diff --git a/build.gradle.kts b/build.gradle.kts
index 3ea7e5c..e561ef7 100644
--- a/build.gradle.kts
+++ b/build.gradle.kts
@@ -1,5 +1,5 @@
 plugins {
-    kotlin("jvm") version "2.0.0"
+    kotlin("jvm") version "2.2.21"
     id("io.github.gradle-nexus.publish-plugin") version "1.1.0"
 }
 
diff --git a/core/build.gradle.kts b/core/build.gradle.kts
index 43aadfe..386b229 100644
--- a/core/build.gradle.kts
+++ b/core/build.gradle.kts
@@ -1,10 +1,11 @@
 import com.vanniktech.maven.publish.JavadocJar
 import com.vanniktech.maven.publish.KotlinJvm
+import org.jetbrains.kotlin.gradle.dsl.JvmTarget
 import org.jetbrains.kotlin.gradle.tasks.KotlinCompile
 
 plugins {
     kotlin("jvm")
-    kotlin("plugin.serialization") version "2.0.0"
+    kotlin("plugin.serialization") version "2.2.21"
     id("com.vanniktech.maven.publish") version "0.34.0"
     id("org.jlleitschuh.gradle.ktlint") version "12.1.1"
     id("org.jetbrains.dokka") version "1.9.20"
@@ -20,7 +21,11 @@ java {
 }
 
 tasks {
-    withType<KotlinCompile> { kotlinOptions { jvmTarget = "17" } }
+    withType<KotlinCompile> {
+        compilerOptions {
+            jvmTarget.set(JvmTarget.JVM_17)
+        }
+    }
 }
 
 // Defined in gradle.properties
diff --git a/core/src/main/kotlin/cohort/CohortApi.kt b/core/src/main/kotlin/cohort/CohortApi.kt
index 311296d..8b03168 100644
--- a/core/src/main/kotlin/cohort/CohortApi.kt
+++ b/core/src/main/kotlin/cohort/CohortApi.kt
@@ -16,7 +16,6 @@ import io.ktor.client.request.headers
 import io.ktor.client.request.parameter
 import io.ktor.client.statement.bodyAsChannel
 import io.ktor.http.HttpStatusCode
-import io.ktor.util.toByteArray
 import io.ktor.utils.io.jvm.javaio.toInputStream
 import kotlinx.serialization.Serializable
 import okio.buffer
diff --git a/core/src/test/kotlin/project/ProjectApiTest.kt b/core/src/test/kotlin/project/ProjectApiTest.kt
index a9653df..c022727 100644
--- a/core/src/test/kotlin/project/ProjectApiTest.kt
+++ b/core/src/test/kotlin/project/ProjectApiTest.kt
@@ -3,6 +3,7 @@ package project
 import com.amplitude.project.DeploymentsResponse
 import com.amplitude.project.ProjectApiV1
 import com.amplitude.util.json
+import com.sun.net.httpserver.HttpServer
 import io.ktor.client.engine.mock.MockEngine
 import io.ktor.client.engine.mock.respond
 import io.ktor.http.HttpMethod
@@ -13,6 +14,7 @@ import kotlinx.serialization.encodeToString
 import org.junit.Test
 import test.deployment
 import test.toSerialDeployment
+import java.net.InetSocketAddress
 import kotlin.test.assertEquals
 
 class ProjectApiTest {
@@ -68,4 +70,28 @@ class ProjectApiTest {
             assertEquals("/api/1/deployments", request.url.encodedPath)
             assertEquals("Bearer $managementKey", request.headers["Authorization"])
         }
+
+    @Test
+    fun `get deployments over okhttp engine with coroutines 1_11`(): Unit =
+        runBlocking {
+            val expected = listOf(deployment("okhttp"))
+            val responseBody =
+                json.encodeToString(
+                    DeploymentsResponse(expected.map { it.toSerialDeployment() }),
+                ).toByteArray()
+            val server = HttpServer.create(InetSocketAddress("127.0.0.1", 0), 0)
+            server.createContext("/api/1/deployments") { exchange ->
+                exchange.responseHeaders.add("Content-Type", "application/json")
+                exchange.sendResponseHeaders(200, responseBody.size.toLong())
+                exchange.responseBody.use { it.write(responseBody) }
+            }
+            server.start()
+
+            try {
+                val api = ProjectApiV1("http://127.0.0.1:${server.address.port}/", managementKey)
+                assertEquals(expected, api.getDeployments())
+            } finally {
+                server.stop(0)
+            }
+        }
 }
diff --git a/gradle.properties b/gradle.properties
index 28aeefc..c1e4b3d 100644
--- a/gradle.properties
+++ b/gradle.properties
@@ -1,9 +1,9 @@
 # kotlin
 kotlin.code.style=official
-ktorVersion=2.3.12
-kotlinVersion=2.0.0
-coroutinesVersion=1.9.0-RC
-serializationVersion=1.7.1
+ktorVersion=3.3.3
+kotlinVersion=2.2.21
+coroutinesVersion=1.11.0
+serializationVersion=1.9.0
 
