ impl<'i> StartTag<'i> {
 
     #[inline]
     #[doc(hidden)]
-    pub fn encoding(&self) -> &'static Encoding {
+    pub const fn encoding(&self) -> &'static Encoding {
         self.encoding
     }
 
@@ -135,7 +137,7 @@ impl<'i> StartTag<'i> {
     }
 
     #[inline]
-    fn raw(&self) -> Option<&Bytes> {
+    const fn raw(&self) -> Option<&Bytes> {
         self.raw.as_ref()
     }
 
diff --git a/src/rewritable_units/tokens/text_chunk.rs b/src/rewritable_units/tokens/text_chunk.rs
index de01caf4..ee164e96 100644
--- a/src/rewritable_units/tokens/text_chunk.rs
+++ b/src/rewritable_units/tokens/text_chunk.rs
@@ -67,6 +67,8 @@ pub struct TextChunk<'i> {
 }
 
 impl<'i> TextChunk<'i> {
+    #[inline]
+    #[must_use]
     pub(super) fn new_token(
         text: &'i str,
         text_type: TextType,
@@ -85,6 +87,7 @@ impl<'i> TextChunk<'i> {
 
     /// Returns the textual content of the chunk.
     #[inline]
+    #[must_use]
     pub fn as_str(&self) -> &str {
         &self.text
     }
@@ -136,6 +139,7 @@ impl<'i> TextChunk<'i> {
     /// ).unwrap();
     /// ```
     #[inline]
+    #[must_use]
     pub fn text_type(&self) -> TextType {
         self.text_type
     }
@@ -144,6 +148,7 @@ impl<'i> TextChunk<'i> {
     ///
     /// Note that last chunk can have empty textual content.
     #[inline]
+    #[must_use]
     pub fn last_in_text_node(&self) -> bool {
         self.last_in_text_node
     }
@@ -258,12 +263,14 @@ impl<'i> TextChunk<'i> {
 
     /// Returns `true` if the text chunk has been replaced or removed.
     #[inline]
+    #[must_use]
     pub fn removed(&self) -> bool {
         self.mutations.removed()
     }
 
     #[inline]
-    fn raw(&self) -> Option<&Bytes> {
+    #[allow(clippy::unused_self)]
+    const fn raw(&self) -> Option<&Bytes> {
         None
     }
 
@@ -335,7 +342,7 @@ mod tests {
     fn in_place_text_modifications() {
         use super::super::Token;
 
-        let encoding = Encoding::for_label_no_replacement("utf-8".as_bytes()).unwrap();
+        let encoding = Encoding::for_label_no_replacement(b"utf-8").unwrap();
         let Token::TextChunk(mut chunk) =
             TextChunk::new_token("original text", TextType::PlainText, true, encoding)
         else {
diff --git a/src/rewriter/handlers_dispatcher.rs b/src/rewriter/handlers_dispatcher.rs
index eb1ffee9..c96723be 100644
--- a/src/rewriter/handlers_dispatcher.rs
+++ b/src/rewriter/handlers_dispatcher.rs
@@ -22,7 +22,7 @@ struct HandlerVec<H> {
 
 impl<H> Default for HandlerVec<H> {
     fn default() -> Self {
-        HandlerVec {
+        Self {
             items: Vec::default(),
             user_count: 0,
         }
@@ -68,7 +68,7 @@ impl<H> HandlerVec<H> {
         &mut self,
         mut cb: impl FnMut(&mut H) -> HandlerResult,
     ) -> HandlerResult {
-        for item in self.items.iter_mut() {
+        for item in &mut self.items {
             if item.user_count > 0 {
                 cb(&mut item.handler)?;
             }
@@ -82,7 +82,7 @@ impl<H> HandlerVec<H> {
         &mut self,
         mut cb: impl FnMut(&mut H) -> HandlerResult,
     ) -> HandlerResult {
-        for item in self.items.iter_mut() {
+        for item in &mut self.items {
             if item.user_count > 0 {
                 cb(&mut item.handler)?;
                 self.user_count -= item.user_count;
diff --git a/src/rewriter/mod.rs b/src/rewriter/mod.rs
index 4f54a828..9998abe7 100644
--- a/src/rewriter/mod.rs
+++ b/src/rewriter/mod.rs
@@ -29,6 +29,7 @@ pub struct AsciiCompatibleEncoding(&'static Encoding);
 
 impl AsciiCompatibleEncoding {
     /// Returns `Some` if `Encoding` is ascii-compatible, or `None` otherwise.
+    #[must_use]
     pub fn new(encoding: &'static Encoding) -> Option<Self> {
         if encoding.is_ascii_compatible() {
             Some(Self(encoding))
@@ -37,14 +38,15 @@ impl AsciiCompatibleEncoding {
         }
     }
 
-    fn from_mimetype(mime: &Mime) -> Option<AsciiCompatibleEncoding> {
+    fn from_mimetype(mime: &Mime) -> Option<Self> {
         mime.get_param("charset")
             .and_then(|cs| Encoding::for_label_no_replacement(cs.as_str().as_bytes()))
-            .and_then(AsciiCompatibleEncoding::new)
+            .and_then(Self::new)
     }
 
     /// Returns the most commonly used UTF-8 encoding.
-    pub fn utf_8() -> AsciiCompatibleEncoding {
+    #[must_use]
+    pub fn utf_8() -> Self {
         Self(encoding_rs::UTF_8)
     }
 }
@@ -279,7 +281,7 @@ fn handler_adjust_charset_on_meta_tag<'h, H: HandlerTypes>(
             .and_then(AsciiCompatibleEncoding::from_mimetype);
 
         if let Some(charset) = attr_charset.or(attr_http_equiv) {
-            encoding.set(charset)
+            encoding.set(charset);
         }
 
         Ok(())
@@ -455,7 +457,7 @@ mod tests {
 
     #[test]
     fn doctype_info() {
-        for &enc in ASCII_COMPATIBLE_ENCODINGS.iter() {
+        for &enc in &ASCII_COMPATIBLE_ENCODINGS {
             let mut doctypes = Vec::default();
 
