diff --git a/.github/workflows/CI.yaml b/.github/workflows/CI.yaml
index 32adb21bf..38f756b0f 100644
--- a/.github/workflows/CI.yaml
+++ b/.github/workflows/CI.yaml
@@ -23,7 +23,7 @@ jobs:
       - name: Install host dependencies
         run: |
           sudo apt-get update
-          sudo apt-get install flatpak flatpak-builder mutter
+          sudo apt-get install flatpak mutter
 
       # Restore caches
       - name: Restore Flatpak dependencies
diff --git a/.vscode/settings.json b/.vscode/settings.json
index 00f2c3e71..cad2dd06c 100644
--- a/.vscode/settings.json
+++ b/.vscode/settings.json
@@ -29,8 +29,5 @@
   "[json]": {
     "editor.defaultFormatter": "esbenp.prettier-vscode"
   },
-  "vala.languageServerPath": "${workspaceFolder}/.flatpak/vala-language-server.sh",
-  "mesonbuild.configureOnOpen": false,
-  "mesonbuild.buildFolder": "_build",
-  "mesonbuild.mesonPath": "${workspaceFolder}/.flatpak/meson.sh"
+  "vala.languageServerPath": "${workspaceFolder}/.flatpak/vala-language-server.sh"
 }
diff --git a/Makefile b/Makefile
index 10562ed5e..b7cf1d482 100644
--- a/Makefile
+++ b/Makefile
@@ -14,11 +14,10 @@ setup:
 	@echo "✅ You can use "make build" to build Workbench"
 
 stable:
-	flatpak-builder --delete-build-dirs --disable-updates --build-only --ccache --force-clean flatpak build-aux/re.sonny.Workbench.json
+	flatpak run org.flatpak.Builder --delete-build-dirs --disable-updates --build-only --ccache --force-clean flatpak build-aux/re.sonny.Workbench.json
 
 devel:
-	flatpak-builder --version
-	flatpak-builder --delete-build-dirs --disable-updates --build-only --ccache --force-clean flatpak build-aux/re.sonny.Workbench.Devel.json
+	flatpak run org.flatpak.Builder --delete-build-dirs --disable-updates --build-only --ccache --force-clean flatpak build-aux/re.sonny.Workbench.Devel.json
 
 build: devel
 
@@ -72,12 +71,12 @@ sandbox: setup
 	flatpak run --command="bash" re.sonny.Workbench.Devel
 
 flatpak:
-	 flatpak run org.flatpak.Builder --ccache --force-clean flatpak build-aux/re.sonny.Workbench.Devel.json
+	flatpak run org.flatpak.Builder --ccache --force-clean flatpak build-aux/re.sonny.Workbench.Devel.json
 # This is what Flathub does - consider moving to lint
 	flatpak run --env=G_DEBUG=fatal-criticals --command=appstream-util org.flatpak.Builder validate flatpak/files/share/appdata/re.sonny.Workbench.Devel.appdata.xml
 	flatpak run --command="desktop-file-validate" --filesystem=host:ro org.freedesktop.Sdk//23.08 flatpak/files/share/applications/re.sonny.Workbench.Devel.desktop
 # appstreamcli validate --override=release-time-missing=info /path/to/your/app.metainfo.xml
-	 flatpak run org.flatpak.Builder --run flatpak build-aux/re.sonny.Workbench.Devel.json bash
+	flatpak run org.flatpak.Builder --run flatpak build-aux/re.sonny.Workbench.Devel.json bash
 
 # Sync with .gitignore
 clean:
diff --git a/build-aux/re.sonny.Workbench.Devel.json b/build-aux/re.sonny.Workbench.Devel.json
index da9c18381..b867a95d7 100644
--- a/build-aux/re.sonny.Workbench.Devel.json
+++ b/build-aux/re.sonny.Workbench.Devel.json
@@ -1,4 +1,5 @@
 {
+  "$schema": "https://raw.githubusercontent.com/flatpak/flatpak-builder/main/data/flatpak-manifest.schema.json",
   "id": "re.sonny.Workbench.Devel",
   "runtime": "org.gnome.Sdk",
   "runtime-version": "master",
diff --git a/build-aux/re.sonny.Workbench.json b/build-aux/re.sonny.Workbench.json
index fea9e01d2..4f6e3ab48 100644
--- a/build-aux/re.sonny.Workbench.json
+++ b/build-aux/re.sonny.Workbench.json
@@ -1,4 +1,5 @@
 {
+  "$schema": "https://raw.githubusercontent.com/flatpak/flatpak-builder/main/data/flatpak-manifest.schema.json",
   "id": "re.sonny.Workbench",
   "runtime": "org.gnome.Sdk",
   "runtime-version": "46",
diff --git a/src/Extensions/Extensions.blp b/src/Extensions/Extensions.blp
index 6017b5ac0..266b05e7f 100644
--- a/src/Extensions/Extensions.blp
+++ b/src/Extensions/Extensions.blp
@@ -53,17 +53,14 @@ Adw.Dialog dialog {
 
