diff --git a/buildfile/src/main/scala/sbt/internal/parser/SbtParser.scala b/buildfile/src/main/scala/sbt/internal/parser/SbtParser.scala
index b3e0de9c9..b6793d29d 100644
--- a/buildfile/src/main/scala/sbt/internal/parser/SbtParser.scala
+++ b/buildfile/src/main/scala/sbt/internal/parser/SbtParser.scala
@@ -236,7 +236,7 @@ private[sbt] case class SbtParser(path: VirtualFileRef, lines: Seq[String])
                       |$code
                       |}""".stripMargin
     val fileName = path.id
-    val reporterId = s"$fileName-${Random.nextInt}"
+    val reporterId = s"$fileName-${Random.nextInt()}"
     val sourceFile = SourceFile(
       VirtualFile(reporterId, wrapCode.getBytes(StandardCharsets.UTF_8)),
       scala.io.Codec.UTF8
diff --git a/buildfile/src/test/scala/sbt/internal/parser/SbtParserErrorSpec.scala b/buildfile/src/test/scala/sbt/internal/parser/SbtParserErrorSpec.scala
index 827260e8a..e8cc39b05 100644
--- a/buildfile/src/test/scala/sbt/internal/parser/SbtParserErrorSpec.scala
+++ b/buildfile/src/test/scala/sbt/internal/parser/SbtParserErrorSpec.scala
@@ -29,7 +29,7 @@ object SbtParserErrorSpec extends AbstractSpec {
       print(s"Processing ${file.getFileName}: ")
 
       val vf = converter.toVirtualFile(file)
-      val buildSbt = Source.fromFile(file.toUri).getLines.toSeq
+      val buildSbt = Source.fromFile(file.toUri).getLines().toSeq
       val message = interceptMessageException(SbtParser(vf, buildSbt))
       println(message)
       assert(message.contains(file.getFileName.toString))
diff --git a/launcher-package/integration-test/src/test/scala/ShellScriptUtil.scala b/launcher-package/integration-test/src/test/scala/ShellScriptUtil.scala
index 960c1570a..3a1d2aaca 100644
--- a/launcher-package/integration-test/src/test/scala/ShellScriptUtil.scala
+++ b/launcher-package/integration-test/src/test/scala/ShellScriptUtil.scala
@@ -179,9 +179,9 @@ trait ShellScriptUtil extends BasicTestSuite {
                 BasicIO.processFully(processLine)
               )
             )
-          if p.exitValue != 0 then
+          if p.exitValue() != 0 then
             lines.foreach(l => Console.err.println(l))
-            sys.error(s"process exit with ${p.exitValue}")
+            sys.error(s"process exit with ${p.exitValue()}")
           f(lines.toList)
           ()
         finally
diff --git a/main-actions/src/main/scala/sbt/ForkTests.scala b/main-actions/src/main/scala/sbt/ForkTests.scala
index 9bdfcc94a..08590ed08 100755
--- a/main-actions/src/main/scala/sbt/ForkTests.scala
+++ b/main-actions/src/main/scala/sbt/ForkTests.scala
@@ -215,7 +215,7 @@ private class React(
       case NonFatal(_)            => ()
 
   override def notifyExit(p: Process): Unit =
-    if !process.isAlive && !promise.isCompleted then
+    if !process.isAlive() && !promise.isCompleted then
       val exitCode = process.exitValue()
       if exitCode != 0 then
         promise.failure(new RuntimeException(s"Forked test process exited with code $exitCode"))
diff --git a/main-actions/src/main/scala/sbt/internal/WorkerExchange.scala b/main-actions/src/main/scala/sbt/internal/WorkerExchange.scala
index f4ce25e1c..6e91c6636 100644
--- a/main-actions/src/main/scala/sbt/internal/WorkerExchange.scala
+++ b/main-actions/src/main/scala/sbt/internal/WorkerExchange.scala
@@ -109,7 +109,7 @@ class WorkerProxy(
     input.close()
     serverSocket.foreach(_.close())
   def blockForExitCode(): Int =
-    if !process.isAlive then process.exitValue()
+    if !process.isAlive() then process.exitValue()
     else Fork.blockForExitCode(process)
 