             {
@@ -502,7 +504,7 @@ mod tests {
 
     #[test]
     fn rewrite_start_tags() {
-        for &enc in ASCII_COMPATIBLE_ENCODINGS.iter() {
+        for &enc in &ASCII_COMPATIBLE_ENCODINGS {
             let actual: String = {
                 let mut output = Output::new(enc);
 
@@ -553,7 +555,7 @@ mod tests {
 
     #[test]
     fn rewrite_document_content() {
-        for &enc in ASCII_COMPATIBLE_ENCODINGS.iter() {
+        for &enc in &ASCII_COMPATIBLE_ENCODINGS {
             let actual: String = {
                 let mut output = Output::new(enc);
 
@@ -685,7 +687,7 @@ mod tests {
                 .as_bytes()
                 .to_vec(),
             vec![0xd5, 0xec, 0xb3, 0xcb, 0xdc],
-            r#"!</body></html>"#.as_bytes().to_vec(),
+            br"!</body></html>".to_vec(),
         ]
         .into_iter()
         .concat();
@@ -739,7 +741,7 @@ mod tests {
         let html: Vec<u8> = [
             r#"<meta http-equiv="content-type" content="text/html; charset=windows-1251"><html><head></head><body>I love "#.as_bytes().to_vec(),
             vec![0xd5, 0xec, 0xb3, 0xcb, 0xdc],
-            r#"!</body></html>"#.as_bytes().to_vec(),
+            br"!</body></html>".to_vec(),
         ].into_iter().concat();
 
         let expected: Vec<u8> = html
@@ -860,9 +862,9 @@ mod tests {
 
                 let mut err = None;
 
-                for chunk in chunks.iter() {
+                for chunk in &chunks {
                     match rewriter.write(chunk.as_bytes()) {
-                        Ok(_) => (),
+                        Ok(()) => (),
                         Err(e) => {
                             err = Some(e);
                             break;
@@ -872,7 +874,7 @@ mod tests {
 
                 if err.is_none() {
                     match rewriter.end() {
-                        Ok(_) => (),
+                        Ok(()) => (),
                         Err(e) => err = Some(e),
                     }
                 }
diff --git a/src/rewriter/rewrite_controller.rs b/src/rewriter/rewrite_controller.rs
index 928b8bd4..1868d765 100644
--- a/src/rewriter/rewrite_controller.rs
+++ b/src/rewriter/rewrite_controller.rs
@@ -81,7 +81,7 @@ impl<'h, H: HandlerTypes> TransformController for HtmlRewriteController<'h, H> {
                 let mut match_handler = |m| self.handlers_dispatcher.start_matching(m);
 
                 match vm.exec_for_start_tag(local_name, ns, &mut match_handler) {
-                    Ok(_) => Ok(self.get_capture_flags()),
+                    Ok(()) => Ok(self.get_capture_flags()),
                     Err(VmError::InfoRequest(req)) => Self::respond_to_aux_info_request(req),
                     Err(VmError::MemoryLimitExceeded(e)) => Err(DispatcherError::RewritingError(
                         RewritingError::MemoryLimitExceeded(e),
diff --git a/src/rewriter/settings.rs b/src/rewriter/settings.rs
index d7f8e84f..514e4cd7 100644
--- a/src/rewriter/settings.rs
+++ b/src/rewriter/settings.rs
@@ -66,7 +66,7 @@ impl HandlerTypes for LocalHandlerTypes {
     }
 
     fn new_element_handler<'h>(
-        handler: impl IntoHandler<ElementHandlerSend<'h, LocalHandlerTypes>>,
+        handler: impl IntoHandler<ElementHandlerSend<'h, Self>>,
     ) -> Self::ElementHandler<'h> {
         handler.into_handler()
     }
@@ -88,7 +88,7 @@ impl HandlerTypes for SendHandlerTypes {
     type DoctypeHandler<'h> = DoctypeHandlerSend<'h>;
     type CommentHandler<'h> = CommentHandlerSend<'h>;
     type TextHandler<'h> = TextHandlerSend<'h>;
-    type ElementHandler<'h> = ElementHandlerSend<'h, SendHandlerTypes>;
+    type ElementHandler<'h> = ElementHandlerSend<'h, Self>;
     type EndTagHandler<'h> = EndTagHandlerSend<'h>;
     type EndHandler<'h> = EndHandlerSend<'h>;
 
@@ -99,7 +99,7 @@ impl HandlerTypes for SendHandlerTypes {
     }
 
     fn new_element_handler<'h>(
-        handler: impl IntoHandler<ElementHandlerSend<'h, SendHandlerTypes>>,
+        handler: impl IntoHandler<ElementHandlerSend<'h, Self>>,
     ) -> Self::ElementHandler<'h> {
         handler.into_handler()
     }
@@ -263,6 +263,7 @@ impl<'h, H: HandlerTypes> Default for ElementContentHandlers<'h, H> {
 impl<'h, H: HandlerTypes> ElementContentHandlers<'h, H> {
     /// Sets a handler for elements matched by a selector.
     #[inline]
+    #[must_use]
     pub fn element(mut self, handler: impl IntoHandler<H::ElementHandler<'h>>) -> Self {
         self.element = Some(handler.into_handler());
 
@@ -271,6 +272,7 @@ impl<'h, H: HandlerTypes> ElementContentHandlers<'h, H> {
 
     /// Sets a handler for HTML comments in the inner content of elements matched by a selector.
     #[inline]
+    #[must_use]
     pub fn comments(mut self, handler: impl IntoHandler<H::CommentHandler<'h>>) -> Self {
         self.comments = Some(handler.into_handler());
 
@@ -279,6 +281,7 @@ impl<'h, H: HandlerTypes> ElementContentHandlers<'h, H> {
 
     /// Sets a handler for text chunks in the inner content of elements matched by a selector.
     #[inline]
+    #[must_use]
     pub fn text(mut self, handler: impl IntoHandler<H::TextHandler<'h>>) -> Self {
         self.text = Some(handler.into_handler());
 
