diff --git a/build.sbt b/build.sbt
index a2374b181..8d569bac2 100644
--- a/build.sbt
+++ b/build.sbt
@@ -37,7 +37,8 @@ def compilerOptions(scalaVersion: String) = Seq(
   "-Ywarn-unused:params",              // Warn if a value parameter is unused.
   "-Ywarn-unused:patvars",             // Warn if a variable bound in a pattern is unused.
   "-Ywarn-unused:privates",            // Warn if a private member is unused.
-  "-Ywarn-value-discard"               // Warn when non-Unit expression results are unused.
+  "-Ywarn-value-discard",              // Warn when non-Unit expression results are unused.
+  "-Wnonunit-statement"                // Warn when non-unit statements are discarded.
 ) ++ (if (priorTo2_13(scalaVersion))
   Seq(
     "-Yno-adapted-args",
@@ -61,6 +62,7 @@ lazy val standardSettings = Seq(
   licenses += ("Apache-2.0", url("https://www.apache.org/licenses/LICENSE-2.0.html")),
   Test / fork := true,
   scalacOptions ++= compilerOptions(scalaVersion.value),
+  Test / scalacOptions -= "-Wnonunit-statement", // too noisy with Scalacheck
   javacOptions ++= Seq("-source", "8", "-target", "8"),
   // Additional meta-info required by maven central
   startYear := Some(2015),
diff --git a/cornichon-core/src/main/scala/com/github/agourlay/cornichon/dsl/BaseFeature.scala b/cornichon-core/src/main/scala/com/github/agourlay/cornichon/dsl/BaseFeature.scala
index 4744367bf..feacb02c1 100644
--- a/cornichon-core/src/main/scala/com/github/agourlay/cornichon/dsl/BaseFeature.scala
+++ b/cornichon-core/src/main/scala/com/github/agourlay/cornichon/dsl/BaseFeature.scala
@@ -61,7 +61,7 @@ object BaseFeature {
   def addShutdownHook(h: () => Future[_]): Unit =
     hooks.push(h)
 
-  def shutDownGlobalResources(): Future[Done] = {
+  def shutDownGlobalResources(): Future[Unit] = {
     import scala.concurrent.ExecutionContext.Implicits.global
     @tailrec
     def clearHooks(previous: Future[Any] = Future.successful[Any](())): Future[Any] =
@@ -69,10 +69,10 @@ object BaseFeature {
         case None => previous
         case Some(f) =>
           clearHooks {
-            previous.flatMap { _ => f().recover { case _ => Done } }
+            previous.flatMap { _ => f().recover { case _ => () } }
           }
       }
 
-    clearHooks().map(_ => Done)
+    clearHooks().map(_ => ())
   }
 }
diff --git a/cornichon-core/src/main/scala/com/github/agourlay/cornichon/dsl/BodyElementCollectorMacro.scala b/cornichon-core/src/main/scala/com/github/agourlay/cornichon/dsl/BodyElementCollectorMacro.scala
index 05197f5e2..af9c81105 100644
--- a/cornichon-core/src/main/scala/com/github/agourlay/cornichon/dsl/BodyElementCollectorMacro.scala
+++ b/cornichon-core/src/main/scala/com/github/agourlay/cornichon/dsl/BodyElementCollectorMacro.scala
@@ -80,7 +80,7 @@ class BodyElementCollectorMacro(context: blackbox.Context) {
     val validExpressions = Array.newBuilder[Tree]
     val errors = Array.newBuilder[(c.universe.Position, String)]
 
