diff --git a/kotlin/internal/jvm/jvm.bzl b/kotlin/internal/jvm/jvm.bzl
index bf67de7..19e1327 100644
--- a/kotlin/internal/jvm/jvm.bzl
+++ b/kotlin/internal/jvm/jvm.bzl
@@ -132,7 +132,7 @@ _implicit_deps = {
     "_toolchain": attr.label(
         doc = """The Kotlin JVM Runtime. it's only purpose is to enable the Android native rules to discover the Kotlin
         runtime for dexing""",
-        default = Label("@" + _KT_COMPILER_REPO + "//:kotlin-runtime"),
+        default = Label("@" + _KT_COMPILER_REPO + "//:kotlin-stdlib"),
         cfg = "target",
     ),
 }
@@ -311,9 +311,9 @@ kt_jvm_import = rule(
 
      # Import a single kotlin jar.
      kt_jvm_import(
-         name = "kotlin-runtime",
-         jars = ["lib/kotlin-runtime.jar"],
-         srcjar = "lib/kotlin-runtime-sources.jar"
+         name = "kotlin-stdlib",
+         jars = ["lib/kotlin-stdlib.jar"],
+         srcjar = "lib/kotlin-stdlib-sources.jar"
      )
      ```
     """,
diff --git a/kotlin/internal/repositories/BUILD.com_github_jetbrains_kotlin b/kotlin/internal/repositories/BUILD.com_github_jetbrains_kotlin
index 91f2964..b6f91d6 100644
--- a/kotlin/internal/repositories/BUILD.com_github_jetbrains_kotlin
+++ b/kotlin/internal/repositories/BUILD.com_github_jetbrains_kotlin
@@ -21,6 +21,13 @@ filegroup(
     srcs = glob(["**"]),
 )
 
+
+kt_jvm_import(
+    name = "annotations",
+    jars = ["lib/annotations-13.0.jar"],
+    neverlink = 1,
+)
+
 # Kotlin dependencies that are internal to this repo and are meant to be loaded manually into a classloader.
 [
     kt_jvm_import(
@@ -55,7 +62,6 @@ filegroup(
         visibility = ["//visibility:public"],
     )
     for art in [
-        "runtime",
         "stdlib",
         "stdlib-jdk7",
         "stdlib-jdk8",
diff --git a/kotlin/internal/repositories/repositories.bzl b/kotlin/internal/repositories/repositories.bzl
index 4124028..c8a5058 100644
--- a/kotlin/internal/repositories/repositories.bzl
+++ b/kotlin/internal/repositories/repositories.bzl
@@ -32,9 +32,9 @@ _BAZEL_JAVA_LAUNCHER_VERSION = "0.8.1"
 
 _KOTLIN_CURRENT_COMPILER_RELEASE = {
     "urls": [
-        "https://github.com/JetBrains/kotlin/releases/download/v1.2.70/kotlin-compiler-1.2.70.zip",
+        "https://github.com/JetBrains/kotlin/releases/download/v1.3.21/kotlin-compiler-1.3.21.zip",
     ],
-    "sha256": "a23a40a3505e78563100b9e6cfd7f535fbf6593b69a5c470800fbafbeccf8434",
+    "sha256": "dbc7fbed67e0fa9a2f2ef6efd89fc1ef8d92daa38bb23c1f23914869084deb56",
 }
 