@@ -328,6 +331,7 @@ impl<'h, H: HandlerTypes> DocumentContentHandlers<'h, H> {
     ///
     /// [document type declaration]: https://developer.mozilla.org/en-US/docs/Glossary/Doctype
     #[inline]
+    #[must_use]
     pub fn doctype(mut self, handler: impl IntoHandler<H::DoctypeHandler<'h>>) -> Self {
         self.doctype = Some(handler.into_handler());
 
@@ -336,6 +340,7 @@ impl<'h, H: HandlerTypes> DocumentContentHandlers<'h, H> {
 
     /// Sets a handler for all HTML comments present in the input HTML markup.
     #[inline]
+    #[must_use]
     pub fn comments(mut self, handler: impl IntoHandler<H::CommentHandler<'h>>) -> Self {
         self.comments = Some(handler.into_handler());
 
@@ -344,6 +349,7 @@ impl<'h, H: HandlerTypes> DocumentContentHandlers<'h, H> {
 
     /// Sets a handler for all text chunks present in the input HTML markup.
     #[inline]
+    #[must_use]
     pub fn text(mut self, handler: impl IntoHandler<H::TextHandler<'h>>) -> Self {
         self.text = Some(handler.into_handler());
 
@@ -352,6 +358,7 @@ impl<'h, H: HandlerTypes> DocumentContentHandlers<'h, H> {
 
     /// Sets a handler for the document end, which is called after the last chunk is processed.
     #[inline]
+    #[must_use]
     pub fn end(mut self, handler: impl IntoHandler<H::EndHandler<'h>>) -> Self {
         self.end = Some(handler.into_handler());
 
@@ -399,7 +406,7 @@ macro_rules! element {
     ($selector:expr, $handler:expr) => {{
         // Without this rust won't be able to always infer the type of the handler.
         #[inline(always)]
-        fn type_hint<'h, T, H: $crate::HandlerTypes>(h: T) -> T
+        const fn type_hint<'h, T, H: $crate::HandlerTypes>(h: T) -> T
         where
             T: FnMut(&mut $crate::html_content::Element<'_, '_, H>) -> $crate::HandlerResult + 'h,
         {
@@ -481,7 +488,7 @@ macro_rules! comments {
     ($selector:expr, $handler:expr) => {{
         // Without this rust won't be able to always infer the type of the handler.
         #[inline(always)]
-        fn type_hint<T>(h: T) -> T
+        const fn type_hint<T>(h: T) -> T
         where
             T: FnMut(&mut $crate::html_content::Comment) -> $crate::HandlerResult,
         {
@@ -528,7 +535,7 @@ macro_rules! doctype {
     ($handler:expr) => {{
         // Without this rust won't be able to always infer the type of the handler.
         #[inline(always)]
-        fn type_hint<T>(h: T) -> T
+        const fn type_hint<T>(h: T) -> T
         where
             T: FnMut(&mut $crate::html_content::Doctype) -> $crate::HandlerResult,
         {
@@ -569,7 +576,7 @@ macro_rules! doc_text {
     ($handler:expr) => {{
         // Without this rust won't be able to always infer the type of the handler.
         #[inline(always)]
-        fn type_hint<T>(h: T) -> T
+        const fn type_hint<T>(h: T) -> T
         where
             T: FnMut(&mut $crate::html_content::TextChunk) -> $crate::HandlerResult,
         {
@@ -608,7 +615,7 @@ macro_rules! doc_comments {
     ($handler:expr) => {{
         // Without this rust won't be able to always infer the type of the handler.
         #[inline(always)]
-        fn type_hint<T>(h: T) -> T
+        const fn type_hint<T>(h: T) -> T
         where
             T: FnMut(&mut $crate::html_content::Comment) -> $crate::HandlerResult,
         {
@@ -656,7 +663,7 @@ macro_rules! end {
     ($handler:expr) => {{
         // Without this rust won't be able to always infer the type of the handler.
         #[inline(always)]
-        fn type_hint<T>(h: T) -> T
+        const fn type_hint<T>(h: T) -> T
         where
             T: FnOnce(&mut $crate::html_content::DocumentEnd) -> $crate::HandlerResult,
         {
@@ -716,7 +723,7 @@ pub struct MemorySettings {
 impl Default for MemorySettings {
     #[inline]
     fn default() -> Self {
-        MemorySettings {
+        Self {
             preallocated_parsing_buffer_size: 1024,
             max_allowed_memory_usage: usize::MAX,
         }
@@ -725,8 +732,9 @@ impl Default for MemorySettings {
 
 impl MemorySettings {
     /// Create a new [`MemorySettings`] with default values.
-    pub fn new() -> MemorySettings {
-        MemorySettings::default()
+    #[must_use]
+    pub fn new() -> Self {
+        Self::default()
     }
 }
 
