diff --git a/crates/generate/src/node_types.rs b/crates/generate/src/node_types.rs
index 07be52c6..6ebb5e6d 100644
--- a/crates/generate/src/node_types.rs
+++ b/crates/generate/src/node_types.rs
@@ -102,7 +102,7 @@ impl ChildQuantity {
         }
     }
 
-    fn append(&mut self, other: Self) {
+    const fn append(&mut self, other: Self) {
         if other.exists {
             if self.exists || other.multiple {
                 self.multiple = true;
@@ -114,7 +114,7 @@ impl ChildQuantity {
         }
     }
 
-    fn union(&mut self, other: Self) -> bool {
+    const fn union(&mut self, other: Self) -> bool {
         let mut result = false;
         if !self.exists && other.exists {
             result = true;
diff --git a/crates/highlight/src/highlight.rs b/crates/highlight/src/highlight.rs
index 1f76bfc3..ee617124 100644
--- a/crates/highlight/src/highlight.rs
+++ b/crates/highlight/src/highlight.rs
@@ -275,7 +275,7 @@ impl Highlighter {
         }
     }
 
-    pub fn parser(&mut self) -> &mut Parser {
+    pub const fn parser(&mut self) -> &mut Parser {
         &mut self.parser
     }
 
@@ -1098,7 +1098,7 @@ impl HtmlRenderer {
         result
     }
 
-    pub fn set_carriage_return_highlight(&mut self, highlight: Option<Highlight>) {
+    pub const fn set_carriage_return_highlight(&mut self, highlight: Option<Highlight>) {
         self.carriage_return_highlight = highlight;
     }
 
diff --git a/crates/loader/src/loader.rs b/crates/loader/src/loader.rs
index 1c93a54d..b6086f5c 100644
--- a/crates/loader/src/loader.rs
+++ b/crates/loader/src/loader.rs
@@ -1455,15 +1455,15 @@ impl Loader {
         }
     }
 
-    pub fn debug_build(&mut self, flag: bool) {
+    pub const fn debug_build(&mut self, flag: bool) {
         self.debug_build = flag;
     }
 
-    pub fn sanitize_build(&mut self, flag: bool) {
+    pub const fn sanitize_build(&mut self, flag: bool) {
         self.sanitize_build = flag;
     }
 
-    pub fn force_rebuild(&mut self, rebuild: bool) {
+    pub const fn force_rebuild(&mut self, rebuild: bool) {
         self.force_rebuild = rebuild;
     }
 
diff --git a/crates/tags/src/tags.rs b/crates/tags/src/tags.rs
index b139ce00..8334fac2 100644
--- a/crates/tags/src/tags.rs
+++ b/crates/tags/src/tags.rs
@@ -274,7 +274,7 @@ impl TagsContext {
         }
     }
 
-    pub fn parser(&mut self) -> &mut Parser {
+    pub const fn parser(&mut self) -> &mut Parser {
         &mut self.parser
     }