diff --git a/lib/src/get_changed_ranges.c b/lib/src/get_changed_ranges.c
index 1715716a..5bd1d814 100644
--- a/lib/src/get_changed_ranges.c
+++ b/lib/src/get_changed_ranges.c
@@ -122,7 +122,7 @@ static bool iterator_done(Iterator *self) {
   return self->cursor.stack.size == 0;
 }
 
-Length iterator_start_position(Iterator *self) {
+static Length iterator_start_position(Iterator *self) {
   TreeCursorEntry entry = *array_back(&self->cursor.stack);
   if (self->in_padding) {
     return entry.position;
@@ -131,7 +131,7 @@ Length iterator_start_position(Iterator *self) {
   }
 }
 
-Length iterator_end_position(Iterator *self) {
+static Length iterator_end_position(Iterator *self) {
   TreeCursorEntry entry = *array_back(&self->cursor.stack);
   Length result = length_add(entry.position, ts_subtree_padding(*entry.subtree));
   if (self->in_padding) {
@@ -287,7 +287,7 @@ typedef enum {
   IteratorMatches,
 } IteratorComparison;
 
-IteratorComparison iterator_compare(const Iterator *old_iter, const Iterator *new_iter) {
+static IteratorComparison iterator_compare(const Iterator *old_iter, const Iterator *new_iter) {
   Subtree old_tree = NULL_SUBTREE;
   Subtree new_tree = NULL_SUBTREE;
   uint32_t old_start = 0;
diff --git a/lib/src/subtree.c b/lib/src/subtree.c
index 2e7d05a7..6a3a63df 100644
--- a/lib/src/subtree.c
+++ b/lib/src/subtree.c
@@ -18,8 +18,6 @@ typedef struct {
   Length new_end;
 } Edit;
 
-TSStateId TS_TREE_STATE_NONE = USHRT_MAX;
-
 #ifdef TREE_SITTER_TEST
 
 #define TS_MAX_INLINE_TREE_LENGTH 2
diff --git a/lib/src/subtree.h b/lib/src/subtree.h
index 611996d5..79ccd923 100644
--- a/lib/src/subtree.h
+++ b/lib/src/subtree.h
@@ -5,6 +5,7 @@
 extern "C" {
 #endif
 
+#include <limits.h>
 #include <stdbool.h>
 #include <stdio.h>
 #include "./length.h"
@@ -13,7 +14,7 @@ extern "C" {
 #include "tree_sitter/api.h"
 #include "tree_sitter/parser.h"
 
-extern TSStateId TS_TREE_STATE_NONE;
+static const TSStateId TS_TREE_STATE_NONE = USHRT_MAX;
 #define NULL_SUBTREE ((Subtree) {.ptr = NULL})
 
 typedef union Subtree Subtree;