diff --git a/.scalafix.conf b/.scalafix.conf
new file mode 100644
index 0000000..bcee716
--- /dev/null
+++ b/.scalafix.conf
@@ -0,0 +1,5 @@
+rules = [
+  ExplicitResultTypes,
+  ProcedureSyntax,
+]
+ExplicitResultTypes.onlyImplicits = true
diff --git a/app/conf/Configuration.scala b/app/conf/Configuration.scala
index d0e43cc..05971f5 100644
--- a/app/conf/Configuration.scala
+++ b/app/conf/Configuration.scala
@@ -185,7 +185,7 @@ object Properties extends AutomaticResourceManagement {
 }
 
 trait AutomaticResourceManagement {
-  def withCloseable[T <: { def close() }](closeable: T) = new {
+  def withCloseable[T <: { def close(): Unit }](closeable: T) = new {
     def apply[S](body: T => S) = try {
       body(closeable)
     } finally {
diff --git a/app/controllers/DefaultsController.scala b/app/controllers/DefaultsController.scala
index dcb7e90..b03502d 100644
--- a/app/controllers/DefaultsController.scala
+++ b/app/controllers/DefaultsController.scala
@@ -8,9 +8,10 @@ import conf.ApplicationConfiguration
 import play.api.Mode.Dev
 import play.api.libs.ws.WSClient
 import story_packages.switchboard.SwitchManager
+import play.api.libs.json.OWrites
 
 object Defaults {
-  implicit val jsonFormat = Json.writes[Defaults]
+  implicit val jsonFormat: OWrites[Defaults] = Json.writes[Defaults]
 }
 
 case class Defaults(
diff --git a/app/story_packages/metrics/CloudWatch.scala b/app/story_packages/metrics/CloudWatch.scala
index 04f7dac..9d358b9 100644
--- a/app/story_packages/metrics/CloudWatch.scala
+++ b/app/story_packages/metrics/CloudWatch.scala
@@ -19,11 +19,11 @@ class CloudWatch(config: ApplicationConfiguration) extends Logging {
   }
 
   trait LoggingAsyncHandler extends AsyncHandler[PutMetricDataRequest, PutMetricDataResult] {
-    def onError(exception: Exception)
+    def onError(exception: Exception): Unit =
     {
       Logger.info(s"CloudWatch PutMetricDataRequest error: ${exception.getMessage}}")
     }
-    def onSuccess(request: PutMetricDataRequest, result: PutMetricDataResult )
+    def onSuccess(request: PutMetricDataRequest, result: PutMetricDataResult ): Unit =
     {
       Logger.info("CloudWatch PutMetricDataRequest - success")
     }
diff --git a/app/story_packages/metrics/metrics.scala b/app/story_packages/metrics/metrics.scala
index c7968a7..96fe76e 100644
--- a/app/story_packages/metrics/metrics.scala
+++ b/app/story_packages/metrics/metrics.scala
@@ -202,7 +202,7 @@ class CloudWatchApplicationMetrics(appName: String, stage: String, cloudWatch: C
       )
     )}
 
-  private def report() {
+  private def report(): Unit = {
     val allMetrics: List[FrontendMetric] = this.systemMetrics ::: this.applicationMetrics
     if (!isDev) {
       val stageDimension = new Dimension().withName("Stage").withValue(stage)
diff --git a/app/story_packages/model/StoryPackage.scala b/app/story_packages/model/StoryPackage.scala
index eb73818..0494da4 100644
--- a/app/story_packages/model/StoryPackage.scala
+++ b/app/story_packages/model/StoryPackage.scala
@@ -2,6 +2,7 @@ package story_packages.model
 
 import org.joda.time.{DateTime, DateTimeZone}
 import play.api.libs.json.Json
+import play.api.libs.json.OFormat
 
 case class StoryPackage(
   id: Option[String],
@@ -15,11 +16,11 @@ case class StoryPackage(
   deleted: Option[Boolean]
 ) {}
 object StoryPackage {
-  implicit val jsonFormat = Json.format[StoryPackage]
+  implicit val jsonFormat: OFormat[StoryPackage] = Json.format[StoryPackage]
 }
 
 object SortByLastModify {
-  implicit val sortByModifyDate = new Ordering[StoryPackage] {
+  implicit val sortByModifyDate: Ordering[StoryPackage] = new Ordering[StoryPackage] {
     def compare(a: StoryPackage, b: StoryPackage) = (a.lastModify, b.lastModify) match {
       case (None, None) => 0
       case (Some(_), None) => -1
@@ -29,7 +30,7 @@ object SortByLastModify {
   }
 }
 object SortByName {
-  implicit val sortByModifyDate = new Ordering[StoryPackage] {
+  implicit val sortByModifyDate: Ordering[StoryPackage] = new Ordering[StoryPackage] {
     def compare(a: StoryPackage, b: StoryPackage) = (a.name, b.name) match {
       case (None, None) => 0
       case (Some(_), None) => -1
diff --git a/app/story_packages/model/frontsapi.scala b/app/story_packages/model/frontsapi.scala
index 34aaf40..0cd7f0f 100644
--- a/app/story_packages/model/frontsapi.scala
+++ b/app/story_packages/model/frontsapi.scala
@@ -19,7 +19,7 @@ trait UpdateActionsTrait extends Logging {
   def frontsApi: FrontsApi
   def config: ApplicationConfiguration
 