-    def evalTree(s: Tree) =
+    def evalTree(s: Tree): Unit =
       typeCheck(elementType, seq)(s) match {
         case Right(tree) => validExpressions += tree
         case Left(e)     => errors += e
diff --git a/cornichon-core/src/main/scala/com/github/agourlay/cornichon/dsl/CoreDsl.scala b/cornichon-core/src/main/scala/com/github/agourlay/cornichon/dsl/CoreDsl.scala
index c358a4beb..139486e2e 100644
--- a/cornichon-core/src/main/scala/com/github/agourlay/cornichon/dsl/CoreDsl.scala
+++ b/cornichon-core/src/main/scala/com/github/agourlay/cornichon/dsl/CoreDsl.scala
@@ -16,7 +16,7 @@ import scala.concurrent.duration.FiniteDuration
 
 trait CoreDsl {
 
-  def Feature(name: String) = FeatureBuilder(name)
+  def Feature(name: String): FeatureBuilder = FeatureBuilder(name)
 
   private[dsl] case class FeatureBuilder(name: String, ignored: Option[String] = None) {
     def ignoredBecause(reason: String): FeatureBuilder = copy(ignored = Some(reason))
@@ -26,14 +26,14 @@ trait CoreDsl {
   implicit final def featureBuilder(f: FeatureBuilder): BodyElementCollector[ScenarioDef, FeatureDef] =
     BodyElementCollector[ScenarioDef, FeatureDef](scenarios => FeatureDef(f.name, scenarios, f.ignored))
 
-  def Scenario(name: String) = ScenarioBuilder(name)
+  def Scenario(name: String): ScenarioBuilder = ScenarioBuilder(name)
 
   private[dsl] case class ScenarioBuilder(name: String, ignored: Option[String] = None, focus: Boolean = false) {
     def ignoredBecause(reason: String): ScenarioBuilder = copy(ignored = Some(reason))
     def ignoredIfDefined(reason: Option[String]): ScenarioBuilder = copy(ignored = reason)
     /** Focus on this scenario ignoring all other scenarios withing a `Feature` */
     def focused: ScenarioBuilder = copy(focus = true)
-    def pending = ScenarioDef(name, Nil, pending = true)
+    def pending: ScenarioDef = ScenarioDef(name, Nil, pending = true)
   }
 
   implicit final def scenarioBuilder(s: ScenarioBuilder): BodyElementCollector[Step, ScenarioDef] =
diff --git a/cornichon-core/src/main/scala/com/github/agourlay/cornichon/http/HttpService.scala b/cornichon-core/src/main/scala/com/github/agourlay/cornichon/http/HttpService.scala
index 86d2253f0..86a8e96d6 100644
--- a/cornichon-core/src/main/scala/com/github/agourlay/cornichon/http/HttpService.scala
+++ b/cornichon-core/src/main/scala/com/github/agourlay/cornichon/http/HttpService.scala
@@ -183,7 +183,7 @@ object HttpService {
 
   def decodeSessionHeaders(headers: String): Either[CornichonError, List[(String, String)]] =
     traverseIL(headers.split(interHeadersValueDelim).iterator) { header =>
-      val index = header.indexOf(headersKeyValueDelim)
+      val index = header.indexOf(headersKeyValueDelim.toInt)
       if (index == -1)
         Left(BadSessionHeadersEncoding(header))
       else
diff --git a/cornichon-core/src/main/scala/com/github/agourlay/cornichon/matchers/MatcherParser.scala b/cornichon-core/src/main/scala/com/github/agourlay/cornichon/matchers/MatcherParser.scala
index b726798bc..e0e54fbeb 100644
--- a/cornichon-core/src/main/scala/com/github/agourlay/cornichon/matchers/MatcherParser.scala
+++ b/cornichon-core/src/main/scala/com/github/agourlay/cornichon/matchers/MatcherParser.scala
@@ -12,7 +12,7 @@ class MatcherParser(val input: ParserInput) extends Parser {
     Ignore ~ zeroOrMore(MatcherRule).separatedBy(Ignore) ~ Ignore ~ EOI
   }
 