   /** print a line into stdin of the worker process. */
diff --git a/main/src/main/scala/sbt/internal/AbstractTaskExecuteProgress.scala b/main/src/main/scala/sbt/internal/AbstractTaskExecuteProgress.scala
index 00163a4b6..284c9f273 100644
--- a/main/src/main/scala/sbt/internal/AbstractTaskExecuteProgress.scala
+++ b/main/src/main/scala/sbt/internal/AbstractTaskExecuteProgress.scala
@@ -68,7 +68,7 @@ private[sbt] abstract class AbstractTaskExecuteProgress(
     timings.forEach { (task, timing) =>
       if (timing.isActive) result += task -> (now - timing.startNanos).nanos
     }
-    result.result
+    result.result()
   }
 
   override def afterRegistered(
diff --git a/main/src/main/scala/sbt/internal/CommandExchange.scala b/main/src/main/scala/sbt/internal/CommandExchange.scala
index fa14e463d..7ba2681fa 100644
--- a/main/src/main/scala/sbt/internal/CommandExchange.scala
+++ b/main/src/main/scala/sbt/internal/CommandExchange.scala
@@ -101,7 +101,7 @@ private[sbt] final class CommandExchange {
           Option(deadline match {
             case Some(d: Deadline) =>
               commandQueue.poll(d.timeLeft.toMillis + 1, TimeUnit.MILLISECONDS) match {
-                case null if idleDeadline.fold(false)(_.isOverdue) =>
+                case null if idleDeadline.fold(false)(_.isOverdue()) =>
                   state.foreach { s =>
                     s.get(BasicKeys.serverIdleTimeout) match {
                       case Some(Some(d)) => s.log.info(s"sbt idle timeout of $d expired")
diff --git a/main/src/main/scala/sbt/internal/Continuous.scala b/main/src/main/scala/sbt/internal/Continuous.scala
index 8b1a018bf..dc7ad8a5c 100644
--- a/main/src/main/scala/sbt/internal/Continuous.scala
+++ b/main/src/main/scala/sbt/internal/Continuous.scala
@@ -503,7 +503,7 @@ private[sbt] object Continuous {
              * increase in latency.
              */
             @tailrec def aggregate(res: Seq[Event]): Seq[Event] =
-              if (limit.isOverdue) res
+              if (limit.isOverdue()) res
               else {
                 monitor.poll(antiEntropyPollPeriod) match {
                   case s if s.nonEmpty => aggregate(res ++ s)
diff --git a/main/src/main/scala/sbt/internal/DefaultBackgroundJobService.scala b/main/src/main/scala/sbt/internal/DefaultBackgroundJobService.scala
index 061daa52e..841f94002 100644
--- a/main/src/main/scala/sbt/internal/DefaultBackgroundJobService.scala
+++ b/main/src/main/scala/sbt/internal/DefaultBackgroundJobService.scala
@@ -194,7 +194,7 @@ private[sbt] abstract class AbstractBackgroundJobService extends BackgroundJobSe
   override final def close(): Unit = shutdown()
   override def shutdown(): Unit = {
     val deadline = 10.seconds.fromNow
-    while (jobSet.nonEmpty && !deadline.isOverdue) {
+    while (jobSet.nonEmpty && !deadline.isOverdue()) {
       jobSet.headOption.foreach { handle =>
         if (handle.job.isRunning()) {
           handle.job.shutdown()
diff --git a/main/src/main/scala/sbt/internal/TaskProgress.scala b/main/src/main/scala/sbt/internal/TaskProgress.scala
index 54f708d3a..d9daedcd2 100644
--- a/main/src/main/scala/sbt/internal/TaskProgress.scala
+++ b/main/src/main/scala/sbt/internal/TaskProgress.scala
@@ -86,7 +86,7 @@ private[sbt] class TaskProgress(
 
