Can you link some documentation explaining what it does?

I suspect this is related:

Error:Execution failed for task ':app:processDebugManifest'.
Manifest merger failed : Attribute meta-data#android.support.VERSION@value value=(26.1.0) from [com.android.support:design:26.1.0] AndroidManifest.xml:28:13-35
is also present at [com.android.support:exifinterface:26.0.2] AndroidManifest.xml:25:13-35 value=(26.0.2).
Suggestion: add 'tools:replace="android:value"' to element at AndroidManifest.xml:26:9-28:38 to override.

(Edited from my previous solution)
To fix it, I have to put in my own build.gradle:

configurations.all {
    resolutionStrategy {
        force "com.android.support:exifinterface:$supportLibVersion"
    }
}

I'm no gradle expert but I hope that helps understand what's going on!

@lisawray exactly
@ArthurHub transitive libraries will be available in modules, which depend on your library. This can cause issues when people use other library versions than you. @lisawray gave you a good example just above. If you set transitive to false, such conflicts will no longer occur even without that workaround.
More info on that here: official gradle docs

added in 2.5.1, hope it solves the merge issue, thx @j-garin