diff --git a/buildfile/src/main/scala/sbt/internal/EvaluateConfigurations.scala b/buildfile/src/main/scala/sbt/internal/EvaluateConfigurations.scala
index 8df2ef103..d3a630b10 100644
--- a/buildfile/src/main/scala/sbt/internal/EvaluateConfigurations.scala
+++ b/buildfile/src/main/scala/sbt/internal/EvaluateConfigurations.scala
@@ -393,8 +393,7 @@ object Index {
         case (k, xs) if xs.size > 1 => (k, xs)
       }
       .toVector
-    if (duplicates.isEmpty)
-      multiMap.collect { case (k, v) if validID(k) => (k, v.head) } toMap
+    if duplicates.isEmpty then multiMap.collect { case (k, v) if validID(k) => (k, v.head) }.toMap
     else
       sys.error(
         duplicates map { case (k, tps) =>
diff --git a/main-settings/src/main/scala/sbt/Scope.scala b/main-settings/src/main/scala/sbt/Scope.scala
index 99fcbb2c4..6b643b513 100644
--- a/main-settings/src/main/scala/sbt/Scope.scala
+++ b/main-settings/src/main/scala/sbt/Scope.scala
@@ -408,9 +408,11 @@ object Scope {
       projectInherit: ProjectRef => Seq[ProjectRef],
       configInherit: (ResolvedReference, ConfigKey) => Seq[ConfigKey]
   ): DelegateIndex = {
-    val pDelegates = refs map { case (ref, project) =>
-      (ref, delegateIndex(ref, configurations(project))(projectInherit, configInherit))
-    } toMap;
+    val pDelegates = refs
+      .map:
+        case (ref, project) =>
+          (ref, delegateIndex(ref, configurations(project))(projectInherit, configInherit))
+      .toMap
     new DelegateIndex0(pDelegates)
   }
   private[this] def delegateIndex(ref: ProjectRef, confs: Seq[ConfigKey])(
diff --git a/main/src/main/scala/sbt/Cross.scala b/main/src/main/scala/sbt/Cross.scala
index aa11c1204..0169bd19d 100644
--- a/main/src/main/scala/sbt/Cross.scala
+++ b/main/src/main/scala/sbt/Cross.scala
@@ -86,7 +86,7 @@ object Cross {
   private def crossRestoreSessionParser: Parser[String] = token(CrossRestoreSessionCommand)
 
   private[sbt] def requireSession[T](p: State => Parser[T]): State => Parser[T] =
-    s => if (s get sessionSettings isEmpty) failure("No project loaded") else p(s)
+    s => if s.get(sessionSettings).isEmpty then failure("No project loaded") else p(s)
 
   private def resolveAggregates(extracted: Extracted): Seq[ProjectRef] = {
 
diff --git a/main/src/main/scala/sbt/Defaults.scala b/main/src/main/scala/sbt/Defaults.scala
index cf346cb90..e30eec786 100644
--- a/main/src/main/scala/sbt/Defaults.scala
+++ b/main/src/main/scala/sbt/Defaults.scala
@@ -2944,8 +2944,8 @@ object Classpaths {
       unmanagedJars := findUnmanagedJars(
         configuration.value,
         unmanagedBase.value,
-        (unmanagedJars / includeFilter) value,
-        (unmanagedJars / excludeFilter) value,
+        (unmanagedJars / includeFilter).value,
+        (unmanagedJars / excludeFilter).value,
         fileConverter.value,
       )
     ).map(exportVirtualClasspath) ++ Seq(
@@ -3606,7 +3606,7 @@ object Classpaths {
 
   private[sbt] def defaultProjectID: Initialize[ModuleID] = Def.setting {
     val p0 = ModuleID(organization.value, moduleName.value, version.value)
-      .cross((projectID / crossVersion) value)
+      .cross((projectID / crossVersion).value)
       .artifacts(artifacts.value: _*)
     val p1 = apiURL.value match {
       case Some(u) => p0.extra(SbtPomExtraProperties.POM_API_KEY -> u.toExternalForm)
@@ -4227,7 +4227,7 @@ object Classpaths {
       (proj / ivyModule).get(data)
     }.join
     ivyModules.mapN { mod =>
-      mod map { _.dependencyMapping(log) } toMap;
+      mod.map { _.dependencyMapping(log) }.toMap
     }
 
