diff --git a/data/radar/2024-03-01/demo-4.md b/data/radar/2024-03-01/demo-4.md
index 0850078..d565cba 100644
--- a/data/radar/2024-03-01/demo-4.md
+++ b/data/radar/2024-03-01/demo-4.md
@@ -5,4 +5,4 @@ quadrant: languages-and-frameworks
 tags: [new]
 ---
 
-This is a new demo entry. Items can [link](/methods-and-patterns/demo-1/) to other items.
+This is a new demo entry. Items can [link](/methods-and-patterns/demo-1.html) to other items and replaces the old links with a html extension to the new link structure, whereas a new [link](/methods-and-patterns/demo-1/) should be untouched.
diff --git a/package.json b/package.json
index 82c6a4e..ce3abe0 100644
--- a/package.json
+++ b/package.json
@@ -1,6 +1,6 @@
 {
   "name": "aoe_technology_radar",
-  "version": "4.0.0-alpha.9",
+  "version": "4.0.0-alpha.10",
   "private": true,
   "bin": {
     "techradar": "./bin/techradar.js"
diff --git a/scripts/buildData.ts b/scripts/buildData.ts
index a684ee2..65c7799 100644
--- a/scripts/buildData.ts
+++ b/scripts/buildData.ts
@@ -37,6 +37,9 @@ function dataPath(...paths: string[]): string {
 }
 
 function convertToHtml(markdown: string): string {
+  // replace deprecated internal links with .html extension
+  markdown = markdown.replace(/(]\(\/[^)]+)\.html/g, "$1/");
+
   if (nextConfig.basePath) {
     markdown = markdown.replace(/]\(\//g, `](${nextConfig.basePath}/`);
   }