ERROR: Missing classes detected while running R8. Please add the missing classes or apply additional keep rules that are generated in .../build/app/outputs/mapping/.../.txt.

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ERROR: Missing classes detected while running R8. Please add the missing classes or apply additional keep rules that are generated in .../build/app/outputs/mapping/.../.txt.

Khalid Aziz 25

Missing classes detected while running R8. Please add the missing classes or apply additional keep rules that are generated

Adnan Ayoub 0 Reputation points

2025-05-20T10:48:27.8333333+00:00

Hello, @Michele Ariis we are using both chat and calling features in our application. Could you please guide us on how to implement or manage them effectively?

We are facing the same issue "Missing classes detected while running R8"
Michele Ariis 1,960 Reputation points MVP

2025-05-20T11:36:08.6+00:00

Hello, to use ACS Calling and Chat SDKs together on Android without the R8 “Missing classes” error, use Calling SDK ≥ 2.11.0, exclude trouter-client-android only from Chat, and add minimal ProGuard rules (-keep for com.azure.android.communication.** and com.microsoft.trouterclient.**, plus a few -dontwarn). Don’t rely on -ignorewarnings or failOnMissingClasses=false ,they don’t work well with AGP 8+. If R8 still breaks, check missing_rules.txt, copy the suggested rules, and rebuild. For a simpler setup, use the ACS UI Libraries, which bundle everything and avoid R8 issues by default.

Adnan Ayoub 0

This is Proguard rules, with these rules apk size becomes 160 Mb

-keep class com.microsoft.azure.** { *; }
-keep class com.azure.** { *; }
-keep class com.azure.android.** { *; }
-keep class com.azure.core.** { *; }

-keep @interface com.microsoft.azure.** { *; }
-keep @interface com.azure.** { *; }
-keep class com.azure.core.http.** { *; }
-keep class com.azure.core.client.** { *; }
-keep class com.azure.core.util.logging.** { *; }
-keep class *.R$ { *; }

# Azure SDK (keep only what you use)
-keep class com.azure.storage.blob.** { *; }
-keep class com.azure.core.http.** { *; }
-keep class com.skype.** { *; }
-keep class com.microsoft.trouterclient.** { *; }

# Suppress warnings for desktop Java classes
-dontwarn java.awt.**
-dontwarn java.beans.**
-dontwarn javax.activation.*
-dontwarn aQute.bnd.annotation.Resolution
-dontwarn aQute.bnd.annotation.spi.ServiceProvider

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Adnan Ayoub 0 Reputation points

2025-05-20T10:48:27.8333333+00:00

Hello, @Michele Ariis we are using both chat and calling features in our application. Could you please guide us on how to implement or manage them effectively?

We are facing the same issue "Missing classes detected while running R8"
Michele Ariis 1,960 Reputation points MVP

2025-05-20T11:36:08.6+00:00

Hello, to use ACS Calling and Chat SDKs together on Android without the R8 “Missing classes” error, use Calling SDK ≥ 2.11.0, exclude trouter-client-android only from Chat, and add minimal ProGuard rules (-keep for com.azure.android.communication.** and com.microsoft.trouterclient.**, plus a few -dontwarn). Don’t rely on -ignorewarnings or failOnMissingClasses=false ,they don’t work well with AGP 8+. If R8 still breaks, check missing_rules.txt, copy the suggested rules, and rebuild. For a simpler setup, use the ACS UI Libraries, which bundle everything and avoid R8 issues by default.
Adnan Ayoub 0 Reputation points

2025-05-21T04:14:43.1866667+00:00

This is Proguard rules, with these rules apk size becomes 160 Mb

-keep class com.microsoft.azure.** { *; } -keep class com.azure.** { *; } -keep class com.azure.android.** { *; } -keep class com.azure.core.** { *; } -keep @interface com.microsoft.azure.** { *; } -keep @interface com.azure.** { *; } -keep class com.azure.core.http.** { *; } -keep class com.azure.core.client.** { *; } -keep class com.azure.core.util.logging.** { *; } -keep class *.R$ { *; } # Azure SDK (keep only what you use) -keep class com.azure.storage.blob.** { *; } -keep class com.azure.core.http.** { *; } -keep class com.skype.** { *; } -keep class com.microsoft.trouterclient.** { *; } # Suppress warnings for desktop Java classes -dontwarn java.awt.** -dontwarn java.beans.** -dontwarn javax.activation.* -dontwarn aQute.bnd.annotation.Resolution -dontwarn aQute.bnd.annotation.spi.ServiceProvider

Answer 1

Michele Ariis 1,960 MVP

-Open the R8 report.