   def projectResolverTask: Initialize[Task[Resolver]] =
diff --git a/main/src/main/scala/sbt/ProjectExtra.scala b/main/src/main/scala/sbt/ProjectExtra.scala
index 723d11b9d..5a7e03086 100755
--- a/main/src/main/scala/sbt/ProjectExtra.scala
+++ b/main/src/main/scala/sbt/ProjectExtra.scala
@@ -304,11 +304,11 @@ trait ProjectExtra extends Scoped.Syntax:
       val msg = (ref / Keys.onLoadMessage) get structure.data getOrElse ""
       if (!msg.isEmpty) s.log.info(msg)
       def get[T](k: SettingKey[T]): Option[T] = (ref / k) get structure.data
-      def commandsIn(axis: ResolvedReference) = (axis / commands) get structure.data toList
+      def commandsIn(axis: ResolvedReference) = (axis / commands).get(structure.data).toList
 
       val allCommands = commandsIn(ref) ++ commandsIn(
         BuildRef(ref.build)
-      ) ++ ((Global / commands) get structure.data toList)
+      ) ++ (Global / commands).get(structure.data).toList
       val history = get(historyPath).flatMap(identity)
       val prompt = get(shellPrompt)
       val newPrompt = get(colorShellPrompt)
diff --git a/main/src/main/scala/sbt/Resolvers.scala b/main/src/main/scala/sbt/Resolvers.scala
index d7470aec9..4bee75e27 100644
--- a/main/src/main/scala/sbt/Resolvers.scala
+++ b/main/src/main/scala/sbt/Resolvers.scala
@@ -138,7 +138,7 @@ object Resolvers {
       if (Util.isNonCygwinWindows) "cmd" +: "/c" +: command
       else command,
       cwd
-    ) !;
+    ).!
     if (result != 0)
       sys.error("Nonzero exit code (" + result + "): " + command.mkString(" "))
   }
diff --git a/main/src/main/scala/sbt/ScriptedPlugin.scala b/main/src/main/scala/sbt/ScriptedPlugin.scala
index 6db60e4ce..97a84613e 100644
--- a/main/src/main/scala/sbt/ScriptedPlugin.scala
+++ b/main/src/main/scala/sbt/ScriptedPlugin.scala
@@ -32,8 +32,8 @@ object ScriptedPlugin extends AutoPlugin {
   sys.props(org.apache.logging.log4j.util.LoaderUtil.IGNORE_TCCL_PROPERTY) = "true"
 
   object autoImport {
-    val ScriptedConf = Configurations.config("scripted-sbt") hide
-    val ScriptedLaunchConf = Configurations.config("scripted-sbt-launch") hide
+    val ScriptedConf = Configurations.config("scripted-sbt").hide
+    val ScriptedLaunchConf = Configurations.config("scripted-sbt-launch").hide
 
     val scriptedSbt = settingKey[String]("")
     val sbtLauncher = taskKey[File]("")
diff --git a/main/src/main/scala/sbt/internal/Act.scala b/main/src/main/scala/sbt/internal/Act.scala
index 87acf5f7d..21fba1c13 100644
--- a/main/src/main/scala/sbt/internal/Act.scala
+++ b/main/src/main/scala/sbt/internal/Act.scala
@@ -596,7 +596,7 @@ object Act {
     else data.get(scope, key)
 
   def requireSession[T](s: State, p: => Parser[T]): Parser[T] =
-    if (s get sessionSettings isEmpty) failure("No project loaded") else p
+    if s.get(sessionSettings).isEmpty then failure("No project loaded") else p
 