 # logging & metrics
 logbackVersion=1.4.6
diff --git a/gradle/wrapper/gradle-wrapper.jar b/gradle/wrapper/gradle-wrapper.jar
index 943f0cb..a4b76b9 100644
Binary files a/gradle/wrapper/gradle-wrapper.jar and b/gradle/wrapper/gradle-wrapper.jar differ
diff --git a/gradle/wrapper/gradle-wrapper.properties b/gradle/wrapper/gradle-wrapper.properties
index 3499ded..e2847c8 100644
--- a/gradle/wrapper/gradle-wrapper.properties
+++ b/gradle/wrapper/gradle-wrapper.properties
@@ -1,6 +1,7 @@
 distributionBase=GRADLE_USER_HOME
 distributionPath=wrapper/dists
-distributionUrl=https\://services.gradle.org/distributions/gradle-8.5-bin.zip
+distributionUrl=https\://services.gradle.org/distributions/gradle-8.11.1-bin.zip
 networkTimeout=10000
+validateDistributionUrl=true
 zipStoreBase=GRADLE_USER_HOME
 zipStorePath=wrapper/dists
diff --git a/gradlew b/gradlew
index 65dcd68..f5feea6 100755
--- a/gradlew
+++ b/gradlew
@@ -15,6 +15,8 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 #
+# SPDX-License-Identifier: Apache-2.0
+#
 
 ##############################################################################
 #
@@ -55,7 +57,7 @@
 #       Darwin, MinGW, and NonStop.
 #
 #   (3) This script is generated from the Groovy template
-#       https://github.com/gradle/gradle/blob/HEAD/subprojects/plugins/src/main/resources/org/gradle/api/internal/plugins/unixStartScript.txt
+#       https://github.com/gradle/gradle/blob/HEAD/platforms/jvm/plugins-application/src/main/resources/org/gradle/api/internal/plugins/unixStartScript.txt
 #       within the Gradle project.
 #
 #       You can find Gradle at https://github.com/gradle/gradle/.
@@ -83,10 +85,9 @@ done
 # This is normally unused
 # shellcheck disable=SC2034
 APP_BASE_NAME=${0##*/}
-APP_HOME=$( cd "${APP_HOME:-./}" && pwd -P ) || exit
-
-# Add default JVM options here. You can also use JAVA_OPTS and GRADLE_OPTS to pass JVM options to this script.
-DEFAULT_JVM_OPTS='"-Xmx64m" "-Xms64m"'
+# Discard cd standard output in case $CDPATH is set (https://github.com/gradle/gradle/issues/25036)
+APP_HOME=$( cd -P "${APP_HOME:-./}" > /dev/null && printf '%s
+' "$PWD" ) || exit
 
 # Use the maximum available, or set MAX_FD != -1 to use that value.
 MAX_FD=maximum
@@ -133,10 +134,13 @@ location of your Java installation."
     fi
 else
     JAVACMD=java
-    which java >/dev/null 2>&1 || die "ERROR: JAVA_HOME is not set and no 'java' command could be found in your PATH.
+    if ! command -v java >/dev/null 2>&1
+    then
+        die "ERROR: JAVA_HOME is not set and no 'java' command could be found in your PATH.
 
 Please set the JAVA_HOME variable in your environment to match the
 location of your Java installation."
+    fi
 fi
 
 # Increase the maximum file descriptors if we can.
@@ -144,7 +148,7 @@ if ! "$cygwin" && ! "$darwin" && ! "$nonstop" ; then
     case $MAX_FD in #(
       max*)
         # In POSIX sh, ulimit -H is undefined. That's why the result is checked to see if it worked.
-        # shellcheck disable=SC3045 
+        # shellcheck disable=SC2039,SC3045
         MAX_FD=$( ulimit -H -n ) ||
             warn "Could not query maximum file descriptor limit"
     esac
@@ -152,7 +156,7 @@ if ! "$cygwin" && ! "$darwin" && ! "$nonstop" ; then
       '' | soft) :;; #(
       *)
         # In POSIX sh, ulimit -n is undefined. That's why the result is checked to see if it worked.
-        # shellcheck disable=SC3045 
+        # shellcheck disable=SC2039,SC3045
         ulimit -n "$MAX_FD" ||
             warn "Could not set maximum file descriptor limit to $MAX_FD"
     esac
@@ -197,11 +201,15 @@ if "$cygwin" || "$msys" ; then
     done
 fi
 