   private def doReport(): Unit = {
     val runnable: Runnable = () => {
-      if (nextReport.get.isOverdue) {
+      if (nextReport.get.isOverdue()) {
         report()
       }
     }
diff --git a/main/src/main/scala/sbt/internal/server/Definition.scala b/main/src/main/scala/sbt/internal/server/Definition.scala
index fd770d9a9..0521d580b 100644
--- a/main/src/main/scala/sbt/internal/server/Definition.scala
+++ b/main/src/main/scala/sbt/internal/server/Definition.scala
@@ -219,7 +219,7 @@ private[sbt] object Definition {
   }
 
   private[sbt] def getAnalyses: Future[Seq[Analysis]] = {
-    val result = Promise[Seq[Analysis]]
+    val result = Promise[Seq[Analysis]]()
 
     new Thread("sbt-get-analysis-thread") {
       setDaemon(true)
diff --git a/main/src/main/scala/sbt/internal/server/NetworkChannel.scala b/main/src/main/scala/sbt/internal/server/NetworkChannel.scala
index d1ba86f93..d053e329c 100644
--- a/main/src/main/scala/sbt/internal/server/NetworkChannel.scala
+++ b/main/src/main/scala/sbt/internal/server/NetworkChannel.scala
@@ -766,7 +766,7 @@ final class NetworkChannel(
     private def empty = TerminalPropertiesResponse(0, 0, false, false, false, false)
     def getProperties(block: Boolean): Unit = {
       if (alive.get) {
-        if (!pending.get && Option(lastUpdate.get).fold(true)(d => (d + 1.second).isOverdue)) {
+        if (!pending.get && Option(lastUpdate.get).fold(true)(d => (d + 1.second).isOverdue())) {
           pending.set(true)
           val queue = VirtualTerminal.sendTerminalPropertiesQuery(term.name, jsonRpcRequest)
           val update: Runnable = () => {
diff --git a/main/src/main/scala/sbt/nio/Settings.scala b/main/src/main/scala/sbt/nio/Settings.scala
index 7ca7bbd12..e08b9787a 100644
--- a/main/src/main/scala/sbt/nio/Settings.scala
+++ b/main/src/main/scala/sbt/nio/Settings.scala
@@ -245,7 +245,7 @@ private[sbt] object Settings {
     val created = createdBuilder.result()
     val modified = modifiedBuilder.result()
     if (created.isEmpty && deleted.isEmpty && modified.isEmpty) {
-      FileChanges.unmodified(unmodifiedBuilder.result)
+      FileChanges.unmodified(unmodifiedBuilder.result())
     } else {
       FileChanges(created, deleted, modified, unmodified)
     }
diff --git a/protocol/src/main/scala/sbt/protocol/ServerSession.scala b/protocol/src/main/scala/sbt/protocol/ServerSession.scala
index 8c6abe2b8..d451485b7 100644
--- a/protocol/src/main/scala/sbt/protocol/ServerSession.scala
+++ b/protocol/src/main/scala/sbt/protocol/ServerSession.scala
@@ -192,15 +192,15 @@ object ServerSession {
     val deadline = duration.fromNow
     var nextLog = PortfileLogInterval.fromNow
 
-    while (portfileIsEmpty() && !deadline.isOverdue && isAlive) {
-      if (nextLog.isOverdue) {
+    while (portfileIsEmpty() && !deadline.isOverdue() && isAlive) {
+      if (nextLog.isOverdue()) {
         log("Still waiting for sbt ...")
         nextLog = PortfileLogInterval.fromNow
       }
       Thread.sleep(10)
     }
 