             $Extension extension_rust {
               title: _("Rust");
-              command: "flatpak install flathub org.freedesktop.Sdk.Extension.rust-stable//24.08 org.freedesktop.Sdk.Extension.llvm18//24.08";
             }
 
             $Extension extension_vala {
               title: _("Vala");
-              command: "flatpak install flathub org.freedesktop.Sdk.Extension.vala//24.08";
             }
 
             $Extension extension_typescript {
               title: _("TypeScript");
-              command: "flatpak install flathub org.freedesktop.Sdk.Extension.node20//24.08 org.freedesktop.Sdk.Extension.typescript//24.08";
             }
           }
 
diff --git a/src/Extensions/Extensions.js b/src/Extensions/Extensions.js
index 06279bfd9..570bcab24 100644
--- a/src/Extensions/Extensions.js
+++ b/src/Extensions/Extensions.js
@@ -6,6 +6,7 @@ import Interface from "./Extensions.blp" with { type: "uri" };
 import illustration from "./extensions.svg";
 
 import "./Extension.js";
+import { getFlatpakInfo } from "../util.js";
 
 export const action_extensions = new Gio.SimpleAction({
   name: "extensions",
@@ -26,8 +27,13 @@ export function Extensions({ window }) {
   picture_illustration.set_resource(illustration);
 
   extension_rust.enabled = isRustEnabled();
+  extension_rust.command = `flatpak install flathub org.freedesktop.Sdk.Extension.rust-stable//${freedesktop_version} org.freedesktop.Sdk.Extension.${llvm}//${freedesktop_version}`;
+
   extension_vala.enabled = isValaEnabled();
+  extension_vala.command = `flatpak install flathub org.freedesktop.Sdk.Extension.vala//${freedesktop_version}`;
+
   extension_typescript.enabled = isTypeScriptEnabled();
+  extension_typescript.command = `flatpak install flathub org.freedesktop.Sdk.Extension.${node}//${freedesktop_version} org.freedesktop.Sdk.Extension.typescript//${freedesktop_version}`;
 
   for (const extension of [
     extension_rust,
@@ -47,25 +53,30 @@ export function Extensions({ window }) {
   window.add_action(action_extensions);
 }
 
-let rust_enabled;
+let rust_enabled = false;
 export function isRustEnabled() {
   rust_enabled ??=
     Gio.File.new_for_path("/usr/lib/sdk/rust-stable").query_exists(null) &&
-    Gio.File.new_for_path("/usr/lib/sdk/llvm18").query_exists(null);
+    Gio.File.new_for_path(`/usr/lib/sdk/${llvm}`).query_exists(null);
   return rust_enabled;
 }
 
-let vala_enabled;
+let vala_enabled = false;
 export function isValaEnabled() {
   vala_enabled ??=
     Gio.File.new_for_path("/usr/lib/sdk/vala").query_exists(null);
   return vala_enabled;
 }
 
-let typescript_enabled;
+let typescript_enabled = false;
 export function isTypeScriptEnabled() {
   typescript_enabled ??=
     Gio.File.new_for_path("/usr/lib/sdk/typescript").query_exists(null) &&
-    Gio.File.new_for_path("/usr/lib/sdk/node20").query_exists(null);
+    Gio.File.new_for_path(`/usr/lib/sdk/${node}`).query_exists(null);
   return typescript_enabled;
 }
+
+const llvm = "llvm18";
+const node = "node20";
+const runtime = getFlatpakInfo().get_string("Application", "runtime");
+const freedesktop_version = runtime.endsWith("master") ? "24.08beta" : "23.08";
diff --git a/src/util.js b/src/util.js
index 028cfbdc5..958307cb2 100644
--- a/src/util.js
+++ b/src/util.js
@@ -25,17 +25,19 @@ export function ensureDir(file) {
   }
 }
 
+let flatpak_info;
 export function getFlatpakInfo() {
-  const keyFile = new GLib.KeyFile();
+  if (flatpak_info) return flatpak_info;
+  flatpak_info = new GLib.KeyFile();
   try {
-    keyFile.load_from_file("/.flatpak-info", GLib.KeyFileFlags.NONE);
+    flatpak_info.load_from_file("/.flatpak-info", GLib.KeyFileFlags.NONE);
   } catch (err) {
     if (!err.matches(GLib.FileError, GLib.FileError.NOENT)) {
       console.error(err);
     }
     return null;
   }
-  return keyFile;
+  return flatpak_info;
 }
 
 export { getLanguage };