diff --git a/.changeset/heavy-dolls-search.md b/.changeset/heavy-dolls-search.md
new file mode 100644
index 0000000..c751ab3
--- /dev/null
+++ b/.changeset/heavy-dolls-search.md
@@ -0,0 +1,5 @@
+---
+'pliny': patch
+---
+
+fix toc slugs are tracked across documents
diff --git a/packages/pliny/src/mdx-plugins/remark-toc-headings.ts b/packages/pliny/src/mdx-plugins/remark-toc-headings.ts
index 7076e47..543cb2c 100644
--- a/packages/pliny/src/mdx-plugins/remark-toc-headings.ts
+++ b/packages/pliny/src/mdx-plugins/remark-toc-headings.ts
@@ -6,8 +6,6 @@ import GithubSlugger from 'github-slugger'
 import { toString } from 'mdast-util-to-string'
 import { remark } from 'remark'
 
-const slugger = new GithubSlugger()
-
 export type TocItem = {
   value: string
   url: string
@@ -20,6 +18,7 @@ export type Toc = TocItem[]
  * Extracts TOC headings from markdown file and adds it to the file's data object.
  */
 export function remarkTocHeadings() {
+  const slugger = new GithubSlugger()
   return (tree: Parent, file: VFile) => {
     const toc: Toc = []
     visit(tree, 'heading', (node: Heading) => {