-# Collect all arguments for the java command;
-#   * $DEFAULT_JVM_OPTS, $JAVA_OPTS, and $GRADLE_OPTS can contain fragments of
-#     shell script including quotes and variable substitutions, so put them in
-#     double quotes to make sure that they get re-expanded; and
-#   * put everything else in single quotes, so that it's not re-expanded.
+
+# Add default JVM options here. You can also use JAVA_OPTS and GRADLE_OPTS to pass JVM options to this script.
+DEFAULT_JVM_OPTS='"-Xmx64m" "-Xms64m"'
+
+# Collect all arguments for the java command:
+#   * DEFAULT_JVM_OPTS, JAVA_OPTS, JAVA_OPTS, and optsEnvironmentVar are not allowed to contain shell fragments,
+#     and any embedded shellness will be escaped.
+#   * For example: A user cannot expect ${Hostname} to be expanded, as it is an environment variable and will be
+#     treated as '${Hostname}' itself on the command line.
 
 set -- \
         "-Dorg.gradle.appname=$APP_BASE_NAME" \
diff --git a/gradlew.bat b/gradlew.bat
index 6689b85..9b42019 100644
--- a/gradlew.bat
+++ b/gradlew.bat
@@ -13,6 +13,8 @@
 @rem See the License for the specific language governing permissions and
 @rem limitations under the License.
 @rem
+@rem SPDX-License-Identifier: Apache-2.0
+@rem
 
 @if "%DEBUG%"=="" @echo off
 @rem ##########################################################################
@@ -43,11 +45,11 @@ set JAVA_EXE=java.exe
 %JAVA_EXE% -version >NUL 2>&1
 if %ERRORLEVEL% equ 0 goto execute
 
-echo.
-echo ERROR: JAVA_HOME is not set and no 'java' command could be found in your PATH.
-echo.
-echo Please set the JAVA_HOME variable in your environment to match the
-echo location of your Java installation.
+echo. 1>&2
+echo ERROR: JAVA_HOME is not set and no 'java' command could be found in your PATH. 1>&2
+echo. 1>&2
+echo Please set the JAVA_HOME variable in your environment to match the 1>&2
+echo location of your Java installation. 1>&2
 
 goto fail
 
@@ -57,11 +59,11 @@ set JAVA_EXE=%JAVA_HOME%/bin/java.exe
 
 if exist "%JAVA_EXE%" goto execute
 
-echo.
-echo ERROR: JAVA_HOME is set to an invalid directory: %JAVA_HOME%
-echo.
-echo Please set the JAVA_HOME variable in your environment to match the
-echo location of your Java installation.
+echo. 1>&2
+echo ERROR: JAVA_HOME is set to an invalid directory: %JAVA_HOME% 1>&2
+echo. 1>&2
+echo Please set the JAVA_HOME variable in your environment to match the 1>&2
+echo location of your Java installation. 1>&2
 
 goto fail
 
diff --git a/service/build.gradle.kts b/service/build.gradle.kts
index dbfb997..ef92394 100644
--- a/service/build.gradle.kts
+++ b/service/build.gradle.kts
@@ -1,10 +1,11 @@
+import org.jetbrains.kotlin.gradle.dsl.JvmTarget
 import org.jetbrains.kotlin.gradle.tasks.KotlinCompile
 
 plugins {
     application
-    id("io.ktor.plugin") version "2.3.4"
-    kotlin("jvm") version "2.0.0"
-    kotlin("plugin.serialization") version "2.0.0"
+    id("io.ktor.plugin") version "3.3.3"
+    kotlin("jvm") version "2.2.21"
+    kotlin("plugin.serialization") version "2.2.21"
     id("org.jlleitschuh.gradle.ktlint") version "12.1.1"
 }
 
@@ -20,7 +21,11 @@ java {
 }
 
 tasks {
-    withType<KotlinCompile> { kotlinOptions { jvmTarget = "17" } }
+    withType<KotlinCompile> {
+        compilerOptions {
+            jvmTarget.set(JvmTarget.JVM_17)
+        }
+    }
 }
 
