diff --git a/build-logic/src/main/kotlin/live.kotlin-conventions.gradle.kts b/build-logic/src/main/kotlin/live.kotlin-conventions.gradle.kts
index b86ac3d8e..5852b1567 100644
--- a/build-logic/src/main/kotlin/live.kotlin-conventions.gradle.kts
+++ b/build-logic/src/main/kotlin/live.kotlin-conventions.gradle.kts
@@ -1,3 +1,5 @@
+import org.jetbrains.kotlin.gradle.dsl.JvmDefaultMode
+
 plugins {
     java
     kotlin("jvm")
@@ -21,8 +23,10 @@ kotlin {
     compilerOptions {
         allWarningsAsErrors = true
         compilerOptions {
-            freeCompilerArgs.add("-Xjvm-default=all")
+            jvmDefault = JvmDefaultMode.NO_COMPATIBILITY
             freeCompilerArgs.add("-Xcontext-parameters")
+            freeCompilerArgs.add("-Xreturn-value-checker=full")
+            progressiveMode = true
             optIn.addAll(listOf(
                 "kotlinx.serialization.ExperimentalSerializationApi",
                 "kotlin.time.ExperimentalTime",
diff --git a/build-logic/src/main/kotlin/org/icpclive/gradle/tasks/SchemaGeneratorTask.kt b/build-logic/src/main/kotlin/org/icpclive/gradle/tasks/SchemaGeneratorTask.kt
index e5cd07766..bcb3230b0 100644
--- a/build-logic/src/main/kotlin/org/icpclive/gradle/tasks/SchemaGeneratorTask.kt
+++ b/build-logic/src/main/kotlin/org/icpclive/gradle/tasks/SchemaGeneratorTask.kt
@@ -1,6 +1,5 @@
 package org.icpclive.gradle.tasks
 
-import gradle.kotlin.dsl.accessors._0efe46a4cec2e9e682da24afc1fcb716.sourceSets
 import kotlinx.serialization.*
 import kotlinx.serialization.json.*
 import kotlinx.serialization.modules.*
diff --git a/gradle/libs.versions.toml b/gradle/libs.versions.toml
index 512a2e45f..1446e6146 100644
--- a/gradle/libs.versions.toml
+++ b/gradle/libs.versions.toml
@@ -1,25 +1,25 @@
 [versions]
-ktor = "3.3.2"                     # https://ktor.io/
+ktor = "3.3.3"                     # https://ktor.io/
 datetime = "0.7.1"                 # https://github.com/Kotlin/kotlinx-datetime
 serialization = "1.9.0"            # https://github.com/Kotlin/kotlinx.serialization
-kotlin = "2.2.21"
-ksp = "2.3.3"                      # https://github.com/google/ksp
+kotlin = "2.3.0"
+ksp = "2.3.4"                      # https://github.com/google/ksp
 slf4j = "2.0.17"                   # https://www.slf4j.org/download.html
-logback = "1.5.21"                 # https://logback.qos.ch/download.html
+logback = "1.5.22"                 # https://logback.qos.ch/download.html
 node-plugin = "7.1.0"              # https://github.com/node-gradle/gradle-node-plugin
 coroutines = "1.10.2"              # https://github.com/Kotlin/kotlinx.coroutines/
-shadow-plugin = "9.2.2"            # https://github.com/GradleUp/shadow
+shadow-plugin = "9.3.0"            # https://github.com/GradleUp/shadow
 clikt = "5.0.3"                    # https://ajalt.github.io/clikt/
 immutable = "0.4.0"                # https://github.com/Kotlin/kotlinx.collections.immutable
-protobuf-plugin = "0.9.5"          # https://github.com/google/protobuf-gradle-plugin
-protobuf = "4.32.1"                # https://mvnrepository.com/artifact/com.google.protobuf/protobuf-kotlin
-grpc = "1.73.0"                    # https://mvnrepository.com/artifact/io.grpc/grpc-stub
-grpc-kotlin = "1.4.1"              # https://mvnrepository.com/artifact/io.grpc/grpc-kotlin-stub
+protobuf-plugin = "0.9.6"          # https://github.com/google/protobuf-gradle-plugin
+protobuf = "4.33.2"                # https://mvnrepository.com/artifact/com.google.protobuf/protobuf-kotlin
+grpc = "1.77.0"                    # https://mvnrepository.com/artifact/io.grpc/grpc-stub
+grpc-kotlin = "1.5.0"              # https://mvnrepository.com/artifact/io.grpc/grpc-kotlin-stub
 dokka = "2.1.0"                    # https://github.com/Kotlin/dokka
 kxs-ts-gen = "0.2.4"               # https://github.com/adamko-dev/kotlinx-serialization-typescript-generator
 apache-commons-csv = "1.14.1"      # https://commons.apache.org/proper/commons-csv/
 graphql = "8.8.1"                  # https://github.com/ExpediaGroup/graphql-kotlin/tree/master
-json-schema-validator = "0.5.2"    # https://github.com/OptimumCode/json-schema-validator
+json-schema-validator = "0.5.3"    # https://github.com/OptimumCode/json-schema-validator
 
 [libraries]
 
