diff --git a/Nuvolari/README.md b/Nuvolari/README.md
index c41b03c..fb99baf 100644
--- a/Nuvolari/README.md
+++ b/Nuvolari/README.md
@@ -30,6 +30,11 @@ Start with [docs/architecture.md](docs/architecture.md), then
 | Android SDK | platform 36, build-tools 36.0.0, platform-tools |
 | JDK | 21 |
 | Python | 3.12+ (3.14 works; rasterio ships wheels for it) |
+| Android NDK | 28.2.13676358 — pinned by `maplibre_gl`, not by this project |
+
+A full toolchain plus a warm Gradle cache needs roughly **14 GB** of disk: Flutter
+3 GB, Android SDK 2.5 GB (2 GB of which is the NDK the map plugin pins), the Gradle
+cache 5 GB, and build output around 2 GB. `flutter clean` reclaims the last of those.
 
 ## Configuration
 
diff --git a/Nuvolari/app/android/app/build.gradle.kts b/Nuvolari/app/android/app/build.gradle.kts
index 2a1dffa..2a17a0d 100644
--- a/Nuvolari/app/android/app/build.gradle.kts
+++ b/Nuvolari/app/android/app/build.gradle.kts
@@ -11,6 +11,11 @@ android {
     // Flutter cannot silently move targetSdk. Google Play requires API 36 as of
     // 2026-08-31, and that requirement is a release blocker, not a default.
     compileSdk = 36
+
+    // Required even though this project has no native sources of its own:
+    // maplibre_gl pins ndkVersion 28.2.13676358 in its own build file, and
+    // AGP needs every module to agree on one NDK. Costs ~2 GB of SDK; do not
+    // drop it while the map plugin is a dependency.
     ndkVersion = flutter.ndkVersion
 
     compileOptions {