You can find it at: app/build/outputs/mapping/<flavorRelease>/missing_rules.txt.

Inside, you’ll see a detailed list of missing classes or suggested -keep / -dontwarn rules.

Fix the issue using one (ideally both) of these methods:

Add the missing libraries in your build.gradle file (e.g., Conscrypt, SLF4J, etc.).

Copy the recommended rules from the report into your proguard-rules.pro (or consumer-rules.pro if you're publishing a library).

Then, rebuild the project using ./gradlew clean assembleRelease or your Azure DevOps pipeline.

If new missing classes are detected, the report will be regenerated. Repeat this process until the build passes.

Avoid shortcuts.

Options like -ignorewarnings or android.r8.failOnMissingClasses=false only work with AGP ≤ 7.x and reduce security.

Khalid Aziz 25 Reputation points

2025-05-14T13:07:07.65+00:00

Following this Method by using dontwarn, the app size becomes 180 mb
Michele Ariis 1,960 Reputation points MVP

2025-05-14T13:18:49.5066667+00:00

Using a blanket -dontwarn (or -ignorewarnings) tells R8 to assume missing classes are fine and to keep any code that might reference them. Since R8 can't safely remove code when references are unresolved, it keeps far more than needed, which is why your APK or AAB has grown to around 180 MB. To fix this, you should stop using broad -dontwarn rules and instead add the missing dependencies or apply specific keep rules suggested in missing_rules.txt. You can also use the --whyareyoukeeping option to understand why certain classes are retained and adjust your rules accordingly. The process is simple: review missing classes, add libraries or keep rules, rebuild, and repeat until clean. Once done, remove broad -dontwarn entries. This approach reduces package size, avoids hidden runtime crashes, and ensures compatibility with AGP 8+. Blanket -dontwarn should only be used as a last resort in legacy builds; targeted fixes are the right solution for modern projects.

Khalid Aziz 25

This is my progaurd file:

-keep class com.microsoft.azure.** { *; }
-keep class com.azure.** { *; }
-keep class com.azure.android.** { *; }
-keep class com.azure.core.** { *; }

-keep @interface com.microsoft.azure.** { *; }
-keep @interface com.azure.** { *; }
-keep class com.azure.core.http.** { *; }
-keep class com.azure.core.client.** { *; }
-keep class com.azure.core.util.logging.** { *; }
-keep class **.R$* { *; }

-dontwarn com.squareup.okhttp.CipherSuite
-dontwarn com.squareup.okhttp.ConnectionSpec
-dontwarn com.squareup.okhttp.TlsVersion
-dontwarn org.bouncycastle.jsse.BCSSLSocket
-dontwarn org.bouncycastle.jsse.provider.BouncyCastleJsseProvider
-dontwarn org.conscrypt.Conscrypt$Version
-dontwarn org.conscrypt.Conscrypt
-dontwarn org.conscrypt.ConscryptHostnameVerifier
-dontwarn org.joda.convert.FromString
-dontwarn org.joda.convert.ToString
-dontwarn org.openjsse.javax.net.ssl.SSLParameters
-dontwarn org.openjsse.javax.net.ssl.SSLSocket
-dontwarn org.openjsse.net.ssl.OpenJSSE
-dontwarn com.google.devtools.build.android.desugar.runtime.ThrowableExtension
-dontwarn java.awt.**
-dontwarn java.beans.**
-dontwarn com.sun.activation.**
-dontwarn org.bouncycastle.**
-dontwarn org.slf4j.**


Removing any one of the dontwarn shows me error:

Missing classes detected while running R8. Please add the missing classes or apply additional keep rules that are generated in /Users/khalid/AndroidStudioProjects/Timbers/app/build/outputs/mapping/release/missing_rules.txt.