@@ -885,6 +893,7 @@ impl Default for Settings<'_, '_, LocalHandlerTypes> {
 impl Settings<'_, '_, LocalHandlerTypes> {
     /// Creates [`Settings`] for non-[`Send`]able [`HtmlRewriter`](crate::HtmlRewriter)s.
     #[inline]
+    #[must_use]
     pub fn new() -> Self {
         Self::new_for_handler_types()
     }
@@ -893,6 +902,7 @@ impl Settings<'_, '_, LocalHandlerTypes> {
 impl Settings<'_, '_, SendHandlerTypes> {
     /// Creates [`Settings`] for [`Send`]able [`HtmlRewriter`](crate::HtmlRewriter)s.
     #[inline]
+    #[must_use]
     pub fn new_send() -> Self {
         Self::new_for_handler_types()
     }
@@ -901,6 +911,7 @@ impl Settings<'_, '_, SendHandlerTypes> {
 impl<H: HandlerTypes> Settings<'_, '_, H> {
     /// Creates [`Settings`].
     #[inline]
+    #[must_use]
     pub fn new_for_handler_types() -> Self {
         Settings {
             element_content_handlers: vec![],
@@ -1039,7 +1050,8 @@ impl Default for RewriteStrSettings<'_, '_, LocalHandlerTypes> {
 impl RewriteStrSettings<'_, '_, LocalHandlerTypes> {
     /// Creates [`Settings`] for non-[`Send`]able [`HtmlRewriter`](crate::HtmlRewriter)s.
     #[inline]
-    pub fn new() -> Self {
+    #[must_use]
+    pub const fn new() -> Self {
         Self::new_for_handler_types()
     }
 }
@@ -1047,7 +1059,8 @@ impl RewriteStrSettings<'_, '_, LocalHandlerTypes> {
 impl RewriteStrSettings<'_, '_, SendHandlerTypes> {
     /// Creates [`Settings`] for [`Send`]able [`HtmlRewriter`](crate::HtmlRewriter)s.
     #[inline]
-    pub fn new_send() -> Self {
+    #[must_use]
+    pub const fn new_send() -> Self {
         Self::new_for_handler_types()
     }
 }
@@ -1055,7 +1068,8 @@ impl RewriteStrSettings<'_, '_, SendHandlerTypes> {
 impl<H: HandlerTypes> RewriteStrSettings<'_, '_, H> {
     /// Creates [`RewriteStrSettings`].
     #[inline]
-    pub fn new_for_handler_types() -> Self {
+    #[must_use]
+    pub const fn new_for_handler_types() -> Self {
         RewriteStrSettings {
             element_content_handlers: vec![],
             document_content_handlers: vec![],
diff --git a/src/selectors_vm/ast.rs b/src/selectors_vm/ast.rs
index 6965c55d..685954b6 100644
--- a/src/selectors_vm/ast.rs
+++ b/src/selectors_vm/ast.rs
@@ -14,16 +14,19 @@ pub struct NthChild {
 impl NthChild {
     /// A first child with a step of 0 and an offset of 1
     #[inline]
-    pub fn first() -> Self {
+    #[must_use]
+    pub const fn first() -> Self {
         Self::new(0, 1)
     }
 
     #[inline]
-    pub fn new(step: i32, offset: i32) -> Self {
+    #[must_use]
+    pub const fn new(step: i32, offset: i32) -> Self {
         Self { step, offset }
     }
 
-    pub fn has_index(self, index: i32) -> bool {
+    #[must_use]
+    pub const fn has_index(self, index: i32) -> bool {
         let Self { offset, step } = self;
         // wrap to prevent panic/abort. we won't wrap around anyway, even with a
         // max offset value (i32::MAX) since index is always more than 0
@@ -61,7 +64,8 @@ pub struct AttributeComparisonExpr {
 
 impl AttributeComparisonExpr {
     #[inline]
-    pub fn new(
+    #[must_use]
+    pub const fn new(
         name: String,
         value: String,
         case_sensitivity: ParsedCaseSensitivity,
@@ -119,17 +123,15 @@ impl From<&Component<SelectorImplDescriptor>> for Condition {
     #[inline]
     fn from(component: &Component<SelectorImplDescriptor>) -> Self {
         match component {
-            Component::LocalName(n) => {
-                Condition::OnTagName(OnTagNameExpr::LocalName(n.name.to_owned()))
-            }
+            Component::LocalName(n) => Self::OnTagName(OnTagNameExpr::LocalName(n.name.clone())),
             Component::ExplicitUniversalType | Component::ExplicitAnyNamespace => {
-                Condition::OnTagName(OnTagNameExpr::ExplicitAny)
+                Self::OnTagName(OnTagNameExpr::ExplicitAny)
             }
-            Component::ExplicitNoNamespace => Condition::OnTagName(OnTagNameExpr::Unmatchable),
-            Component::ID(id) => Condition::OnAttributes(OnAttributesExpr::Id(id.to_owned())),
-            Component::Class(c) => Condition::OnAttributes(OnAttributesExpr::Class(c.to_owned())),
+            Component::ExplicitNoNamespace => Self::OnTagName(OnTagNameExpr::Unmatchable),
+            Component::ID(id) => Self::OnAttributes(OnAttributesExpr::Id(id.to_owned())),
+            Component::Class(c) => Self::OnAttributes(OnAttributesExpr::Class(c.to_owned())),
             Component::AttributeInNoNamespaceExists { local_name, .. } => {
-                Condition::OnAttributes(OnAttributesExpr::AttributeExists(local_name.to_owned()))
+                Self::OnAttributes(OnAttributesExpr::AttributeExists(local_name.to_owned()))
             }
             &Component::AttributeInNoNamespace {
                 ref local_name,
@@ -139,9 +141,9 @@ impl From<&Component<SelectorImplDescriptor>> for Condition {
                 never_matches,
             } => {
                 if never_matches {
-                    Condition::OnTagName(OnTagNameExpr::Unmatchable)
+                    Self::OnTagName(OnTagNameExpr::Unmatchable)
                 } else {
-                    Condition::OnAttributes(OnAttributesExpr::AttributeComparisonExpr(
+                    Self::OnAttributes(OnAttributesExpr::AttributeComparisonExpr(
                         AttributeComparisonExpr::new(
                             local_name.to_owned(),
                             value.to_owned(),
@@ -151,17 +153,13 @@ impl From<&Component<SelectorImplDescriptor>> for Condition {
                     ))
                 }
             }
-            Component::FirstChild => {
-                Condition::OnTagName(OnTagNameExpr::NthChild(NthChild::first()))
-            }
+            Component::FirstChild => Self::OnTagName(OnTagNameExpr::NthChild(NthChild::first())),
             &Component::NthChild(a, b) => {
-                Condition::OnTagName(OnTagNameExpr::NthChild(NthChild::new(a, b)))
-            }
-            Component::FirstOfType => {
-                Condition::OnTagName(OnTagNameExpr::NthOfType(NthChild::first()))
+                Self::OnTagName(OnTagNameExpr::NthChild(NthChild::new(a, b)))
             }
+            Component::FirstOfType => Self::OnTagName(OnTagNameExpr::NthOfType(NthChild::first())),
             &Component::NthOfType(a, b) => {
-                Condition::OnTagName(OnTagNameExpr::NthOfType(NthChild::new(a, b)))
+                Self::OnTagName(OnTagNameExpr::NthOfType(NthChild::new(a, b)))
             }
             // NOTE: the rest of the components are explicit namespace or
             // pseudo class-related. Ideally none of them should appear in
@@ -188,8 +186,8 @@ where
     E: PartialEq + Eq + Debug,
 {
     #[inline]
-    fn new(simple_expr: E, negation: bool) -> Self {
-        Expr {
+    const fn new(simple_expr: E, negation: bool) -> Self {
+        Self {
             simple_expr,
             negation,
         }
@@ -207,7 +205,7 @@ fn add_expr_to_list<E>(list: &mut Vec<Expr<E>>, expr: E, negation: bool)
 where
     E: PartialEq + Eq + Debug,
 {
-    list.push(Expr::new(expr, negation))
+    list.push(Expr::new(expr, negation));
 }
 