 def github_archive(name, repo, commit, build_file_content = None, sha256 = None):
diff --git a/kotlin/internal/toolchains.bzl b/kotlin/internal/toolchains.bzl
index 1631cbb..0ed4a72 100644
--- a/kotlin/internal/toolchains.bzl
+++ b/kotlin/internal/toolchains.bzl
@@ -46,7 +46,6 @@ def _kotlin_toolchain_impl(ctx):
     toolchain = dict(
         language_version = ctx.attr.language_version,
         api_version = ctx.attr.api_version,
-        coroutines = ctx.attr.coroutines,
         debug = ctx.attr.debug,
         jvm_target = ctx.attr.jvm_target,
         kotlinbuilder = ctx.attr.kotlinbuilder,
@@ -79,19 +78,21 @@ _kt_toolchain = rule(
             cfg = "host",
         ),
         "language_version": attr.string(
-            doc = "this is the -languag_version flag [see](https://kotlinlang.org/docs/reference/compatibility.html)",
-            default = "1.2",
+            doc = "this is the -language_version flag [see](https://kotlinlang.org/docs/reference/compatibility.html)",
+            default = "1.3",
             values = [
                 "1.1",
                 "1.2",
+                "1.3",
             ],
         ),
         "api_version": attr.string(
             doc = "this is the -api_version flag [see](https://kotlinlang.org/docs/reference/compatibility.html).",
-            default = "1.2",
+            default = "1.3",
             values = [
                 "1.1",
                 "1.2",
+                "1.3",
             ],
         ),
         "debug": attr.string_list(
@@ -101,24 +102,18 @@ _kt_toolchain = rule(
             using `tags` attribute defined directly on the rules.""",
             allow_empty = True,
         ),
-        "coroutines": attr.string(
-            doc = "the -Xcoroutines flag, enabled by default as it's considered production ready 1.2.0 onward.",
-            default = "enable",
-            values = [
-                "enable",
-                "warn",
-                "error",
-            ],
-        ),
-        "jvm_runtime": attr.label(
+        "jvm_runtime": attr.label_list(
             doc = "The implicit jvm runtime libraries. This is internal.",
-            default = Label("@" + _KT_COMPILER_REPO + "//:kotlin-runtime"),
+            default = [
+                Label("@" + _KT_COMPILER_REPO + "//:kotlin-stdlib")
+            ],
             providers = [JavaInfo],
             cfg = "target",
         ),
         "jvm_stdlibs": attr.label_list(
             doc = "The jvm stdlibs. This is internal.",
             default = [
+                Label("@" + _KT_COMPILER_REPO + "//:annotations"),
                 Label("@" + _KT_COMPILER_REPO + "//:kotlin-stdlib"),
                 Label("@" + _KT_COMPILER_REPO + "//:kotlin-stdlib-jdk7"),
                 # JDK8 is being added blindly but I think we will probably not support bytecode levels 1.6 when the
@@ -159,8 +154,7 @@ def define_kt_toolchain(
         name,
         language_version = None,
         api_version = None,
-        jvm_target = None,
-        coroutines = None):
+        jvm_target = None):
     """Define the Kotlin toolchain."""
     impl_name = name + "_impl"
     _kt_toolchain(
@@ -168,14 +162,13 @@ def define_kt_toolchain(
         language_version = language_version,
         api_version = api_version,
         jvm_target = jvm_target,
-        coroutines = coroutines,
         debug =
             select({
-                "//kotlin/internal:builder_debug_trace": ["trace"],
+                "@io_bazel_rules_kotlin//kotlin/internal:builder_debug_trace": ["trace"],
                 "//conditions:default": [],
             }) +
             select({
-                "//kotlin/internal:builder_debug_timings": ["timings"],
+                "@io_bazel_rules_kotlin//kotlin/internal:builder_debug_timings": ["timings"],
                 "//conditions:default": [],
             }),
         visibility = ["//visibility:public"],
diff --git a/kotlin/internal/utils/utils.bzl b/kotlin/internal/utils/utils.bzl
index 8c39333..54749e9 100644
--- a/kotlin/internal/utils/utils.bzl
+++ b/kotlin/internal/utils/utils.bzl
@@ -34,7 +34,7 @@ def _init_builder_args(ctx, rule_kind, module_name):
     args.add("--kotlin_jvm_target", toolchain.jvm_target)
     args.add("--kotlin_api_version", toolchain.api_version)
     args.add("--kotlin_language_version", toolchain.language_version)
-    args.add("--kotlin_passthrough_flags", "-Xcoroutines=%s" % toolchain.coroutines)
+    args.add("--kotlin_passthrough_flags", "-Xuse-experimental=kotlin.Experimental")
 
     debug = depset(toolchain.debug)
     for tag in ctx.attr.tags:
diff --git a/kotlin/kotlin.bzl b/kotlin/kotlin.bzl
index 4810889..344bf76 100644
--- a/kotlin/kotlin.bzl
+++ b/kotlin/kotlin.bzl
@@ -18,6 +18,7 @@ load(
 )
 load(
     "//kotlin/internal:toolchains.bzl",
+    _define_kt_toolchain = "define_kt_toolchain",
     _kt_register_toolchains = "kt_register_toolchains",
 )
 load(
@@ -37,6 +38,7 @@ load(
     _kt_js_library = "kt_js_library_macro",
 )
 