Task :app:minifyReleaseWithR8
AGPBI: {"kind":"warning","text":"Unexpected reference to missing service class: META-INF/services/org.codehaus.stax2.validation.XMLValidationSchemaFactory.dtd.","sources":[{"file":"/Users/khalid/AndroidStudioProjects/Timbers/app/build/intermediates/merged_java_res/release/mergeReleaseJavaResource/base.jar"}],"tool":"R8"}
AGPBI: {"kind":"warning","text":"Unexpected reference to missing service class: META-INF/services/org.codehaus.stax2.validation.XMLValidationSchemaFactory.relaxng.","sources":[{"file":"/Users/khalid/AndroidStudioProjects/Timbers/app/build/intermediates/merged_java_res/release/mergeReleaseJavaResource/base.jar"}],"tool":"R8"}
AGPBI: {"kind":"warning","text":"Unexpected reference to missing service class: META-INF/services/org.codehaus.stax2.validation.XMLValidationSchemaFactory.w3c.","sources":[{"file":"/Users/khalid/AndroidStudioProjects/Timbers/app/build/intermediates/merged_java_res/release/mergeReleaseJavaResource/base.jar"}],"tool":"R8"}
AGPBI: {"kind":"warning","text":"Unexpected reference to missing service class: META-INF/services/reactor.blockhound.integration.BlockHoundIntegration.","sources":[{"file":"/Users/khalid/AndroidStudioProjects/Timbers/app/build/intermediates/merged_java_res/release/mergeReleaseJavaResource/base.jar"}],"tool":"R8"}
> Task :app:minifyReleaseWithR8 FAILED
AGPBI: {"kind":"error","text":"Missing classes detected while running R8. Please add the missing classes or apply additional keep rules that are generated in /Users/khalid/AndroidStudioProjects/Timbers/app/build/outputs/mapping/release/missing_rules.txt.","sources":[{}]}
AGPBI: {"kind":"error","text":"Missing class aQute.bnd.annotation.spi.ServiceProvider (referenced from: com.ctc.wstx.dtd.DTDSchemaFactory and 5 other contexts)\nMissing class org.bouncycastle.jsse.BCSSLParameters (referenced from: void okhttp3.internal.platform.BouncyCastlePlatform.configureTlsExtensions(javax.net.ssl.SSLSocket, java.lang.String, java.util.List) and 1 other context)\nMissing class org.bouncycastle.jsse.BCSSLSocket (referenced from: void okhttp3.internal.platform.BouncyCastlePlatform.configureTlsExtensions(javax.net.ssl.SSLSocket, java.lang.String, java.util.List) and 5 other contexts)\nMissing class org.bouncycastle.jsse.provider.BouncyCastleJsseProvider (referenced from: void okhttp3.internal.platform.BouncyCastlePlatform.<init>())\nMissing class org.conscrypt.Conscrypt$Version (referenced from: boolean okhttp3.internal.platform.ConscryptPlatform$Companion.atLeastVersion(int, int, int))\nMissing class org.conscrypt.Conscrypt (referenced from: boolean okhttp3.internal.platform.ConscryptPlatform$Companion.atLeastVersion(int, int, int) and 4 other contexts)\nMissing class org.conscrypt.ConscryptHostnameVerifier (referenced from: okhttp3.internal.platform.ConscryptPlatform$DisabledHostnameVerifier)\nMissing class org.openjsse.javax.net.ssl.SSLParameters (referenced from: void okhttp3.internal.platform.OpenJSSEPlatform.configureTlsExtensions(javax.net.ssl.SSLSocket, java.lang.String, java.util.List))\nMissing class org.openjsse.javax.net.ssl.SSLSocket (referenced from: void okhttp3.internal.platform.OpenJSSEPlatform.configureTlsExtensions(javax.net.ssl.SSLSocket, java.lang.String, java.util.List) and 1 other context)\nMissing class org.openjsse.net.ssl.OpenJSSE (referenced from: void okhttp3.internal.platform.OpenJSSEPlatform.