-  implicit val updateListWrite = Json.writes[UpdateList]
+  implicit val updateListWrite: OWrites[UpdateList] = Json.writes[UpdateList]
 
   def insertIntoLive(update: UpdateList, identity: User, collectionJson: CollectionJson): CollectionJson = {
     val live = updateList(update, identity, collectionJson.live)
diff --git a/app/story_packages/services/S3.scala b/app/story_packages/services/S3.scala
index bb9a633..2c9dfea 100644
--- a/app/story_packages/services/S3.scala
+++ b/app/story_packages/services/S3.scala
@@ -62,11 +62,11 @@ trait S3 extends Logging {
     result => new DateTime(result.getObjectMetadata.getLastModified)
   }
 
-  def putPrivate(key: String, value: String, contentType: String) {
+  def putPrivate(key: String, value: String, contentType: String): Unit = {
     put(key: String, value: String, contentType: String, Private)
   }
 
-  private def put(key: String, value: String, contentType: String, accessControlList: CannedAccessControlList) {
+  private def put(key: String, value: String, contentType: String, accessControlList: CannedAccessControlList): Unit = {
     val metadata = new ObjectMetadata()
     metadata.setCacheControl("no-cache,no-store")
     metadata.setContentType(contentType)
diff --git a/app/story_packages/switchboard/Switchboard.scala b/app/story_packages/switchboard/Switchboard.scala
index 588f2f9..7e8e976 100644
--- a/app/story_packages/switchboard/Switchboard.scala
+++ b/app/story_packages/switchboard/Switchboard.scala
@@ -20,7 +20,7 @@ class Lifecycle(conf: SwitchboardConfiguration, scheduler: Scheduler) extends Lo
   Logger.info("Starting switchboard cache")
   scheduler.scheduleWithFixedDelay(initialDelay = 1.seconds, delay = 1.minute) { () => refreshSwitches() }
 
-  def refreshSwitches() {
+  def refreshSwitches(): Unit = {
     Logger.info("Refreshing switches from switchboard")
     client.getSwitches() foreach { response => SwitchManager.updateSwitches(response) }
   }
diff --git a/app/story_packages/updates/KinesisEventSender.scala b/app/story_packages/updates/KinesisEventSender.scala
index 00664e2..5d77197 100644
--- a/app/story_packages/updates/KinesisEventSender.scala
+++ b/app/story_packages/updates/KinesisEventSender.scala
@@ -121,7 +121,7 @@ class KinesisEventSender(config: ApplicationConfiguration) extends Logging {
         articles = createUpdatePayload(collectionJson)))
   }
 
-  def sendUpdate(streamName: String, collectionId: String, event: Event) {
+  def sendUpdate(streamName: String, collectionId: String, event: Event): Unit = {
     val request = new PutRecordsRequest().withStreamName(streamName)
     val bytes = ThriftSerializer.serializeToBytes(event, Some(GzipType), Some(128))
     if (bytes.length > config.updates.maxDataSize) {
diff --git a/app/story_packages/updates/Reindex.scala b/app/story_packages/updates/Reindex.scala
index 4356c6b..29d9916 100644
--- a/app/story_packages/updates/Reindex.scala
+++ b/app/story_packages/updates/Reindex.scala
@@ -11,6 +11,7 @@ import scala.concurrent.ExecutionContext.Implicits.global
 import scala.concurrent.Future
 import scala.concurrent.duration._
 import scala.util.control.NonFatal
+import play.api.libs.json.OFormat
 
 case class ReindexPage(
   totalCount: Int,
@@ -39,7 +40,7 @@ case class ReindexProgress(
   documentsExpected: Int
 )
 object ReindexProgress {
-  implicit val jsonFormat = Json.format[ReindexProgress]
+  implicit val jsonFormat: OFormat[ReindexProgress] = Json.format[ReindexProgress]
 }
 
 sealed trait ReindexStatus{val label: String}
diff --git a/app/story_packages/updates/UpdateMessage.scala b/app/story_packages/updates/UpdateMessage.scala
index af267bd..6f10c14 100644
--- a/app/story_packages/updates/UpdateMessage.scala
+++ b/app/story_packages/updates/UpdateMessage.scala
@@ -31,7 +31,7 @@ case class Remove(remove: UpdateList) extends UpdateMessage
 
 /* Macro - Watch out, this needs to be after the case classes */
 object UpdateMessage {
-  implicit val format = derived.flat.oformat[UpdateMessage]((__ \ "type").format[String])
+  implicit val format: OFormat[UpdateMessage] = derived.flat.oformat[UpdateMessage]((__ \ "type").format[String])
 }
 
 /* Kinesis messages */
diff --git a/project/plugins.sbt b/project/plugins.sbt
index 3b5e6c9..b9c585b 100644
--- a/project/plugins.sbt
+++ b/project/plugins.sbt
@@ -11,3 +11,5 @@ addSbtPlugin("com.typesafe.play" % "sbt-plugin" % "2.8.19")
 addSbtPlugin("com.eed3si9n" % "sbt-buildinfo" % "0.11.0")
 
 libraryDependencies += "org.vafer" % "jdeb" % "1.3" artifacts (Artifact("jdeb", "jar", "jar"))
+
+addSbtPlugin("ch.epfl.scala" % "sbt-scalafix" % "0.12.1")