Add MIMA checks to ensure binary compatibility

build.sbt

@@ -1,4 +1,15 @@
 import sbt.Def
+import MimaSettings.mimaSettings
+
+/**
+ * As of zio-kafka version 2.8.0 releases are binary compatible. This is checked with Mima.
+ *
+ * Keep this value set to the oldest minor release (with patch version set to "0") that is still binary compatible.
+ *
+ * Set this value to `None` when master is _not_ binary compatible with the latest minor release, the next release shall
+ * increase the minor version.
+ */
+lazy val binCompatVersionToCompare = None // Some("2.8.0")
 
 lazy val kafkaVersion         = "3.7.0"
 lazy val embeddedKafkaVersion = "3.7.0" // Should be the same as kafkaVersion, except for the patch part
@@ -66,9 +77,10 @@ val excludeInferAny = { options: Seq[String] => options.filterNot(Set("-Xlint:in
 lazy val root = project
   .in(file("."))
   .settings(
-    name               := "zio-kafka",
-    publish / skip     := true,
-    crossScalaVersions := Nil // https://www.scala-sbt.org/1.x/docs/Cross-Build.html#Cross+building+a+project+statefully
+    name           := "zio-kafka",
+    publish / skip := true,
+    crossScalaVersions := Nil, // https://www.scala-sbt.org/1.x/docs/Cross-Build.html#Cross+building+a+project+statefully,
+    commands += lint
   )
   .aggregate(
     zioKafka,
@@ -104,6 +116,7 @@ lazy val zioKafka =
     .enablePlugins(BuildInfoPlugin)
     .settings(stdSettings("zio-kafka"))
     .settings(buildInfoSettings("zio.kafka"))
+    .settings(mimaSettings(binCompatVersionToCompare, failOnProblem = true))
     .settings(enableZIO(enableStreaming = true))
     .settings(
       libraryDependencies ++= Seq(
@@ -126,6 +139,7 @@ lazy val zioKafkaTestkit =
     .dependsOn(zioKafka)
     .enablePlugins(BuildInfoPlugin)
     .settings(stdSettings("zio-kafka-testkit"))
+    .settings(mimaSettings(binCompatVersionToCompare, failOnProblem = false))
     .settings(
       libraryDependencies ++= Seq(
         "dev.zio" %% "zio"      % zioVersion.value,
@@ -187,6 +201,7 @@ lazy val zioKafkaExample =
 
 addCommandAlias("fmt", "all scalafmtSbt scalafmt test:scalafmt")
 addCommandAlias("check", "all scalafmtSbtCheck scalafmtCheck test:scalafmtCheck")
+addCommandAlias("mimaCheck", "+zioKafka/mimaReportBinaryIssues;+zioKafkaTestkit/mimaReportBinaryIssues")
 
 lazy val docs = project
   .in(file("zio-kafka-docs"))
@@ -206,3 +221,9 @@ lazy val docs = project
   )
   .enablePlugins(WebsitePlugin)
   .dependsOn(zioKafka, zioKafkaTestkit)
+
+// Extend 'lint' with mimaCheck
+lazy val lint = {
+  val defaultLint = zio.sbt.Commands.ComposableCommand.lint
+  defaultLint.copy(commandStrings = defaultLint.commandStrings :+ "mimaCheck").toCommand
+}

project/MimaSettings.scala

@@ -0,0 +1,24 @@
+import com.typesafe.tools.mima.core.*
+import com.typesafe.tools.mima.core.ProblemFilters.*
+import com.typesafe.tools.mima.plugin.MimaKeys.*
+import sbt.*
+import sbt.Keys.{ name, organization }
+
+object MimaSettings {
+
+  def mimaSettings(binCompatVersionToCompare: Option[String], failOnProblem: Boolean): Seq[Def.Setting[?]] =
+    binCompatVersionToCompare match {
+      case None =>
+        Seq(mimaPreviousArtifacts := Set.empty)
+      case Some(binCompatVersion) =>
+        Seq(
+          mimaPreviousArtifacts := Set(organization.value %% name.value % binCompatVersion),
+          mimaBinaryIssueFilters ++= Seq(
+            exclude[Problem]("zio.kafka.consumer.internal.*")
+          ),
+          mimaFailOnProblem := failOnProblem
+        )
+
+    }
+
+}

project/plugins.sbt

@@ -7,5 +7,6 @@ addSbtPlugin("dev.zio" % "zio-sbt-ci"        % zioSbtVersion)
 addSbtPlugin("ch.epfl.scala"  % "sbt-scalafix"        % "0.12.0")
 addSbtPlugin("org.typelevel"  % "sbt-tpolecat"        % "0.5.1")
 addSbtPlugin("com.github.sbt" % "sbt-native-packager" % "1.10.0")
+addSbtPlugin("com.typesafe"   % "sbt-mima-plugin"     % "1.1.3")
 
 resolvers ++= Resolver.sonatypeOssRepos("public")