Plugin-heavy Capacitor apps built on the default template fail Google Play's 2027 DEX rule

Play scores every uploaded bundle on three percentages: obfuscation, optimisation and shrinking ^[3]. For bundles built with AGP 8.10 or later, it reads them from an r8.json file inside the bundle, and any shrinker counts ^[8]. According to Capawesome, a Capacitor app on the default template scores close to zero on all three ^[3]. Capawesome's own app sat 24 percentage points under the 25% floor ^[22].

The rule does not reach every Capacitor app. The threshold is 10 MB of DEX code for apps and 50 MB for games ^[1][7]. According to Capawesome, the Capacitor, Firebase and Play Services dependencies together are enough to push an app with many plugins past 10 MB ^[23]. A lean app on the default template will also score near zero, but it falls outside the rule ^[3][1]. The post does not give a DEX size for a bare template build, so a team with only a few plugins has to measure its own bundle against the threshold.

The startup crash happens where two defaults meet. R8 has run in full mode by default since AGP 8.0 ^[11]. Capacitor's consumer rules keep every class annotated with @CapacitorPlugin and its public @PluginMethod methods. They also keep its @PermissionCallback and @ActivityCallback methods, even private ones ^[12]. They do not keep the annotation types themselves ^[12]. In Capawesome's logcat, the first launch of the minified build died in the CapacitorPlugins thread with a NullPointerException ^[20]. The fix is `-keep @interface com.getcapacitor.** { *; }` in proguard-rules.pro. The post marks that line as required in full mode and links it to ionic-team/capacitor issue #8589 ^[14].

We think the rest of Capacitor's consumer rules are careful work. Capacitor looks up permission and activity callbacks by method name at runtime, and its rules keep those methods, so permission requests and activity results survive R8 without any rule in the app ^[21]. AGP's defaults keep the @JavascriptInterface methods that Capacitor's MessageHandler uses to receive calls from JavaScript ^[16]. Firebase and Play Billing ship consumer rules of their own ^[17].

Capawesome's figures come from one production app on Capacitor 8.5.0 and AGP 8.13.2 ^[5]. Its steps assume Capacitor 8 and AGP 8.x ^[19]. For the result to carry over to another app, that app's plugins have to need nothing beyond what the post lists. The annotation rule applies to every Capacitor app, according to the post ^[14]. The plugin-specific lines do not carry over. Capawesome's -dontwarn entries cover optional database backends that its plugins probe for at runtime. For other apps, the post points to the missing_rules.txt file to find the equivalents ^[18]. In our view, any team near the 10 MB line should turn R8 on now and refuse to ship until a minified build launches cleanly. The Play threshold takes effect in February 2027 ^[1].