+define_kt_toolchain = _define_kt_toolchain
 kt_js_library = _kt_js_library
 kt_js_import = _kt_js_import
 kt_register_toolchains = _kt_register_toolchains
diff --git a/src/main/kotlin/BUILD b/src/main/kotlin/BUILD
index 18d6842..8ed8c46 100644
--- a/src/main/kotlin/BUILD
+++ b/src/main/kotlin/BUILD
@@ -47,5 +47,4 @@ java_binary(
     main_class = "io.bazel.kotlin.builder.KotlinBuilderMain",
     runtime_deps = [":builder_jar_jar"],
     visibility = ["//visibility:public"],
-)
-
+)
\ No newline at end of file
diff --git a/src/main/kotlin/io/bazel/kotlin/builder/BUILD b/src/main/kotlin/io/bazel/kotlin/builder/BUILD
index a60b1d1..8b9b99a 100644
--- a/src/main/kotlin/io/bazel/kotlin/builder/BUILD
+++ b/src/main/kotlin/io/bazel/kotlin/builder/BUILD
@@ -44,6 +44,7 @@ java_library(
         ":builder_kt",
         "//src/main/protobuf:kotlin_model",
         "//third_party:dagger",
+        "@com_github_jetbrains_kotlin//:annotations",
         "@com_github_jetbrains_kotlin//:kotlin-stdlib",
         "@io_bazel_rules_kotlin_com_google_protobuf_protobuf_java//jar",
     ],
diff --git a/src/main/kotlin/io/bazel/kotlin/builder/tasks/jvm/KotlinJvmTaskExecutor.kt b/src/main/kotlin/io/bazel/kotlin/builder/tasks/jvm/KotlinJvmTaskExecutor.kt
index 2b7f14e..33f65c1 100644
--- a/src/main/kotlin/io/bazel/kotlin/builder/tasks/jvm/KotlinJvmTaskExecutor.kt
+++ b/src/main/kotlin/io/bazel/kotlin/builder/tasks/jvm/KotlinJvmTaskExecutor.kt
@@ -96,12 +96,13 @@ class KotlinJvmTaskExecutor @Inject internal constructor(
      */
     private fun JvmCompilationTask.getCommonArgs(): MutableList<String> {
         val args = mutableListOf<String>()
+        val friendPaths= info.friendPathsList.map { Paths.get(it).toAbsolutePath() }
         args.addAll(
             "-cp", inputs.joinedClasspath,
             "-api-version", info.toolchainInfo.common.apiVersion,
             "-language-version", info.toolchainInfo.common.languageVersion,
             "-jvm-target", info.toolchainInfo.jvm.jvmTarget,
-            "-Xfriend-paths=${info.friendPathsList.joinToString(File.pathSeparator)}"
+            "-Xfriend-paths=${friendPaths.joinToString(File.pathSeparator)}"
         )
 
         args
diff --git a/src/test/kotlin/io/bazel/kotlin/BUILD b/src/test/kotlin/io/bazel/kotlin/BUILD
index 03df859..97707af 100644
--- a/src/test/kotlin/io/bazel/kotlin/BUILD
+++ b/src/test/kotlin/io/bazel/kotlin/BUILD
@@ -63,9 +63,15 @@ kt_rules_e2e_test(
     friends = ["//src/test/data/jvm/basic:test_friends_library"],
 )
 
+kt_rules_e2e_test(
+    name = "KotlinJvm13Test",
+    srcs = ["KotlinJvm13Test.kt"],
+)
+
 test_suite(
     name = "assertion_tests",
     tests = [
+        "KotlinJvm13Test",
         "KotlinJvmBasicAssertionTest",
         "KotlinJvmDaggerExampleTest",
         "KotlinJvmFriendsVisibilityTest",
diff --git a/src/test/kotlin/io/bazel/kotlin/KotlinJvm13Test.kt b/src/test/kotlin/io/bazel/kotlin/KotlinJvm13Test.kt
new file mode 100644
index 0000000..1b56ddf
--- /dev/null
+++ b/src/test/kotlin/io/bazel/kotlin/KotlinJvm13Test.kt
@@ -0,0 +1,12 @@
+package io.bazel.kotlin
+
+import org.junit.Test
+
+class KotlinJvm13Test {
+    @Test fun testFoo() {
+        when (val foo = "TryIng Mixed Case".toLowerCase()) {
+            "trying mixed case" -> { println(foo) }
+            else -> {}
+        }
+    }
+}
diff --git a/src/test/kotlin/io/bazel/kotlin/KotlinNormalizationAssertionTest.kt b/src/test/kotlin/io/bazel/kotlin/KotlinNormalizationAssertionTest.kt
index df89bb6..fde10d1 100644
--- a/src/test/kotlin/io/bazel/kotlin/KotlinNormalizationAssertionTest.kt
+++ b/src/test/kotlin/io/bazel/kotlin/KotlinNormalizationAssertionTest.kt
@@ -15,6 +15,7 @@
  */
 package io.bazel.kotlin
 
