diff --git a/build.gradle b/build.gradle
index b957115..3af61d0 100644
--- a/build.gradle
+++ b/build.gradle
@@ -2,8 +2,8 @@ apply plugin: 'com.android.library'
 apply plugin: 'me.tatarka.retrolambda'
 
 android {
-    compileSdkVersion 25
-    buildToolsVersion '25.0.3'
+    compileSdkVersion compileSdk
+    buildToolsVersion buildTools
 
     compileOptions {
         sourceCompatibility JavaVersion.VERSION_1_8
@@ -16,7 +16,7 @@ android {
 }
 
 dependencies {
-    provided 'com.android.support:support-annotations:25.4.0'
-    provided 'io.reactivex:rxandroid:1.2.1'
-    provided 'io.reactivex:rxjava:1.3.2'
+    provided "com.android.support:support-annotations:$supportLibraryVersion"
+    provided "io.reactivex:rxandroid:$rxAndroidVersion"
+    provided "io.reactivex:rxjava:$rxJavaVersion"
 }