diff --git a/kobalt/src/Build.kt b/kobalt/src/Build.kt
index 0d7e5890..870e5eca 100644
--- a/kobalt/src/Build.kt
+++ b/kobalt/src/Build.kt
@@ -111,7 +111,7 @@ val kobaltApp = kotlinProject(kobaltPluginApi, wrapper) {
 
     dependencies {
         // Used by the plugins
-        compile("org.jetbrains.kotlin:kotlin-compiler-embeddable:1.0.0-beta-3595",
+        compile("org.jetbrains.kotlin:kotlin-compiler-embeddable:1.0.0-beta-4584",
                 "org.jetbrains.dokka:dokka-fatjar:0.9.3")
 
         // Used by the main app
diff --git a/modules/kobalt-plugin-api/src/main/kotlin/com/beust/kobalt/maven/RepoFinder.kt b/modules/kobalt-plugin-api/src/main/kotlin/com/beust/kobalt/maven/RepoFinder.kt
index 365ca110..89e9e915 100644
--- a/modules/kobalt-plugin-api/src/main/kotlin/com/beust/kobalt/maven/RepoFinder.kt
+++ b/modules/kobalt-plugin-api/src/main/kotlin/com/beust/kobalt/maven/RepoFinder.kt
@@ -144,7 +144,7 @@ public class RepoFinder @Inject constructor(val executors: KobaltExecutors) {
     val XPATH = XPATH_FACTORY.newXPath();
 
     fun findCorrectVersionRelease(metadataPath: String, repoUrl: String): String? {
-        val XPATHS = arrayListOf(
+        val XPATHS = listOf(
                 XPATH.compile("/metadata/version"),
                 XPATH.compile("/metadata/versioning/latest"),
                 XPATH.compile("/metadata/versioning/release"))
diff --git a/modules/kobalt-plugin-api/src/main/kotlin/com/beust/kobalt/misc/KFiles.kt b/modules/kobalt-plugin-api/src/main/kotlin/com/beust/kobalt/misc/KFiles.kt
index a0909add..7eb68455 100644
--- a/modules/kobalt-plugin-api/src/main/kotlin/com/beust/kobalt/misc/KFiles.kt
+++ b/modules/kobalt-plugin-api/src/main/kotlin/com/beust/kobalt/misc/KFiles.kt
@@ -283,9 +283,8 @@ class KFiles {
             if (excludes.isEmpty()) {
                 return false
             } else {
-                val ex = arrayListOf<PathMatcher>()
-                excludes.forEach {
-                    ex.add(FileSystems.getDefault().getPathMatcher("glob:${it.spec}"))
+                val ex = excludes.map {
+                    FileSystems.getDefault().getPathMatcher("glob:${it.spec}")
                 }
                 ex.forEach {
                     if (it.matches(Paths.get(file))) {
diff --git a/modules/kobalt-plugin-api/src/main/kotlin/com/beust/kobalt/misc/RunCommand.kt b/modules/kobalt-plugin-api/src/main/kotlin/com/beust/kobalt/misc/RunCommand.kt
index 3576f0e4..e6669039 100644
--- a/modules/kobalt-plugin-api/src/main/kotlin/com/beust/kobalt/misc/RunCommand.kt
+++ b/modules/kobalt-plugin-api/src/main/kotlin/com/beust/kobalt/misc/RunCommand.kt
@@ -43,7 +43,7 @@ open class RunCommand(val command: String) {
             "\n  " + allArgs.joinToString(" "))
         val process = pb.start()
         pb.environment().let { pbEnv ->
-            env.forEach {
+            env.forEach {it ->
                 pbEnv.put(it.key, it.value)
             }
         }
diff --git a/src/main/kotlin/com/beust/kobalt/app/ParsedBuildFile.kt b/src/main/kotlin/com/beust/kobalt/app/ParsedBuildFile.kt
index f68745d8..d59ee2f3 100644
--- a/src/main/kotlin/com/beust/kobalt/app/ParsedBuildFile.kt
+++ b/src/main/kotlin/com/beust/kobalt/app/ParsedBuildFile.kt
@@ -15,7 +15,6 @@ import java.net.URL
 import java.nio.charset.Charset
 import java.nio.file.Paths
 import java.util.*
-import kotlin.text.Regex
 
