diff --git a/briar-android/src/main/java/org/briarproject/briar/android/hotspot/ConditionManager.java b/briar-android/src/main/java/org/briarproject/briar/android/hotspot/ConditionManager.java
index 10c5f78e2..d8e217060 100644
--- a/briar-android/src/main/java/org/briarproject/briar/android/hotspot/ConditionManager.java
+++ b/briar-android/src/main/java/org/briarproject/briar/android/hotspot/ConditionManager.java
@@ -5,6 +5,7 @@ import android.content.Intent;
 import android.net.wifi.WifiManager;
 import android.provider.Settings;
 
+import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
 import org.briarproject.briar.R;
 
 import androidx.activity.result.ActivityResult;
@@ -29,6 +30,7 @@ import static org.briarproject.briar.android.util.UiUtils.getGoToSettingsListene
  * As soon as {@link #checkAndRequestConditions()} returns true,
  * all conditions are fulfilled.
  */
+@NotNullByDefault
 class ConditionManager {
 
 	private enum Permission {
diff --git a/briar-android/src/main/java/org/briarproject/briar/android/hotspot/HotspotState.java b/briar-android/src/main/java/org/briarproject/briar/android/hotspot/HotspotState.java
index 40e620fcc..0c304bc2a 100644
--- a/briar-android/src/main/java/org/briarproject/briar/android/hotspot/HotspotState.java
+++ b/briar-android/src/main/java/org/briarproject/briar/android/hotspot/HotspotState.java
@@ -2,8 +2,11 @@ package org.briarproject.briar.android.hotspot;
 
 import android.graphics.Bitmap;
 
+import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
+
 import androidx.annotation.Nullable;
 
+@NotNullByDefault
 abstract class HotspotState {
 
 	static class StartingHotspot extends HotspotState {
diff --git a/briar-android/src/main/java/org/briarproject/briar/android/hotspot/HotspotViewModel.java b/briar-android/src/main/java/org/briarproject/briar/android/hotspot/HotspotViewModel.java
index a897dac6b..33681a70e 100644
--- a/briar-android/src/main/java/org/briarproject/briar/android/hotspot/HotspotViewModel.java
+++ b/briar-android/src/main/java/org/briarproject/briar/android/hotspot/HotspotViewModel.java
@@ -31,6 +31,7 @@ import androidx.annotation.UiThread;
 import androidx.lifecycle.LiveData;
 import androidx.lifecycle.MutableLiveData;
 
+import static java.util.Objects.requireNonNull;
 import static java.util.logging.Logger.getLogger;
 
 @NotNullByDefault
@@ -136,7 +137,8 @@ class HotspotViewModel extends DbViewModel
 	@Override
 	@IoExecutor
 	public void onWebServerStarted(WebsiteConfig websiteConfig) {
-		state.postValue(new HotspotStarted(networkConfig, websiteConfig));
+		NetworkConfig nc = requireNonNull(networkConfig);
+		state.postValue(new HotspotStarted(nc, websiteConfig));
 		networkConfig = null;
 	}