diff --git a/docusaurus.config.js b/docusaurus.config.js
index 3487b3e..5c1e4c6 100644
--- a/docusaurus.config.js
+++ b/docusaurus.config.js
@@ -58,6 +58,15 @@ const subjects = [
   new Docs("cpp", "C++"),
 ];
 
+const fallbackMapping = [
+  { new: "algorithms", old: ["ib002"] },
+  { new: "functional", old: ["ib015"] },
+  { new: "automata", old: ["ib110"] },
+  { new: "foundations", old: ["ib111"] },
+  { new: "c", old: ["pb071"] },
+  { new: "cpp", old: ["pb161"] },
+];
+
 /** @type {import('@docusaurus/types').Config} */
 const config = {
   title: "mf",
@@ -115,6 +124,22 @@ const config = {
       },
     ],
     "docusaurus-plugin-sass",
+    [
+      "@docusaurus/plugin-client-redirects",
+      {
+        createRedirects(existingPath) {
+          for (let mapping of fallbackMapping) {
+            if (existingPath.includes(`/${mapping.new}/`)) {
+              return mapping.old.map((old) =>
+                existingPath.replace(`/${mapping.new}/`, `/${old}/`)
+              );
+            }
+          }
+
+          return undefined; // no redirect created
+        },
+      },
+    ],
   ],
 
   stylesheets: [
diff --git a/package.json b/package.json
index 8a5af4e..1ad8ba4 100644
--- a/package.json
+++ b/package.json
@@ -15,6 +15,7 @@
   },
   "dependencies": {
     "@docusaurus/core": "^3.0.0",
+    "@docusaurus/plugin-client-redirects": "^3.0.0",
     "@docusaurus/preset-classic": "^3.0.0",
     "@docusaurus/theme-mermaid": "^3.0.0",
     "@mdx-js/react": "^3.0.0",
diff --git a/yarn.lock b/yarn.lock
index 55ae7fb..1cd4fa1 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -1355,6 +1355,21 @@
     react-helmet-async "*"
     react-loadable "npm:@docusaurus/react-loadable@5.5.2"
 
+"@docusaurus/plugin-client-redirects@^3.0.0":
+  version "3.0.0"
+  resolved "https://registry.yarnpkg.com/@docusaurus/plugin-client-redirects/-/plugin-client-redirects-3.0.0.tgz#983880c467228ed8b1aba5f20ce564696e25f363"
+  integrity sha512-JcZLod4lgPdbv/OpCbNwTc57u54d01dcWiDy/sBaxls/4HkDGdj6838oBPzbBdnCWrmasBIRz3JYLk+1GU0IOQ==
+  dependencies:
+    "@docusaurus/core" "3.0.0"
+    "@docusaurus/logger" "3.0.0"
+    "@docusaurus/utils" "3.0.0"
+    "@docusaurus/utils-common" "3.0.0"
+    "@docusaurus/utils-validation" "3.0.0"
+    eta "^2.2.0"
+    fs-extra "^11.1.1"
+    lodash "^4.17.21"
+    tslib "^2.6.0"
+
 "@docusaurus/plugin-content-blog@3.0.0":
   version "3.0.0"
   resolved "https://registry.yarnpkg.com/@docusaurus/plugin-content-blog/-/plugin-content-blog-3.0.0.tgz#5f3ede003b2b7103043918fbe3f436c116839ca8"