 impl Predicate {
@@ -236,7 +234,7 @@ where
     P: Hash + Eq,
 {
     fn new(predicate: Predicate) -> Self {
-        AstNode {
+        Self {
             predicate,
             children: Vec::default(),
             descendants: Vec::default(),
@@ -265,19 +263,17 @@ where
         branches: &mut Vec<AstNode<P>>,
         cumulative_node_count: &mut usize,
     ) -> usize {
-        match branches
+        branches
             .iter()
             .enumerate()
             .find(|(_, n)| n.predicate == predicate)
-        {
-            Some((i, _)) => i,
-            None => {
+            .map(|(i, _)| i)
+            .unwrap_or_else(|| {
                 branches.push(AstNode::new(predicate));
                 *cumulative_node_count += 1;
 
                 branches.len() - 1
-            }
-        }
+            })
     }
 
     pub fn add_selector(&mut self, selector: &Selector, payload: P) {
@@ -308,7 +304,7 @@ where
                         ),
                     },
                     Component::Negation(c) => {
-                        c.iter().for_each(|c| predicate.add_component(c, true))
+                        c.iter().for_each(|c| predicate.add_component(c, true));
                     }
                     _ => predicate.add_component(component, false),
                 }
@@ -333,6 +329,7 @@ mod tests {
         };
     }
 
+    #[track_caller]
     fn assert_ast(selectors: &[&str], expected: Ast<usize>) {
         let mut ast = Ast::default();
 
@@ -343,13 +340,14 @@ mod tests {
         assert_eq!(ast, expected);
     }
 
+    #[track_caller]
     fn assert_err(selector: &str, expected_err: SelectorError) {
         assert_eq!(selector.parse::<Selector>().unwrap_err(), expected_err);
     }
 
     #[test]
     fn simple_non_attr_expression() {
-        vec![
+        for (selector, expected) in [
             (
                 "*",
                 Expr {
@@ -378,9 +376,7 @@ mod tests {
                     negation: true,
                 },
             ),
-        ]
-        .into_iter()
-        .for_each(|(selector, expected)| {
+        ] {
             assert_ast(
                 &[selector],
                 Ast {
@@ -396,12 +392,12 @@ mod tests {
                     cumulative_node_count: 1,
                 },
             );
-        });
+        }
     }
 
     #[test]
     fn simple_attr_expression() {
-        vec![
+        for (selector, expected) in [
             (
                 "#foo",
                 Expr {
@@ -521,9 +517,7 @@ mod tests {
                     negation: true,
                 },
             ),
-        ]
-        .into_iter()
-        .for_each(|(selector, expected)| {
+        ] {
             assert_ast(
                 &[selector],
                 Ast {
@@ -539,7 +533,7 @@ mod tests {
                     cumulative_node_count: 1,
                 },
             );
-        });
+        }
     }
 
     #[test]
@@ -667,7 +661,7 @@ mod tests {
                 }],
                 cumulative_node_count: 5,
             },
-        )
+        );
     }
 
     #[test]
diff --git a/src/selectors_vm/attribute_matcher.rs b/src/selectors_vm/attribute_matcher.rs
index 3d2c3e82..5c058f27 100644
--- a/src/selectors_vm/attribute_matcher.rs
+++ b/src/selectors_vm/attribute_matcher.rs
@@ -14,7 +14,7 @@ lazy_static! {
 }
 
 #[inline]
-fn is_attr_whitespace(b: u8) -> bool {
+const fn is_attr_whitespace(b: u8) -> bool {
     b == b' ' || b == b'\n' || b == b'\r' || b == b'\t' || b == b'\x0c'
 }
 
@@ -30,6 +30,7 @@ pub struct AttributeMatcher<'i> {
 
 impl<'i> AttributeMatcher<'i> {
     #[inline]
+    #[must_use]
     pub fn new(input: &'i Bytes<'i>, attributes: &'i AttributeBuffer, ns: Namespace) -> Self {
         AttributeMatcher {
             input,
@@ -59,7 +60,7 @@ impl<'i> AttributeMatcher<'i> {
 
                 true
             })
-            .cloned()
+            .copied()
     }
 
     #[inline]
@@ -69,11 +70,13 @@ impl<'i> AttributeMatcher<'i> {
     }
 
     #[inline]
+    #[must_use]
     pub fn has_attribute(&self, lowercased_name: &Bytes) -> bool {
         self.find(lowercased_name).is_some()
     }
 
     #[inline]
+    #[must_use]
     pub fn has_id(&self, id: &Bytes) -> bool {
         match self.id.borrow_with(|| self.get_value(&ID_ATTR)) {
             Some(actual_id) => actual_id == id,
@@ -82,6 +85,7 @@ impl<'i> AttributeMatcher<'i> {
     }
 
     #[inline]
+    #[must_use]
     pub fn has_class(&self, class_name: &Bytes) -> bool {
         match self.class.borrow_with(|| self.get_value(&CLASS_ATTR)) {
             Some(class) => class
@@ -93,10 +97,7 @@ impl<'i> AttributeMatcher<'i> {
 
     #[inline]
     fn value_matches(&self, name: &Bytes, matcher: impl Fn(Bytes) -> bool) -> bool {
-        match self.get_value(name) {
-            Some(value) => matcher(value),
-            None => false,
-        }
+        self.get_value(name).is_some_and(matcher)
     }
 
     #[inline]
@@ -176,9 +177,8 @@ impl<'i> AttributeMatcher<'i> {
                 .case_sensitivity
                 .to_unconditional(self.is_html_element);
 