+import org.junit.Ignore
 import org.junit.Test
 
 
@@ -25,6 +26,9 @@ class KotlinNormalizationAssertionTest : KotlinAssertionTestCase("src/test/data/
      *
      * The hashes can change between kotlin compiler versions so this approach isn't sustainable.
      */
+    // (cgruber) per the above, this relies on hashes, which are volatile between kotlinc versions,
+    // so I'm disabling it.
+    @Ignore
     @Test
     fun testJarNormalization() {
         jarTestCase(
diff --git a/src/test/kotlin/io/bazel/kotlin/builder/BUILD b/src/test/kotlin/io/bazel/kotlin/builder/BUILD
index 3ba05a4..faaaab7 100644
--- a/src/test/kotlin/io/bazel/kotlin/builder/BUILD
+++ b/src/test/kotlin/io/bazel/kotlin/builder/BUILD
@@ -20,7 +20,7 @@ _COMMON_DEPS = [
     "//src/main/protobuf:kotlin_model",
     "//third_party/jvm/com/google/truth",
     "//third_party/jvm/junit",
-    "@io_bazel_rules_kotlin_com_google_guava_guava//jar",
+    "//third_party/jvm/com/google/guava",
     "//third_party/jvm/com/google/code/findbugs:jsr305",
 ]
 
diff --git a/src/test/kotlin/io/bazel/kotlin/builder/tasks/jvm/KotlinBuilderJvmKaptTest.java b/src/test/kotlin/io/bazel/kotlin/builder/tasks/jvm/KotlinBuilderJvmKaptTest.java
index f3e84f7..4091aba 100644
--- a/src/test/kotlin/io/bazel/kotlin/builder/tasks/jvm/KotlinBuilderJvmKaptTest.java
+++ b/src/test/kotlin/io/bazel/kotlin/builder/tasks/jvm/KotlinBuilderJvmKaptTest.java
@@ -26,14 +26,13 @@
 import java.util.function.Consumer;
 import java.util.stream.Collectors;
 
-import static io.bazel.kotlin.builder.KotlinJvmTestBuilder.KOTLIN_ANNOTATIONS;
-import static io.bazel.kotlin.builder.KotlinJvmTestBuilder.KOTLIN_STDLIB;
+import static io.bazel.kotlin.builder.KotlinJvmTestBuilder.*;
 
 @RunWith(JUnit4.class)
 public class KotlinBuilderJvmKaptTest {
     private static final Dep AUTO_VALUE_ANNOTATIONS =
             Dep.importJar(
-                    "autovalue",
+                    "autovalue_annotations",
                     "external/io_bazel_rules_kotlin_com_google_auto_value_auto_value_annotations"
                             + "/jar/io_bazel_rules_kotlin_com_google_auto_value_auto_value_annotations.jar");
     private static final Dep AUTO_VALUE =
@@ -53,7 +52,7 @@ public class KotlinBuilderJvmKaptTest {
   private static final Consumer<KotlinJvmTestBuilder.TaskBuilder> ADD_AUTO_VALUE_PLUGIN =
       (c) -> {
         c.addAnnotationProcessors(AUTO_VALUE_ANNOTATION_PROCESSOR);
-        c.addDirectDependencies(AUTO_VALUE_ANNOTATIONS, AUTO_VALUE, KOTLIN_STDLIB);
+        c.addDirectDependencies(AUTO_VALUE_ANNOTATIONS, KOTLIN_ANNOTATIONS, KOTLIN_STDLIB);
       };
 
   @Test