diff --git a/src/main.ts b/src/main.ts
index d294bc1..838eced 100644
--- a/src/main.ts
+++ b/src/main.ts
@@ -1,7 +1,9 @@
-import { Plugin, Editor } from "obsidian";
+import { Plugin, TFile } from "obsidian";
 import { syncCheckboxes } from "./checkboxUtils";
 
 export default class CheckboxSyncPlugin extends Plugin {
+  private isProcessing = false;
+
   async onload() {
     this.registerEvent(
       this.app.workspace.on("editor-change", (editor) => {
@@ -14,5 +16,31 @@ export default class CheckboxSyncPlugin extends Plugin {
         }
       })
     );
+    this.registerEvent(
+      this.app.vault.on("modify", async (file) => {
+        if (this.isProcessing || !(file instanceof TFile) || file.extension !== "md") return;
+
+        this.isProcessing = true;
+        try {
+          await this.syncFileCheckboxes(file);
+        } finally {
+          this.isProcessing = false;
+        }
+      })
+    );
   }
-}
+
+  async syncFileCheckboxes(file: TFile) {
+    const text = await this.app.vault.read(file);
+    const updates = syncCheckboxes(text);
+    if (updates.length === 0) return;
+
+    const lines = text.split("\n");
+    updates.forEach(({ line, ch, value }) => {
+      lines[line] = lines[line].substring(0, ch) + value + lines[line].substring(ch + 1);
+    });
+
+    const updatedText = lines.join("\n");
+    await this.app.vault.modify(file, updatedText);
+  }
+}
\ No newline at end of file