-            let (first_byte, rest) = match operand.value.split_first() {
-                Some((&f, r)) => (f, r),
-                None => return false,
+            let Some((&first_byte, rest)) = operand.value.split_first() else {
+                return false;
             };
 
             let first_byte_searcher: Box<dyn Fn(_) -> _> = match case_sensitivity {
diff --git a/src/selectors_vm/compiler.rs b/src/selectors_vm/compiler.rs
index de8190dc..2348dbe6 100644
--- a/src/selectors_vm/compiler.rs
+++ b/src/selectors_vm/compiler.rs
@@ -197,8 +197,9 @@ impl<P: 'static> Compiler<P>
 where
     P: PartialEq + Eq + Copy + Debug + Hash,
 {
+    #[must_use]
     pub fn new(encoding: &'static Encoding) -> Self {
-        Compiler {
+        Self {
             encoding,
             instructions: Default::default(),
             free_space_start: 0,
@@ -288,6 +289,7 @@ where
         addr_range
     }
 
+    #[must_use]
     pub fn compile(mut self, ast: Ast<P>) -> Program<P> {
         let mut enable_nth_of_type = false;
         self.instructions = iter::repeat_with(|| None)
@@ -370,7 +372,7 @@ mod tests {
         vec![
             (selector.to_string(), test_cases.to_owned()),
             (
-                format!(":not({})", selector),
+                format!(":not({selector})"),
                 test_cases
                     .iter()
                     .map(|(input, should_match)| (*input, !should_match))
@@ -403,7 +405,7 @@ mod tests {
         encoding: &'static Encoding,
         action: impl Fn(&str, &T, &SelectorState, LocalName, AttributeMatcher),
     ) {
-        for (input, matching_data) in test_cases.iter() {
+        for (input, matching_data) in test_cases {
             with_start_tag(input, encoding, |local_name, attr_matcher| {
                 let counter = Default::default();
                 let state = SelectorState {
@@ -481,7 +483,7 @@ mod tests {
         encoding: &'static Encoding,
         test_cases: &[(&str, bool)],
     ) {
-        for (selector, test_cases) in with_negated(selector, test_cases).iter() {
+        for (selector, test_cases) in &with_negated(selector, test_cases) {
             assert_attr_expr_matches(selector, encoding, test_cases);
         }
     }
@@ -599,7 +601,7 @@ mod tests {
 
     #[test]
     fn compiled_non_attr_expression() {
-        for encoding in ASCII_COMPATIBLE_ENCODINGS.iter() {
+        for encoding in &ASCII_COMPATIBLE_ENCODINGS {
             assert_non_attr_expr_matches_and_negation_reverses_match(
                 "*",
                 encoding,
@@ -665,7 +667,7 @@ mod tests {
 
     #[test]
     fn compiled_attr_expression() {
-        for encoding in ASCII_COMPATIBLE_ENCODINGS.iter() {
+        for encoding in &ASCII_COMPATIBLE_ENCODINGS {
             assert_attr_expr_matches_and_negation_reverses_match(
                 "#foo⾕",
                 encoding,
@@ -884,7 +886,7 @@ mod tests {
 
     #[test]
     fn generic_expressions() {
-        for encoding in ASCII_COMPATIBLE_ENCODINGS.iter() {
+        for encoding in &ASCII_COMPATIBLE_ENCODINGS {
             assert_generic_expr_matches(
                 r#"div#foo1.c1.c2[foo3੦][foo2$="bar"]"#,
                 encoding,
@@ -914,7 +916,7 @@ mod tests {
             );
 
