diff --git a/.github/workflows/build.yml b/.github/workflows/build.yml
index 9ecf6ad..1d41ebe 100644
--- a/.github/workflows/build.yml
+++ b/.github/workflows/build.yml
@@ -27,8 +27,8 @@ on:
 
 env:
   # Use SHA or tag instead of the branch for caching purposes.
-  MONO_TAG: mono-6.12.0.122
-  PYTHON_VERSION: 3.8
+  MONO_TAG: mono-6.12.0.144
+  PYTHON_VERSION: 3.9
   # Should match the version that Mono supports.
   EMSDK_VERSION: 1.39.9
   ANDROID_CMAKE_VERSION: 3.10.2.4988404
@@ -36,6 +36,7 @@ env:
   # platform/android/java/app/config.gradle
   ANDROID_PLATFORM: android-29
   ANDROID_API: 18
+  ANDROID_NDK_VERSION: 21.4.7075529
   # platform/iphone/detect.py
   IOS_VERSION_MIN: 10.0
 
@@ -428,10 +429,10 @@ jobs:
         run: |
           sudo snap install androidsdk
           androidsdk "platforms;${ANDROID_PLATFORM}"
-          androidsdk "ndk-bundle"
+          androidsdk "ndk;${ANDROID_NDK_VERSION}"
           androidsdk "cmake;${ANDROID_CMAKE_VERSION}"
           echo "ANDROID_SDK_ROOT=$HOME/snap/androidsdk/current/" >> $GITHUB_ENV
-          echo "ANDROID_NDK_ROOT=$ANDROID_SDK_ROOT/ndk-bundle" >> $GITHUB_ENV
+          echo "ANDROID_NDK_ROOT=$ANDROID_SDK_ROOT/ndk/$ANDROID_NDK_VERSION" >> $GITHUB_ENV
       - name: Cache Mono Sources
         id: cache_mono_sources
         uses: actions/cache@v2.1.5
@@ -557,11 +558,10 @@ jobs:
         run: |
           sudo apt-get -y install snapd
           sudo snap install androidsdk
-          androidsdk "platforms;${ANDROID_PLATFORM}"
-          androidsdk "ndk-bundle"
+          androidsdk "ndk;${ANDROID_NDK_VERSION}"
           androidsdk "cmake;${ANDROID_CMAKE_VERSION}"
           echo "ANDROID_SDK_ROOT=$HOME/snap/androidsdk/current/" >> $GITHUB_ENV
-          echo "ANDROID_NDK_ROOT=$ANDROID_SDK_ROOT/ndk-bundle" >> $GITHUB_ENV
+          echo "ANDROID_NDK_ROOT=$ANDROID_SDK_ROOT/ndk/$ANDROID_NDK_VERSION" >> $GITHUB_ENV
       - name: Cache Mono Sources
         id: cache_mono_sources
         uses: actions/cache@v2.1.5
diff --git a/README.md b/README.md
index 38e10e8..647d24b 100644
--- a/README.md
+++ b/README.md
@@ -9,7 +9,7 @@ This repository contains scripts for building the Mono runtime to use with Godot
 The scripts are tested against specific versions of the toolchains used by Godot.
 While they may work with other versions, you might have issues applying patches or compiling, so we recommend using the versions below.
 
-- Mono: 6.12.0.122.
+- Mono: 6.12.0.144.
 - Emscripten: 1.39.9.
 - Android: API level 29.