 class ParsedBuildFile(val buildFile: BuildFile, val context: KobaltContext, val buildScriptUtil: BuildScriptUtil,
         val dependencyManager: DependencyManager, val files: KFiles) {
@@ -74,7 +73,7 @@ class ParsedBuildFile(val buildFile: BuildFile, val context: KobaltContext, val
              * val profile = true, otherwise return the same line
              */
             fun correctProfileLine(line: String) : String {
-                context.profiles.forEach {
+                (context.profiles as List<String>).forEach {
                     if (line.matches(Regex("[ \\t]*val[ \\t]+$it[ \\t]+=.*"))) {
                         with("val $it = true") {
                             profileLines.add(this)
diff --git a/src/main/kotlin/com/beust/kobalt/plugin/application/ApplicationPlugin.kt b/src/main/kotlin/com/beust/kobalt/plugin/application/ApplicationPlugin.kt
index 9664f75f..4bfcacc7 100644
--- a/src/main/kotlin/com/beust/kobalt/plugin/application/ApplicationPlugin.kt
+++ b/src/main/kotlin/com/beust/kobalt/plugin/application/ApplicationPlugin.kt
@@ -10,6 +10,7 @@ import com.beust.kobalt.maven.DependencyManager
 import com.beust.kobalt.misc.KobaltExecutors
 import com.beust.kobalt.misc.RunCommand
 import com.beust.kobalt.misc.warn
+import com.beust.kobalt.plugin.packaging.Jar
 import com.beust.kobalt.plugin.packaging.PackageConfig
 import com.beust.kobalt.plugin.packaging.PackagingPlugin
 import com.google.inject.Inject
@@ -65,7 +66,7 @@ class ApplicationPlugin @Inject constructor(val executors: KobaltExecutors,
 
     private fun isFatJar(packages: List<PackageConfig>, jarName: String): Boolean {
         packages.forEach { pc ->
-            pc.jars.forEach { jar ->
+            (pc.jars as List<Jar>).forEach { jar ->
                 if ((jar.name == null || jar.name == jarName) && jar.fatJar) {
                     return true
                 }
diff --git a/src/main/kotlin/com/beust/kobalt/plugin/kotlin/KotlinCompiler.kt b/src/main/kotlin/com/beust/kobalt/plugin/kotlin/KotlinCompiler.kt
index c6a373f9..4c09fa6c 100644
--- a/src/main/kotlin/com/beust/kobalt/plugin/kotlin/KotlinCompiler.kt
+++ b/src/main/kotlin/com/beust/kobalt/plugin/kotlin/KotlinCompiler.kt
@@ -33,7 +33,7 @@ class KotlinCompiler @Inject constructor(
         val executors: KobaltExecutors,
         val jvmCompiler: JvmCompiler) {
     companion object {
-        val KOTLIN_VERSION = "1.0.0-beta-3595"
+        val KOTLIN_VERSION = "1.0.0-beta-4584"
     }
 
     val compilerAction = object: ICompilerAction {
diff --git a/src/test/kotlin/com/beust/kobalt/internal/DynamicGraphTest.kt b/src/test/kotlin/com/beust/kobalt/internal/DynamicGraphTest.kt
index f0361288..eacb313d 100644
--- a/src/test/kotlin/com/beust/kobalt/internal/DynamicGraphTest.kt
+++ b/src/test/kotlin/com/beust/kobalt/internal/DynamicGraphTest.kt
@@ -64,7 +64,7 @@ public class DynamicGraphTest {
         val factory = createFactory(runNodes, { n -> n != 3 })
         val ex = DynamicGraphExecutor(g, factory)
         ex.run()
-        Thread.yield()
+        Thread.`yield`()
         Assert.assertTrue(! runNodes.contains(4))
         Assert.assertTrue(! runNodes.contains(10))
     }