   sealed trait ParsedAxis[+T] {
     final def isExplicit = this != Omitted
diff --git a/main/src/main/scala/sbt/internal/Aggregation.scala b/main/src/main/scala/sbt/internal/Aggregation.scala
index 79ff24bf9..7550393bf 100644
--- a/main/src/main/scala/sbt/internal/Aggregation.scala
+++ b/main/src/main/scala/sbt/internal/Aggregation.scala
@@ -96,8 +96,8 @@ object Aggregation {
 
     val extracted = Project extract s
     import extracted.structure
-    val toRun = ts map { case KeyValue(k, t) => t.map(v => KeyValue(k, v)) } join;
-    val roots = ts map { case KeyValue(k, _) => k }
+    val toRun = ts.map { case KeyValue(k, t) => t.map(v => KeyValue(k, v)) }.join
+    val roots = ts.map { case KeyValue(k, _) => k }
     val config = extractedTaskConfig(extracted, structure, s)
 
     val start = System.currentTimeMillis
diff --git a/main/src/main/scala/sbt/internal/ClasspathImpl.scala b/main/src/main/scala/sbt/internal/ClasspathImpl.scala
index 36bfd5537..2304675e4 100644
--- a/main/src/main/scala/sbt/internal/ClasspathImpl.scala
+++ b/main/src/main/scala/sbt/internal/ClasspathImpl.scala
@@ -431,7 +431,7 @@ private[sbt] object ClasspathImpl {
   }
 
   def union[A, B](maps: Seq[A => Seq[B]]): A => Seq[B] =
-    a => maps.foldLeft(Seq[B]()) { _ ++ _(a) } distinct;
+    a => maps.foldLeft(Seq[B]()) { _ ++ _(a) }.distinct
 
   def parseList(s: String, allConfs: Seq[String]): Seq[String] =
     (trim(s split ",") flatMap replaceWildcard(allConfs)).distinct
diff --git a/main/src/main/scala/sbt/internal/Load.scala b/main/src/main/scala/sbt/internal/Load.scala
index 873899eb6..f8b914b5f 100755
--- a/main/src/main/scala/sbt/internal/Load.scala
+++ b/main/src/main/scala/sbt/internal/Load.scala
@@ -1466,9 +1466,10 @@ private[sbt] object Load {
   def initialSession(structure: BuildStructure, rootEval: () => Eval, s: State): SessionSettings = {
     val session = s get Keys.sessionSettings
     val currentProject = session map (_.currentProject) getOrElse Map.empty
-    val currentBuild = session map (_.currentBuild) filter (uri =>
-      structure.units.keys exists (uri ==)
-    ) getOrElse structure.root
+    val currentBuild = session
+      .map(_.currentBuild)
+      .filter(uri => structure.units.keys.exists(uri == _))
+      .getOrElse(structure.root)
     new SessionSettings(
       currentBuild,
       projectMap(structure, currentProject),
diff --git a/main/src/main/scala/sbt/internal/PluginDiscovery.scala b/main/src/main/scala/sbt/internal/PluginDiscovery.scala
index ba6133047..091b0a780 100644
--- a/main/src/main/scala/sbt/internal/PluginDiscovery.scala
+++ b/main/src/main/scala/sbt/internal/PluginDiscovery.scala
@@ -183,9 +183,9 @@ object PluginDiscovery:
 
   private[this] def incompatiblePlugins(data: PluginData, t: LinkageError): Nothing = {
     val evicted = data.report.toList.flatMap(_.configurations.flatMap(_.evicted))
-    val evictedModules = evicted map { id =>
+    val evictedModules = evicted.map { id =>
       (id.organization, id.name)
-    } distinct;
+    }.distinct
     val evictedStrings = evictedModules map { case (o, n) => o + ":" + n }
     val msgBase = "Binary incompatibility in plugins detected."
     val msgExtra =
diff --git a/main/src/main/scala/sbt/internal/PluginsDebug.scala b/main/src/main/scala/sbt/internal/PluginsDebug.scala
index 9c586dcad..50280ffab 100644
--- a/main/src/main/scala/sbt/internal/PluginsDebug.scala
+++ b/main/src/main/scala/sbt/internal/PluginsDebug.scala
@@ -384,7 +384,7 @@ private[sbt] object PluginsDebug {
 