-  private def MatcherRule = rule("*" ~ MatcherTXT ~ "*" ~> MatcherKey)
+  private def MatcherRule = rule('*' ~ MatcherTXT ~ '*' ~> MatcherKey)
 
   private def MatcherTXT = rule(capture(oneOrMore(allowedCharsInMatcher)))
 
diff --git a/cornichon-core/src/test/scala/com/github/agourlay/cornichon/core/SessionProperties.scala b/cornichon-core/src/test/scala/com/github/agourlay/cornichon/core/SessionProperties.scala
index 2c78dcdbe..88d3433e6 100644
--- a/cornichon-core/src/test/scala/com/github/agourlay/cornichon/core/SessionProperties.scala
+++ b/cornichon-core/src/test/scala/com/github/agourlay/cornichon/core/SessionProperties.scala
@@ -92,8 +92,8 @@ object SessionProperties extends Properties("Session") {
     forAll(keyGen, valueGen, valueGen) { (key, firstValue, secondValue) =>
       val s = Session.newEmpty.addValueUnsafe(key, firstValue).addValueUnsafe(key, secondValue)
       val error = IndexNotFoundForKey(key, 3, Vector(firstValue, secondValue))
-      s.get(key, Some(3)) == Left(error)
-      error.renderedMessage == s"index '3' not found for key '$key' with values \n0 -> $firstValue\n1 -> $secondValue"
+      s.get(key, Some(3)) == Left(error) &&
+        error.renderedMessage == s"index '3' not found for key '$key' with values \n0 -> $firstValue\n1 -> $secondValue"
     }
 
   property("get proposes similar keys in Session in case of a missing key") =
diff --git a/cornichon-kafka/src/main/scala/com/github/agourlay/cornichon/kafka/KafkaDsl.scala b/cornichon-kafka/src/main/scala/com/github/agourlay/cornichon/kafka/KafkaDsl.scala
index 0142f3f8c..f3f9a2597 100644
--- a/cornichon-kafka/src/main/scala/com/github/agourlay/cornichon/kafka/KafkaDsl.scala
+++ b/cornichon-kafka/src/main/scala/com/github/agourlay/cornichon/kafka/KafkaDsl.scala
@@ -67,7 +67,6 @@ trait KafkaDsl {
       if (messages.size < atLeastAmount)
         NotEnoughMessagesPolled(atLeastAmount, messages.toList).asLeft
       else {
-        messages.drop(messages.size - atLeastAmount)
         val newSession = messages.foldLeft(sc.session) { (session, value) =>
           commonSessionExtraction(session, topic, value).valueUnsafe
         }
@@ -76,7 +75,7 @@ trait KafkaDsl {
     }
   )
 
-  def kafka(topic: String) = KafkaStepBuilder(sessionKey = topic)
+  def kafka(topic: String): KafkaStepBuilder = KafkaStepBuilder(sessionKey = topic)
 
   private def commonSessionExtraction(session: Session, topic: String, response: ConsumerRecord[String, String]) =
     session.addValues(
diff --git a/cornichon-scalatest/src/main/scala/com/github/agourlay/cornichon/scalatest/ScalatestFeature.scala b/cornichon-scalatest/src/main/scala/com/github/agourlay/cornichon/scalatest/ScalatestFeature.scala
index 7c398e841..2d550b7a2 100644
--- a/cornichon-scalatest/src/main/scala/com/github/agourlay/cornichon/scalatest/ScalatestFeature.scala
+++ b/cornichon-scalatest/src/main/scala/com/github/agourlay/cornichon/scalatest/ScalatestFeature.scala
@@ -6,31 +6,29 @@ import com.github.agourlay.cornichon.core._
 import com.github.agourlay.cornichon.dsl.BaseFeature
 import com.github.agourlay.cornichon.dsl.BaseFeature.shutDownGlobalResources
 import com.github.agourlay.cornichon.scalatest.ScalatestFeature._
-
 import org.scalatest._
 import org.scalatest.wordspec.AsyncWordSpecLike
 
 import java.util
 import java.util.concurrent.atomic.AtomicInteger
-
-import scala.concurrent.Future
+import scala.concurrent.{ Await, Future }
 import scala.concurrent.duration._
 import scala.util.{ Failure, Success, Try }
 
 trait ScalatestFeature extends AsyncWordSpecLike with BeforeAndAfterAll with ParallelTestExecution {
   this: BaseFeature =>
 