 // Defined in gradle.properties
@@ -44,6 +49,6 @@ dependencies {
     implementation("io.ktor:ktor-client-okhttp:$ktorVersion")
     implementation("io.micrometer:micrometer-registry-prometheus:$prometheusVersion")
     implementation("ch.qos.logback:logback-classic:$logbackVersion")
-    testImplementation("io.ktor:ktor-server-tests-jvm:$ktorVersion")
+    testImplementation("io.ktor:ktor-server-test-host-jvm:$ktorVersion")
     testImplementation("org.jetbrains.kotlin:kotlin-test-junit:$kotlinVersion")
 }
diff --git a/service/src/main/kotlin/Server.kt b/service/src/main/kotlin/Server.kt
index 200a9c0..4b9838b 100644
--- a/service/src/main/kotlin/Server.kt
+++ b/service/src/main/kotlin/Server.kt
@@ -19,6 +19,7 @@ import io.ktor.server.engine.embeddedServer
 import io.ktor.server.netty.Netty
 import io.ktor.server.plugins.contentnegotiation.ContentNegotiation
 import io.ktor.server.request.ApplicationRequest
+import io.ktor.server.request.receiveText
 import io.ktor.server.request.uri
 import io.ktor.server.response.respond
 import io.ktor.server.response.respondBytes
@@ -26,7 +27,6 @@ import io.ktor.server.routing.get
 import io.ktor.server.routing.post
 import io.ktor.server.routing.routing
 import io.ktor.util.decodeBase64String
-import io.ktor.util.toByteArray
 import io.micrometer.prometheus.PrometheusConfig
 import io.micrometer.prometheus.PrometheusMeterRegistry
 import kotlinx.coroutines.runBlocking
@@ -121,7 +121,7 @@ fun Application.proxyServer(evaluationProxy: EvaluationProxy) {
     }
     install(
         createApplicationPlugin("shutdown") {
-            val plugin = ShutDownUrl("/shutdown") { 0 }
+            val plugin = ShutDownUrl("/shutdown", exitCode = { 0 })
             onCall { call ->
                 if (call.request.uri == plugin.url) {
                     evaluationProxy.shutdown()
@@ -314,8 +314,9 @@ private fun ApplicationRequest.getUserFromHeader(): Map<String, Any?> {
 /**
  * Get the user from the body. Used for SDK/REST POST requests.
  */
-private suspend fun ApplicationRequest.getUserFromBody(): Map<String, Any?> {
-    val userJson = this.receiveChannel().toByteArray().toString(Charsets.UTF_8)
+@VisibleForTesting
+internal suspend fun ApplicationRequest.getUserFromBody(): Map<String, Any?> {
+    val userJson = call.receiveText()
     return json.decodeFromString<JsonObject>(userJson).toAnyMap()
 }
 
diff --git a/service/src/main/kotlin/plugins/Monitoring.kt b/service/src/main/kotlin/plugins/Monitoring.kt
index c94e43b..5ed7e71 100644
--- a/service/src/main/kotlin/plugins/Monitoring.kt
+++ b/service/src/main/kotlin/plugins/Monitoring.kt
@@ -36,7 +36,7 @@ import io.ktor.server.application.Application
 import io.ktor.server.application.call
 import io.ktor.server.application.install
 import io.ktor.server.metrics.micrometer.MicrometerMetrics
-import io.ktor.server.plugins.callloging.CallLogging
+import io.ktor.server.plugins.calllogging.CallLogging
 import io.ktor.server.request.path
 import io.ktor.server.routing.get
 import io.micrometer.prometheus.PrometheusMeterRegistry
diff --git a/service/src/test/kotlin/ServerTest.kt b/service/src/test/kotlin/ServerTest.kt
index 918eb7a..9105daa 100644
--- a/service/src/test/kotlin/ServerTest.kt
+++ b/service/src/test/kotlin/ServerTest.kt
@@ -1,5 +1,14 @@
 import com.amplitude.getApiAndSecretKey
+import com.amplitude.getUserFromBody
+import io.ktor.client.request.post
+import io.ktor.client.request.setBody
+import io.ktor.client.statement.bodyAsText
 import io.ktor.http.Headers
+import io.ktor.server.application.call
+import io.ktor.server.response.respondText
+import io.ktor.server.routing.post
+import io.ktor.server.routing.routing
+import io.ktor.server.testing.testApplication
 import io.ktor.util.encodeBase64
 import kotlin.test.Test
 import kotlin.test.assertEquals
@@ -18,4 +27,23 @@ class ServerTest {
         assertEquals(apiKey, result.first)
         assertEquals(secretKey, result.second)
     }
+
+    @Test
+    fun `test get user from body`() =
+        testApplication {
+            application {
+                routing {
+                    post("/") {
+                        val user = call.request.getUserFromBody()
+                        call.respondText(user["user_id"].toString())
+                    }
+                }
+            }
+
+            val response =
+                client.post("/") {
+                    setBody("""{"user_id":"test-user"}""")
+                }
+            assertEquals("test-user", response.bodyAsText())
+        }
 }