   private[this] def includeAll[T <: Basic](basic: Set[T]): Plugins = And(basic.toList)
   private[this] def excludeAll(plugins: Set[AutoPlugin]): Plugins =
-    And(plugins map (p => Exclude(p)) toList)
+    And(plugins.map(p => Exclude(p)).toList)
 
   private[this] def excludes(bs: Seq[Basic]): Set[AutoPlugin] =
     bs.collect { case Exclude(b) => b }.toSet
diff --git a/main/src/main/scala/sbt/internal/ProjectNavigation.scala b/main/src/main/scala/sbt/internal/ProjectNavigation.scala
index 7d4387d50..04e7cf324 100644
--- a/main/src/main/scala/sbt/internal/ProjectNavigation.scala
+++ b/main/src/main/scala/sbt/internal/ProjectNavigation.scala
@@ -16,7 +16,7 @@ import sbt.ProjectExtra.{ extract, updateCurrent }
 
 object ProjectNavigation {
   def command(s: State): Parser[() => State] =
-    if (s get sessionSettings isEmpty) failure("No project loaded")
+    if s.get(sessionSettings).isEmpty then failure("No project loaded")
     else (new ProjectNavigation(s)).command
 }
 
diff --git a/main/src/main/scala/sbt/internal/server/BuildServerProtocol.scala b/main/src/main/scala/sbt/internal/server/BuildServerProtocol.scala
index e11ea4a36..7459f6072 100644
--- a/main/src/main/scala/sbt/internal/server/BuildServerProtocol.scala
+++ b/main/src/main/scala/sbt/internal/server/BuildServerProtocol.scala
@@ -866,8 +866,8 @@ object BuildServerProtocol {
     }
   }
 
-  private val jsonParser: Parser[JValue] = (Parsers.any *).map(_.mkString)
-  .map(JsonParser.parseUnsafe)
+  private val jsonParser: Parser[JValue] = (Parsers.any.*).map(_.mkString)
+    .map(JsonParser.parseUnsafe)
 
   private def bspRunTask: Def.Initialize[InputTask[Unit]] =
     Def.input((s: State) => jsonParser).flatMapTask { json =>
diff --git a/main/src/test/scala/sbt/internal/TestBuild.scala b/main/src/test/scala/sbt/internal/TestBuild.scala
index b1af50eba..3fd5758f3 100644
--- a/main/src/test/scala/sbt/internal/TestBuild.scala
+++ b/main/src/test/scala/sbt/internal/TestBuild.scala
@@ -189,9 +189,7 @@ abstract class TestBuild {
   }
 
   def mapBy[K, T](s: Seq[T])(f: T => K): Map[K, T] =
-    s map { t =>
-      (f(t), t)
-    } toMap;
+    s.map(t => (f(t), t)).toMap
 
   lazy val keysGen: Gen[TestKeys] =
     for {
diff --git a/project/HouseRulesPlugin.scala b/project/HouseRulesPlugin.scala
index a83e88b83..036b4a967 100644
--- a/project/HouseRulesPlugin.scala
+++ b/project/HouseRulesPlugin.scala
@@ -9,28 +9,28 @@ object HouseRulesPlugin extends AutoPlugin {
 