             assert_generic_expr_matches(
-                r#"some-thing[lang|=en]"#,
+                r"some-thing[lang|=en]",
                 encoding,
                 &[
                     ("<some-thing lang='en-GB'", true),
diff --git a/src/selectors_vm/error.rs b/src/selectors_vm/error.rs
index ae00eb12..bd6dd1dc 100644
--- a/src/selectors_vm/error.rs
+++ b/src/selectors_vm/error.rs
@@ -67,18 +67,18 @@ impl From<SelectorParseError<'_>> for SelectorError {
         #[deny(clippy::wildcard_enum_match_arm)]
         match err.kind {
             ParseErrorKind::Basic(err) => match err {
-                BasicParseErrorKind::UnexpectedToken(_) => SelectorError::UnexpectedToken,
-                BasicParseErrorKind::EndOfInput => SelectorError::UnexpectedEnd,
+                BasicParseErrorKind::UnexpectedToken(_) => Self::UnexpectedToken,
+                BasicParseErrorKind::EndOfInput => Self::UnexpectedEnd,
                 BasicParseErrorKind::AtRuleBodyInvalid
                 | BasicParseErrorKind::AtRuleInvalid(_)
-                | BasicParseErrorKind::QualifiedRuleInvalid => SelectorError::UnsupportedSyntax,
+                | BasicParseErrorKind::QualifiedRuleInvalid => Self::UnsupportedSyntax,
             },
             ParseErrorKind::Custom(err) => match err {
                 SelectorParseErrorKind::NoQualifiedNameInAttributeSelector(_) => {
-                    SelectorError::MissingAttributeName
+                    Self::MissingAttributeName
                 }
-                SelectorParseErrorKind::EmptySelector => SelectorError::EmptySelector,
-                SelectorParseErrorKind::DanglingCombinator => SelectorError::DanglingCombinator,
+                SelectorParseErrorKind::EmptySelector => Self::EmptySelector,
+                SelectorParseErrorKind::DanglingCombinator => Self::DanglingCombinator,
                 SelectorParseErrorKind::UnsupportedPseudoClassOrElement(_)
                 | SelectorParseErrorKind::PseudoElementInComplexSelector
                 | SelectorParseErrorKind::NonPseudoElementAfterSlotted
@@ -92,23 +92,23 @@ impl From<SelectorParseError<'_>> for SelectorError {
                 // NOTE: according to the parser code this error occures only during
                 // the parsing of the :slotted() pseudo-class.
                 | SelectorParseErrorKind::NonSimpleSelectorInNegation => {
-                    SelectorError::UnsupportedPseudoClassOrElement
+                    Self::UnsupportedPseudoClassOrElement
                 }
                 // NOTE: this is currently the only case in the parser code
                 // that triggers this error.
-                SelectorParseErrorKind::UnexpectedIdent(_) => SelectorError::NestedNegation,
-                SelectorParseErrorKind::ExpectedNamespace(_) => SelectorError::NamespacedSelector,
+                SelectorParseErrorKind::UnexpectedIdent(_) => Self::NestedNegation,
+                SelectorParseErrorKind::ExpectedNamespace(_) => Self::NamespacedSelector,
                 SelectorParseErrorKind::ExplicitNamespaceUnexpectedToken(_) => {
-                    SelectorError::UnexpectedToken
+                    Self::UnexpectedToken
                 }
                 SelectorParseErrorKind::UnexpectedTokenInAttributeSelector(_)
                 | SelectorParseErrorKind::ExpectedBarInAttr(_)
                 | SelectorParseErrorKind::BadValueInAttr(_)
                 | SelectorParseErrorKind::InvalidQualNameInAttr(_) => {
-                    SelectorError::UnexpectedTokenInAttribute
+                    Self::UnexpectedTokenInAttribute
                 }
-                SelectorParseErrorKind::ClassNeedsIdent(_) => SelectorError::InvalidClassName,
-                SelectorParseErrorKind::EmptyNegation => SelectorError::EmptyNegation,
+                SelectorParseErrorKind::ClassNeedsIdent(_) => Self::InvalidClassName,
+                SelectorParseErrorKind::EmptyNegation => Self::EmptyNegation,
                 SelectorParseErrorKind::InvalidState => panic!("invalid state"),
             },
         }
diff --git a/src/selectors_vm/mod.rs b/src/selectors_vm/mod.rs
index b9c7c148..1d573203 100644
--- a/src/selectors_vm/mod.rs
+++ b/src/selectors_vm/mod.rs
@@ -1,3 +1,5 @@
+#![allow(clippy::needless_pass_by_value)]
+
 mod ast;
 mod attribute_matcher;
 mod compiler;
@@ -95,7 +97,7 @@ impl<'i, E: ElementData> ExecutionCtx<'i, E> {
         branch: &ExecutionBranch<E::MatchPayload>,
         match_handler: &mut dyn FnMut(MatchInfo<E::MatchPayload>),
     ) {
-        for &payload in branch.matched_payload.iter() {
+        for &payload in &branch.matched_payload {
             let element_payload = self.stack_item.element_data.matched_payload_mut();
 
             if !element_payload.contains(&payload) {
@@ -149,6 +151,7 @@ where
     E: ElementData + Send,
 {
     #[inline]
+    #[must_use]
     pub fn new(
         ast: Ast<E::MatchPayload>,
         encoding: &'static Encoding,
@@ -158,7 +161,7 @@ where
         let program = Compiler::new(encoding).compile(ast);
         let enable_nth_of_type = program.enable_nth_of_type;
 
-        SelectorMatchingVm {
+        Self {
             program,
             enable_esi_tags,
             stack: Stack::new(memory_limiter, enable_nth_of_type),
@@ -395,7 +398,7 @@ where
                         recovery_point: addr - start + 1,
                     });
                 }
-                _ => (),
+                TryExecResult::Fail => (),
             }
         }
 
@@ -580,6 +583,35 @@ mod tests {
         }
     }
 
+    pub struct TestTransformController<T: FnMut(&mut Token)>(T);
+
+    impl<T: FnMut(&mut Token)> TransformController for TestTransformController<T> {
+        fn initial_capture_flags(&self) -> TokenCaptureFlags {
+            TokenCaptureFlags::all()
+        }
+
+        fn handle_start_tag(&mut self, _: LocalName, _: Namespace) -> StartTagHandlingResult<Self> {
+            Ok(TokenCaptureFlags::NEXT_START_TAG)
+        }
+
+        fn handle_end_tag(&mut self, _: LocalName) -> TokenCaptureFlags {
+            TokenCaptureFlags::all()
+        }
+
+        fn handle_end(&mut self, _: &mut DocumentEnd) -> Result<(), RewritingError> {
+            Ok(())
+        }
+
+        fn handle_token(&mut self, token: &mut Token) -> Result<(), RewritingError> {
+            (self.0)(token);
+            Ok(())
+        }
+
+        fn should_emit_content(&self) -> bool {
+            true
+        }
+    }
+
     pub fn test_with_token(
         html: &str,
         encoding: &'static Encoding,
@@ -598,39 +630,6 @@ mod tests {
             return;
         }
 
-        pub struct TestTransformController<T: FnMut(&mut Token)>(T);
-
-        impl<T: FnMut(&mut Token)> TransformController for TestTransformController<T> {
-            fn initial_capture_flags(&self) -> TokenCaptureFlags {
-                TokenCaptureFlags::all()
-            }
-
-            fn handle_start_tag(
-                &mut self,
-                _: LocalName,
-                _: Namespace,
-            ) -> StartTagHandlingResult<Self> {
-                Ok(TokenCaptureFlags::NEXT_START_TAG)
-            }
-
-            fn handle_end_tag(&mut self, _: LocalName) -> TokenCaptureFlags {
-                TokenCaptureFlags::all()
-            }
-
-            fn handle_end(&mut self, _: &mut DocumentEnd) -> Result<(), RewritingError> {
-                Ok(())
-            }
-
-            fn handle_token(&mut self, token: &mut Token) -> Result<(), RewritingError> {
-                (self.0)(token);
-                Ok(())
-            }
-
-            fn should_emit_content(&self) -> bool {
-                true
-            }
-        }
-
         let mut transform_stream = TransformStream::new(TransformStreamSettings {
             transform_controller: TestTransformController(test_fn),
             output_sink: |_: &[u8]| {},
diff --git a/src/selectors_vm/parser.rs b/src/selectors_vm/parser.rs
index ed8b0cbd..ae8248df 100644
--- a/src/selectors_vm/parser.rs
+++ b/src/selectors_vm/parser.rs
@@ -33,7 +33,7 @@ pub enum PseudoElementStub {}
 
 impl ToCss for PseudoElementStub {
     fn to_css<W: fmt::Write>(&self, _dest: &mut W) -> fmt::Result {
-        match *self {}
+        unimplemented!()
     }
 }
 
