diff --git a/app/build.gradle.kts b/app/build.gradle.kts
index 774640b9..663ee249 100644
--- a/app/build.gradle.kts
+++ b/app/build.gradle.kts
@@ -74,7 +74,7 @@ android {
             isMinifyEnabled = true
             isShrinkResources = true
             proguardFiles(
-                getDefaultProguardFile("proguard-android.txt"),
+                getDefaultProguardFile("proguard-android-optimize.txt"),
                 "proguard-rules.pro"
             )
             if (keystorePropertiesFile.exists() || hasSigningVars()) {
diff --git a/app/proguard-rules.pro b/app/proguard-rules.pro
index 50dfb901..59a78ffd 100644
--- a/app/proguard-rules.pro
+++ b/app/proguard-rules.pro
@@ -3,3 +3,6 @@
 -keep enum ezvcard.VCardVersion { *; }
 -dontwarn ezvcard.io.json.**
 -dontwarn freemarker.**
+-keep class ezvcard.parameter.** {
+    <init>(...);
+}