   lazy val baseSettings: Seq[Def.Setting[_]] = Seq(
     scalacOptions ++= Seq("-encoding", "utf8"),
-    scalacOptions ++= Seq("-deprecation", "-feature", "-unchecked", "-Xlint"),
+    scalacOptions ++= Seq("-deprecation", "-feature", "-unchecked"),
     scalacOptions += "-language:higherKinds",
     scalacOptions += "-language:implicitConversions",
     scalacOptions ++= "-Xfuture".ifScala213OrMinus.value.toList,
-    scalacOptions += "-Xlint",
+    scalacOptions ++= "-Xlint".ifScala2.value.toList,
+    // TODO: uncomment once we can build without warnings on Scala 3
     // scalacOptions ++= "-Xfatal-warnings"
-    //   .ifScala(v => {
+    //   .ifScala3x(_ => {
     //     sys.props.get("sbt.build.fatal") match {
     //       case Some(_) => java.lang.Boolean.getBoolean("sbt.build.fatal")
-    //       case _       => v == 12
+    //       case _       => true
     //     }
     //   })
     //   .value
     //   .toList,
     scalacOptions ++= "-Ykind-projector".ifScala3.value.toList,
-    scalacOptions ++= "-Ysemanticdb".ifScala3.value.toList,
     scalacOptions ++= "-Yinline-warnings".ifScala211OrMinus.value.toList,
     scalacOptions ++= "-Yno-adapted-args".ifScala212OrMinus.value.toList,
-    scalacOptions += "-Ywarn-dead-code",
-    scalacOptions += "-Ywarn-numeric-widen",
-    scalacOptions += "-Ywarn-value-discard",
-    scalacOptions ++= "-Ywarn-unused-import".ifScala(v => 11 <= v && v <= 12).value.toList
+    scalacOptions ++= "-Ywarn-dead-code".ifScala2.value.toList,
+    scalacOptions ++= "-Ywarn-numeric-widen".ifScala2.value.toList,
+    scalacOptions ++= "-Ywarn-value-discard".ifScala2.value.toList,
+    scalacOptions ++= "-Ywarn-unused-import".ifScala2x(v => 11 <= v && v <= 12).value.toList
   ) ++ Seq(Compile, Test).flatMap(c =>
     (c / console / scalacOptions) --= Seq("-Ywarn-unused-import", "-Xlint")
   )
@@ -38,14 +38,17 @@ object HouseRulesPlugin extends AutoPlugin {
   private def scalaPartV = Def setting (CrossVersion partialVersion scalaVersion.value)
 
   private implicit final class AnyWithIfScala[A](val __x: A) {
-    def ifScala(p: Long => Boolean) =
-      Def setting (scalaPartV.value collect { case (2, y) if p(y) => __x })
-    def ifScalaLte(v: Long) = ifScala(_ <= v)
-    def ifScalaGte(v: Long) = ifScala(_ >= v)
+    def ifScala2x(p: Long => Boolean) =
+      Def.setting(scalaPartV.value collect { case (2, y) if p(y) => __x })
+    def ifScala3x(p: Long => Boolean) =
+      Def.setting(scalaPartV.value collect { case (3, y) if p(y) => __x })
+    def ifScalaLte(v: Long) = ifScala2x(_ <= v)
+    def ifScalaGte(v: Long) = ifScala2x(_ >= v)
     def ifScala211OrMinus = ifScalaLte(11)
     def ifScala211OrPlus = ifScalaGte(11)
     def ifScala212OrMinus = ifScalaLte(12)
     def ifScala213OrMinus = ifScalaLte(13)
+    def ifScala2 = ifScala2x(_ => true)
     def ifScala3 = Def.setting(
       if (scalaBinaryVersion.value == "3") Seq(__x)
       else Nil
diff --git a/project/Util.scala b/project/Util.scala
index b32a9ee11..53d59d0c0 100644
--- a/project/Util.scala
+++ b/project/Util.scala
@@ -26,14 +26,6 @@ object Util {
   )
 
   lazy val baseScalacOptions = Seq(
-    scalacOptions ++= Seq(
-      "-Xelide-below",
-      "0",
-      "-language:existentials",
-      "-language:postfixOps",
-      "-Yrangepos",
-      "-Wconf:cat=unused-nowarn:s",
-    ),
     Compile / doc / scalacOptions -= "-Xlint",
     Compile / doc / scalacOptions -= "-Xfatal-warnings",
   )