<init>())\nMissing class org.slf4j.impl.StaticLoggerBinder (referenced from: void org.slf4j.LoggerFactory.bind() and 3 other contexts)\nMissing class reactor.blockhound.integration.BlockHoundIntegration (referenced from: reactor.core.scheduler.ReactorBlockHoundIntegration)","sources":[{}],"tool":"R8"}
Missing classes detected while running R8. Please add the missing classes or apply additional keep rules that are generated in /Users/khalid/AndroidStudioProjects/Timbers/app/build/outputs/mapping/release/missing_rules.txt.
Missing class aQute.bnd.annotation.spi.ServiceProvider (referenced from: com.ctc.wstx.dtd.DTDSchemaFactory and 5 other contexts)
Missing class org.bouncycastle.jsse.BCSSLParameters (referenced from: void okhttp3.internal.platform.BouncyCastlePlatform.configureTlsExtensions(javax.net.ssl.SSLSocket, java.lang.String, java.util.List) and 1 other context)
Missing class org.bouncycastle.jsse.BCSSLSocket (referenced from: void okhttp3.internal.platform.BouncyCastlePlatform.configureTlsExtensions(javax.net.ssl.SSLSocket, java.lang.String, java.util.List) and 5 other contexts)
Missing class org.bouncycastle.jsse.provider.BouncyCastleJsseProvider (referenced from: void okhttp3.internal.platform.BouncyCastlePlatform.<init>())
Missing class org.conscrypt.Conscrypt$Version (referenced from: boolean okhttp3.internal.platform.ConscryptPlatform$Companion.atLeastVersion(int, int, int))
Missing class org.conscrypt.Conscrypt (referenced from: boolean okhttp3.internal.platform.ConscryptPlatform$Companion.atLeastVersion(int, int, int) and 4 other contexts)
Missing class org.conscrypt.ConscryptHostnameVerifier (referenced from: okhttp3.internal.platform.ConscryptPlatform$DisabledHostnameVerifier)
Missing class org.openjsse.javax.net.ssl.SSLParameters (referenced from: void okhttp3.internal.platform.OpenJSSEPlatform.configureTlsExtensions(javax.net.ssl.SSLSocket, java.lang.String, java.util.List))
Missing class org.openjsse.javax.net.ssl.SSLSocket (referenced from: void okhttp3.internal.platform.OpenJSSEPlatform.configureTlsExtensions(javax.net.ssl.SSLSocket, java.lang.String, java.util.List) and 1 other context)
Missing class org.openjsse.net.ssl.OpenJSSE (referenced from: void okhttp3.internal.platform.OpenJSSEPlatform.<init>())
Missing class org.slf4j.impl.StaticLoggerBinder (referenced from: void org.slf4j.LoggerFactory.bind() and 3 other contexts)
Missing class reactor.blockhound.integration.BlockHoundIntegration (referenced from: reactor.core.scheduler.ReactorBlockHoundIntegration)