-  override def beforeAll() = {
+  override def beforeAll(): Unit = {
     reserveGlobalRuntime()
     beforeFeature.foreach(f => f())
   }
 
-  override def afterAll() = {
+  override def afterAll(): Unit = {
     afterFeature.foreach(f => f())
     releaseGlobalRuntime()
   }
 
-  override def run(testName: Option[String], args: Args) =
+  override def run(testName: Option[String], args: Args): Status =
     if (executeScenariosInParallel) super.run(testName, args)
     else super.run(testName, args.copy(distributor = None))
 
@@ -96,14 +94,16 @@ object ScalatestFeature {
   private val registeredUsage = new AtomicInteger
   private val safePassInRow = new AtomicInteger
 
-  // Custom Reaper process for the time being as we want to cleanup after all Feature
+  // Custom Reaper process for the time being as we want to clean up after all Feature
   // Will tear down stuff if no Feature registers during 10 secs
   private val timer = new util.Timer()
   private val timerTask = new util.TimerTask {
     def run(): Unit = {
       if (registeredUsage.get() == 0) {
         safePassInRow.incrementAndGet()
-        if (safePassInRow.get() == 2) { shutDownGlobalResources(); () } else ()
+        if (safePassInRow.get() == 2) {
+          Await.result(shutDownGlobalResources(), Duration.Inf)
+        }
       } else if (safePassInRow.get() > 0) {
         safePassInRow.decrementAndGet()
         ()
diff --git a/cornichon-test-framework/src/main/scala/com/github/agourlay/cornichon/framework/CornichonFeatureSbtTask.scala b/cornichon-test-framework/src/main/scala/com/github/agourlay/cornichon/framework/CornichonFeatureSbtTask.scala
index efdf02401..0b8b70146 100644
--- a/cornichon-test-framework/src/main/scala/com/github/agourlay/cornichon/framework/CornichonFeatureSbtTask.scala
+++ b/cornichon-test-framework/src/main/scala/com/github/agourlay/cornichon/framework/CornichonFeatureSbtTask.scala
@@ -15,7 +15,7 @@ class CornichonFeatureSbtTask(task: TaskDef, scenarioNameFilter: Set[String], ex
   override def execute(eventHandler: EventHandler, loggers: Array[Logger]): Array[Task] = {
     val fqn = task.fullyQualifiedName()
     val featureInfo = FeatureInfo(fqn, Class.forName(fqn), task.fingerprint(), task.selectors().head)
-    val featureTask = loadAndExecute(featureInfo, eventHandler, explicitSeed, scenarioNameFilter)
+    val featureTask = loadAndExecute(featureInfo, eventHandler, explicitSeed, scenarioNameFilter).map(_ => ())
     Await.result(featureTask.unsafeToFuture(), Duration.Inf)
     Array.empty
   }
diff --git a/cornichon-test-framework/src/main/scala/com/github/agourlay/cornichon/framework/JUnitXmlReporter.scala b/cornichon-test-framework/src/main/scala/com/github/agourlay/cornichon/framework/JUnitXmlReporter.scala
index 64714512a..66e4dca17 100644
--- a/cornichon-test-framework/src/main/scala/com/github/agourlay/cornichon/framework/JUnitXmlReporter.scala
+++ b/cornichon-test-framework/src/main/scala/com/github/agourlay/cornichon/framework/JUnitXmlReporter.scala
@@ -6,13 +6,14 @@ import java.io.{ File, PrintWriter }
 import java.net.{ InetAddress, UnknownHostException }
 import java.text.SimpleDateFormat
 import java.util.Properties
-
 import sbt.testing.{ Event, Status }
 
+import scala.annotation.nowarn
 import scala.collection.mutable.ListBuffer
 import scala.concurrent.duration.FiniteDuration
 
 // Freely adapted from Scalatest's "org.scalatest.tools.JUnitXmlReporter"
+@nowarn("msg=unused value of type scala.xml.NodeBuffer")
 object JUnitXmlReporter {
 
   private lazy val propertiesXml = genPropertiesXml