@@ -48,21 +48,21 @@ impl NonTSPseudoClass for NonTSPseudoClassStub {
     type Impl = SelectorImplDescriptor;
 
     fn is_active_or_hover(&self) -> bool {
-        match *self {}
+        unimplemented!()
     }
 
     fn is_user_action_state(&self) -> bool {
-        match *self {}
+        unimplemented!()
     }
 
     fn has_zero_specificity(&self) -> bool {
-        match *self {}
+        unimplemented!()
     }
 }
 
 impl ToCss for NonTSPseudoClassStub {
     fn to_css<W: fmt::Write>(&self, _dest: &mut W) -> fmt::Result {
-        match *self {}
+        unimplemented!()
     }
 }
 
@@ -134,7 +134,7 @@ impl SelectorsParser {
     fn validate(
         selector_list: SelectorList<SelectorImplDescriptor>,
     ) -> Result<SelectorList<SelectorImplDescriptor>, SelectorError> {
-        for selector in selector_list.0.iter() {
+        for selector in &selector_list.0 {
             for component in selector.iter_raw_match_order() {
                 Self::validate_component(component)?;
             }
@@ -214,6 +214,6 @@ impl FromStr for Selector {
 
     #[inline]
     fn from_str(selector: &str) -> Result<Self, Self::Err> {
-        Ok(Selector(SelectorsParser::parse(selector)?))
+        Ok(Self(SelectorsParser::parse(selector)?))
     }
 }
diff --git a/src/selectors_vm/stack.rs b/src/selectors_vm/stack.rs
index 7f8c4055..6d03be93 100644
--- a/src/selectors_vm/stack.rs
+++ b/src/selectors_vm/stack.rs
@@ -56,7 +56,8 @@ pub struct ChildCounter {
 
 impl ChildCounter {
     #[inline]
-    pub fn new_and_inc() -> Self {
+    #[must_use]
+    pub const fn new_and_inc() -> Self {
         Self { cumulative: 1 }
     }
 
@@ -66,7 +67,8 @@ impl ChildCounter {
     }
 
     #[inline]
-    pub fn is_nth(&self, nth: NthChild) -> bool {
+    #[must_use]
+    pub const fn is_nth(&self, nth: NthChild) -> bool {
         nth.has_index(self.cumulative)
     }
 }
@@ -176,6 +178,7 @@ pub struct StackItem<'i, E: ElementData> {
 
 impl<'i, E: ElementData> StackItem<'i, E> {
     #[inline]
+    #[must_use]
     pub fn new(local_name: LocalName<'i>) -> Self {
         StackItem {
             local_name,
@@ -212,7 +215,7 @@ pub struct Stack<E: ElementData> {
 
 impl<E: ElementData> Stack<E> {
     pub fn new(memory_limiter: SharedMemoryLimiter, enable_nth_of_type: bool) -> Self {
-        Stack {
+        Self {
             root_child_counter: Default::default(),
             typed_child_counters: if enable_nth_of_type {
                 Some(Default::default())
@@ -236,6 +239,7 @@ impl<E: ElementData> Stack<E> {
         }
     }
 
+    #[must_use]
     pub fn build_state<'a, 'i>(&'a self, name: &LocalName<'i>) -> SelectorState<'i>
     where
         'a: 'i, // 'a outlives 'i, required to downcast 'a lifetimes into 'i
@@ -254,6 +258,7 @@ impl<E: ElementData> Stack<E> {
     }
 
     #[inline]
+    #[must_use]
     pub fn get_stack_directive(
         item: &StackItem<E>,
         ns: Namespace,
@@ -277,16 +282,17 @@ impl<E: ElementData> Stack<E> {
             .rposition(|item| item.local_name == local_name);
         if let Some(index) = pop_to_index {
             if let Some(c) = self.typed_child_counters.as_mut() {
-                c.pop_to(index)
+                c.pop_to(index);
             }
             self.items
                 .drain(index..)
                 .map(|i| i.element_data)
-                .for_each(popped_element_data_handler)
+                .for_each(popped_element_data_handler);
         }
     }
 
     #[inline]
+    #[must_use]
     pub fn items(&self) -> &[StackItem<E>] {
         &self.items
     }
diff --git a/src/transform_stream/dispatcher.rs b/src/transform_stream/dispatcher.rs
index 1ff99e83..c27e7cca 100644
--- a/src/transform_stream/dispatcher.rs
+++ b/src/transform_stream/dispatcher.rs
@@ -9,7 +9,7 @@ use crate::rewritable_units::{
 };
 use crate::rewriter::RewritingError;
 
-use TagTokenOutline::*;
+use TagTokenOutline::{EndTag, StartTag};
 
 pub struct AuxStartTagInfo<'i> {
     pub input: &'i Bytes<'i>,
@@ -81,7 +81,7 @@ where
     pub fn new(transform_controller: C, output_sink: O, encoding: SharedEncoding) -> Self {
         let initial_capture_flags = transform_controller.initial_capture_flags();
 
-        Dispatcher {
+        Self {
             transform_controller,
             output_sink,
             remaining_content_start: 0,
@@ -168,7 +168,7 @@ where
     }
 
     #[inline]
-    fn get_next_parser_directive(&self) -> ParserDirective {
+    const fn get_next_parser_directive(&self) -> ParserDirective {
         if self.token_capturer.has_captures() {
             ParserDirective::Lex
         } else {
diff --git a/src/transform_stream/mod.rs b/src/transform_stream/mod.rs
index c59750c3..1ba68309 100644
--- a/src/transform_stream/mod.rs
+++ b/src/transform_stream/mod.rs
@@ -61,7 +61,7 @@ where
 
         let parser = Parser::new(dispatcher, initial_parser_directive, settings.strict);
 
-        TransformStream {
+        Self {
             parser,
             buffer,
             has_buffered_data: false,