-    if (deadline.isOverdue)
+    if (deadline.isOverdue())
       throw new TimeoutException(
         s"${portfile.getAbsolutePath} was not created within $duration"
       )
diff --git a/protocol/src/main/scala/sbt/protocol/ServerSessionImpl.scala b/protocol/src/main/scala/sbt/protocol/ServerSessionImpl.scala
index 830925608..12a1baf8d 100644
--- a/protocol/src/main/scala/sbt/protocol/ServerSessionImpl.scala
+++ b/protocol/src/main/scala/sbt/protocol/ServerSessionImpl.scala
@@ -256,7 +256,7 @@ private[sbt] class ServerSessionImpl(
           f(msg) match {
             case Some(result) => result
             case None =>
-              if (deadline.isOverdue)
+              if (deadline.isOverdue())
                 throw new TimeoutException(s"Timeout waiting for response after $duration")
               else impl()
           }
@@ -324,7 +324,7 @@ private[sbt] class ServerSessionImpl(
   override def shutdown(isAlive: => Boolean, destroy: () => Unit): Try[Unit] = {
     def waitForExit(isAlive: => Boolean, timeout: FiniteDuration): Unit = {
       val deadline = timeout.fromNow
-      while (!deadline.isOverdue && isAlive) Thread.sleep(10)
+      while (!deadline.isOverdue() && isAlive) Thread.sleep(10)
     }
 
     val result = for {
diff --git a/scripted-sbt/src/main/scala/sbt/scriptedtest/SbtHandler.scala b/scripted-sbt/src/main/scala/sbt/scriptedtest/SbtHandler.scala
index d8c145399..0a55cd8fd 100644
--- a/scripted-sbt/src/main/scala/sbt/scriptedtest/SbtHandler.scala
+++ b/scripted-sbt/src/main/scala/sbt/scriptedtest/SbtHandler.scala
@@ -67,7 +67,7 @@ final class SbtHandler(remoteSbtCreator: RemoteSbtCreator) extends StatementHand
       } catch {
         case _: IOException => process.destroy()
       } finally {
-        if (process.isAlive) process.destroy()
+        if (process.isAlive()) process.destroy()
         RunningProcesses.remove(process)
       }
   }
diff --git a/server-test/src/test/scala/testpkg/AbstractServerTest.scala b/server-test/src/test/scala/testpkg/AbstractServerTest.scala
index 64451579e..ca66b95b1 100644
--- a/server-test/src/test/scala/testpkg/AbstractServerTest.scala
+++ b/server-test/src/test/scala/testpkg/AbstractServerTest.scala
@@ -28,7 +28,7 @@ final class SbtServer(
     private val process: scala.sys.process.Process
 ) {
   def close(): Unit =
-    session.shutdown(process.isAlive, () => process.destroy()).get
+    session.shutdown(process.isAlive(), () => process.destroy()).get
 }
 
 trait AbstractServerTest extends AnyFunSuite with BeforeAndAfterAll {
@@ -80,7 +80,7 @@ trait AbstractServerTest extends AnyFunSuite with BeforeAndAfterAll {
     )
 
     val portfile = buildDir / "project" / "target" / "active.json"
-    ServerSession.waitForPortfile(portfile, process.isAlive)
+    ServerSession.waitForPortfile(portfile, process.isAlive())
 
     val session = ServerSession.connect(portfile)
     session.initialize(10.seconds, subscribeToAllForTest)
diff --git a/tasks-standard/src/test/scala/Test.scala b/tasks-standard/src/test/scala/Test.scala
index b4f2fffca..ca0c74c01 100644
--- a/tasks-standard/src/test/scala/Test.scala
+++ b/tasks-standard/src/test/scala/Test.scala
@@ -45,7 +45,7 @@ object Test extends std.TaskExtra:
   lazy val d3 = t3(a, b, c).flatMapR(f3)
 
   def d4(i: Int): Task[Int] = nop flatMap { _ =>
-    val x = math.random; if (x < 0.01) task(i); else d4(i + 1)
+    val x = math.random(); if (x < 0.01) task(i); else d4(i + 1)
   }
 
   def go(): Unit = {