diff --git a/app/build.gradle b/app/build.gradle
index 79fbe88..b05acf9 100644
--- a/app/build.gradle
+++ b/app/build.gradle
@@ -37,6 +37,14 @@ android {
     kotlinOptions {
         jvmTarget = "1.8"
     }
+    configurations.all {
+        resolutionStrategy.eachDependency { DependencyResolveDetails details ->
+            if (details.requested.group == 'org.jetbrains.kotlinx:kotlinx-coroutines') {
+                details.useVersion "$coroutines_version"
+                details.because 'Different lib versions from different sources.'
+            }
+        }
+    }
 }
 
 dependencies {
@@ -55,7 +63,9 @@ dependencies {
     testImplementation 'junit:junit:4.12'
     testImplementation "android.arch.core:core-testing:1.1.1"
     testImplementation "android.arch.persistence.room:testing:1.1.1"
-    testImplementation 'org.jetbrains.kotlinx:kotlinx-coroutines-test:1.3.0-RC2'
+    testImplementation "org.jetbrains.kotlinx:kotlinx-coroutines-test:$coroutines_version"
+    testImplementation "org.jetbrains.kotlinx:kotlinx-coroutines-core:$coroutines_version"
+    testImplementation "org.jetbrains.kotlinx:kotlinx-coroutines-android:$coroutines_version"
     androidTestImplementation 'androidx.test:runner:1.2.0'
     androidTestImplementation 'androidx.test.espresso:espresso-core:3.2.0'
 }
diff --git a/build.gradle b/build.gradle
index 9a30a35..575374f 100644
--- a/build.gradle
+++ b/build.gradle
@@ -1,5 +1,9 @@
 // Top-level build file where you can add configuration options common to all sub-projects/modules.
 
+ext {
+    coroutines_version = "1.3.0-RC2"
+}
+
 buildscript {
     ext.kotlin_version = '1.3.41'