this only happens when wetry to build signed apk.

Khalid Aziz 25 Reputation points

2025-05-14T13:56:51.5633333+00:00

Adding all the missing class as dontwarn and proceed , the app size becames 180mb
Michele Ariis 1,960 Reputation points MVP

2025-05-14T14:02:08.7833333+00:00

The problem is that your release build fails because R8 finds references to optional classes (Conscrypt, BouncyCastle, SLF4J, etc.) that you don't have in your project. These references come from the Azure SDK + OkHttp chain, but they are optional. With the new versions of Android Gradle Plugin (AGP 8+), these “missing-class” are no longer just warnings: they become blocking errors at build time (only in release, with minifyEnabled).

You can solve it in two ways:

Add the missing libraries as dependencies in build.gradle (e.g. Conscrypt, BouncyCastle, SLF4J) if you really need them.

Update OkHttp to version ≥ 4.11 and use exclude to remove the optional references you don't need. This is the best solution if you want a smaller APK and you don't use those features.

In any case, you may also want to clean up your ProGuard/R8 rules:

Remove generic wildcards like -keep class com.azure.** { *; }.

Keep only -keep for Azure APIs you use and reflection templates.

Use -dontwarn only for classes you know you don't really need.

Finally, do a check:

Run ./gradlew clean assembleRelease.

Check the missing_rules.txt file to see if there are any missing classes.

If so, either add them or leave them out.

Once everything is fine, the build will pass and your APK will be lean again.
Khalid Aziz 25 Reputation points

2025-05-14T17:47:58.2533333+00:00

Dear Azure Team,

Thank you for your suggestions. We have tried each and every solution you mentioned, including:

Adding missing libraries (such as Conscrypt, BouncyCastle, SLF4J) to the build.gradle as dependencies.

Updating OkHttp to version ≥ 4.11 and excluding the optional references we don’t need.

Cleaning up ProGuard/R8 rules, removing wildcard entries like -keep class com.azure.** { *; } and refining the rules for only the necessary Azure APIs and reflection templates. Additionally, we’ve used -dontwarnfor classes that are not needed.

Despite these efforts, we’re still facing the issue where the signed APK size remains large (around 171MB).

We have followed all the steps, including running ./gradlew clean assembleRelease and reviewing the missing classes, but it hasn’t resolved the problem. We are still unable to significantly reduce the APK size.

Could you please provide further guidance or any other recommendations that might help us reduce the app size while still using the Azure SDK and OkHttp?

Looking forward to your response.

Best regards, Khalid

Khalid Aziz 25

-keep class com.microsoft.azure.** { *; }
-keep class com.azure.** { *; }
-keep class com.azure.android.** { *; }
-keep class com.azure.core.** { *; }

-keep @interface com.microsoft.azure.** { *; }
-keep @interface com.azure.** { *; }
-keep class com.azure.core.http.** { *; }
-keep class com.azure.core.client.** { *; }
-keep class com.azure.core.util.logging.** { *; }
-keep class **.R$* { *; }

# Azure SDK (keep only what you use)
-keep class com.azure.storage.blob.** { *; }
-keep class com.azure.core.http.** { *; }
-keep class com.skype.** { *; }
-keep class com.microsoft.trouterclient.** { *; }
# Suppress warnings for desktop Java classes

-dontwarn java.awt.**
-dontwarn java.beans.**
-dontwarn javax.activation.**


These 3 dontwarn files are showing errors if removed, and when proceed like this app size is 180mb

Michele Ariis 1,960 Reputation points MVP

2025-05-15T07:34:34.7266667+00:00

Hi Khalid, your APK is still large because R8 can't shrink anything you're telling it to keep. Lines like -keep class com.azure.** { *; } prevent R8 from removing unused code. Since the Azure SDK itself is quite big, these wildcards stop any real optimization.

Here's what you should do:

First, remove those generic -keep rules. They're blocking most of R8's size savings. Don't worry if the build fails at first; that's expected. When it does, you'll see exactly which classes are actually required, usually a few model classes or things used via reflection.

Next, for each of those, add targeted keep rules. For example: -keep class com.azure.storage.blob.models.BlobItem { *; } This is much better than keeping entire packages.

Then, inspect your APK using the APK Analyzer in Android Studio. Look for large libraries or native files (like TLS providers or logging libs) that you might have added without needing them. Anything over 2 MB is worth checking.

If you're building a universal APK, consider splitting ABIs or moving to an AAB to avoid bundling all architectures. This alone can cut down 20–40 MB depending on the native libraries you're using.

Finally, use R8’s -whyareyoukeeping to understand why certain classes are not being removed. This will help you catch dependencies that are holding up your shrinkage.

In terms of size reduction, you can expect roughly:

-50 MB saved by removing those Azure wildcard rules

-20 MB by excluding optional jars you don’t really use

-20–40 MB by splitting ABIs or using an AAB

-Another 10 MB once R8 can fully optimize your code

Most apps that use Azure Blob and OkHttp end up in the 30–50 MB range after doing this cleanup.

A minimal ProGuard rules file should only keep the Azure clients you use, resource IDs, and maybe silence a few irrelevant desktop-related warnings. Everything else should be allowed to shrink.

If after doing this your APK is still larger than expected, share a screenshot of the APK Analyzer's top size offenders or show any strange R8 whyareyoukeeping results. That way we can narrow it down further.

Give it a try and let me know how much the size drops.
Khalid Aziz 25 Reputation points

2025-05-15T08:49:15.53+00:00

Hello sir,
Thank you very much for your time.

-keep class com.microsoft.azure.** { *; }

-keep class com.azure.** { *; }

-keep class com.azure.android.** { *; }

-keep class com.azure.core.** { *; }

-keep @interface com.microsoft.azure.** { *; }

-keep @interface com.azure.** { *; }

-keep class com.azure.core.http.** { *; }

-keep class com.azure.core.client.** { *; }

-keep class com.azure.core.util.logging.** { *; }

-keep class *.R$ { *; }

-dontwarn java.awt.**

-dontwarn java.beans.**

-dontwarn javax.activation.**

After applying these rules, my APK size is around 32 MB, but I noticed that libskypert.so alone is taking 15+ MB, which suggests that this native library is not being stripped or optimized during the build.

When I try removing the following -dontwarn lines:

-dontwarn java.awt.**

-dontwarn java.beans.**

-dontwarn javax.activation.**

I encounter missing class warnings and sometimes build-time errors, which means some part of the SDK or dependencies still reference these Java classes—even if they’re not used at runtime.
can you give me one working template for pro-gaurd
Khalid Aziz 25 Reputation points

2025-05-15T08:51:27.9166667+00:00
Michele Ariis 1,960 Reputation points MVP

2025-05-15T08:58:39+00:00
The big file is libskypert.so, a native library from Skype/Trouter. It's included once per ABI (x86, arm64, etc.). ProGuard can't shrink native code.

If you don’t need ACS (voice/video), exclude Trouter from dependencies:

implementation("com.azure:azure-communication-calling:...") { exclude group:"com.microsoft.trouterclient" }

If you need it, enable ABI splits (keep only arm64-v8a, armeabi-v7a) or use an AAB. This will cut 10-15 MB.

Clean up ProGuard rules. Remove wildcards like com.azure.** and keep only:

-keep class com.azure.storage.blob.BlobServiceClient { *; } -keep class **.R$* { *; } -dontwarn java.awt.** -dontwarn java.beans.** -dontwarn javax.activation.**

Check APK Analyzer to verify you only have the needed ABIs.
Khalid Aziz 25 Reputation points

2025-05-15T09:12:09.57+00:00

implementation("com.azure:azure-communication-calling:...") { exclude group:"com.microsoft.trouterclient" }

Hello sir,
This app involves only chat , no calling
Khalid Aziz 25 Reputation points

2025-05-15T10:14:34.5466667+00:00

The big file is libskypert.so
So if its used in calling only, i am not able to understand why its coming in my apk
Michele Ariis 1,960 Reputation points MVP

2025-05-15T10:44:48.0733333+00:00

libskypert.so comes from Trouter, used for chat WebSocket events, not just calls. It shows up even if you don’t use calling APIs.

./gradlew app:dependencies --configuration runtimeClasspath --dependency com.microsoft.trouterclient

You’ll see the chain: chat - common - trouterclient - libskypert.so

You can only remove it if you’re fine losing live message events (use polling or push instead).

Two options:

-No live events - use REST-only chat SDK (chat-rest)

-Need live events - keep SDK but reduce APK size with ABI splits or App Bundles
Ashok Gandhi Kotnana 10,115 Reputation points Microsoft External Staff Moderator

2025-05-16T10:52:10.72+00:00

Hi @Khalid Aziz,

If the response provided by @Michele Ariis, helpful

Please do not forget to "Accept the answer” wherever the information provided helps you, this can be beneficial to other community members.it would be greatly appreciated and helpful to others.
Adnan Ayoub 0 Reputation points

2025-05-27T04:10:56.6+00:00

This works only when we keep the R8 full mode false.

android.enableR8.fullMode=false

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ERROR: Missing classes detected while running R8. Please add the missing classes or apply additional keep rules that are generated in .../build/app/outputs/mapping/.../.txt.

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