@@ -63,7 +63,8 @@ cli = { version.ref = "clikt", group = "com.github.ajalt.clikt", name = "clikt"
 
 grpc-netty = { version.ref = "grpc", group = "io.grpc", name = "grpc-netty" }
 grpc-protobuf = { version.ref = "grpc", group = "io.grpc", name = "grpc-protobuf" }
-grpc-stub = { version.ref = "grpc-kotlin", group = "io.grpc", name = "grpc-kotlin-stub" }
+grpc-stub = { version.ref = "grpc", group = "io.grpc", name = "grpc-stub" }
+grpc-kotlin-stub = { version.ref = "grpc-kotlin", group = "io.grpc", name = "grpc-kotlin-stub" }
 grpc-gen-java = { version.ref = "grpc", group = "io.grpc", name = "protoc-gen-grpc-java" }
 grpc-gen-kotlin = { version.ref = "grpc-kotlin", group = "io.grpc", name = "protoc-gen-grpc-kotlin" }
 
diff --git a/src/backend/src/main/kotlin/org/icpclive/admin/Routing.kt b/src/backend/src/main/kotlin/org/icpclive/admin/Routing.kt
index c81acd7c4..7dbfd3569 100644
--- a/src/backend/src/main/kotlin/org/icpclive/admin/Routing.kt
+++ b/src/backend/src/main/kotlin/org/icpclive/admin/Routing.kt
@@ -176,7 +176,7 @@ fun Route.configureAdminApiRouting() {
                 validate = {
                     try {
                         // check if parsable
-                        TuningRule.listFromString(it)
+                        val _ = TuningRule.listFromString(it)
                     } catch (e: SerializationException) {
                         throw ApiActionException("Failed to deserialize advanced.json: ${e.message}", e)
                     }
diff --git a/src/backend/src/main/kotlin/org/icpclive/controllers/LocatorWidgetController.kt b/src/backend/src/main/kotlin/org/icpclive/controllers/LocatorWidgetController.kt
index b0337e1f2..4404e5df7 100644
--- a/src/backend/src/main/kotlin/org/icpclive/controllers/LocatorWidgetController.kt
+++ b/src/backend/src/main/kotlin/org/icpclive/controllers/LocatorWidgetController.kt
@@ -14,7 +14,7 @@ class LocatorWidgetController(manager: Manager<in TeamLocatorWidget>) :
     override suspend fun checkSettings(settings: ExternalTeamLocatorSettings) {
         val info = DataBus.currentContestInfo()
         settings.circles.forEach {
-            it.getTeam(info) ?: throw ApiActionException("No team for circle $it")
+            val _ = it.getTeam(info) ?: throw ApiActionException("No team for circle $it")
         }
     }
 
diff --git a/src/backend/src/main/kotlin/org/icpclive/controllers/SingleWidgetController.kt b/src/backend/src/main/kotlin/org/icpclive/controllers/SingleWidgetController.kt
index c7207a0e4..b0f6ea4e9 100644
--- a/src/backend/src/main/kotlin/org/icpclive/controllers/SingleWidgetController.kt
+++ b/src/backend/src/main/kotlin/org/icpclive/controllers/SingleWidgetController.kt
@@ -45,7 +45,9 @@ abstract class SingleWidgetController<SettingsType : ObjectSettings, DataType :
         overlayWidgetId = null
     }
 
+    @IgnorableReturnValue
     fun launchWhileWidgetExists(block: suspend () -> Unit) = widgetScope.launch { block() }
+    @IgnorableReturnValue
     fun launchWhileWidgetShown(block: suspend () -> Unit) = widgetShowScope?.launch { block() }
 
     suspend fun getSettings() = mutex.withLock { settings }
diff --git a/src/backend/src/main/kotlin/org/icpclive/data/Manager.kt b/src/backend/src/main/kotlin/org/icpclive/data/Manager.kt
index 548244d38..c534e2b0d 100644
--- a/src/backend/src/main/kotlin/org/icpclive/data/Manager.kt
+++ b/src/backend/src/main/kotlin/org/icpclive/data/Manager.kt
@@ -31,6 +31,7 @@ abstract class ManagerWithEvents<T : TypeWithId, E> : Manager<T>() {
         items.forEach(block)
     }
 
+    @IgnorableReturnValue
     private fun removeById(id: String) : Boolean {
         val myItems = items.filter { it.id == id }
         for (item in myItems) {
diff --git a/src/cds-converter/src/main/kotlin/org/icpclive/converter/export/clics/ClicsExporter.kt b/src/cds-converter/src/main/kotlin/org/icpclive/converter/export/clics/ClicsExporter.kt
index 2bffe6e8f..4fa997aab 100644
--- a/src/cds-converter/src/main/kotlin/org/icpclive/converter/export/clics/ClicsExporter.kt
+++ b/src/cds-converter/src/main/kotlin/org/icpclive/converter/export/clics/ClicsExporter.kt
@@ -119,11 +119,9 @@ internal class ClicsExporter(private val mediaDirectory: Path) : Exporter {
                             .normalize()
                             .takeIf { it.startsWith(mediaDirectory) }
                             ?.takeIf { it.exists() }
-                        if (local != null) {
-                            "media/" + local.relativeTo(mediaDirectory).joinToString("/", prefix = "media/").also {
-                                localFiles[local] = it
-                            }
-                        }
+                        local?.relativeTo(mediaDirectory)
+                            ?.joinToString("/", prefix = "media/")
+                            ?.also { localFiles[local] = it }
                     }
                     url.value
                 }
diff --git a/src/cds/core/api/core.api b/src/cds/core/api/core.api
index c7a1d8e99..ddb227f96 100644
--- a/src/cds/core/api/core.api
+++ b/src/cds/core/api/core.api
@@ -3267,8 +3267,8 @@ public final class org/icpclive/cds/tunning/TemplateSubstitutionBuilder {
 	public final fun addJson (Ljava/lang/String;Lkotlinx/serialization/json/JsonElement;)V
 	public final fun addOrganization (Lorg/icpclive/cds/api/OrganizationInfo;Ljava/lang/String;)V
 	public static synthetic fun addOrganization$default (Lorg/icpclive/cds/tunning/TemplateSubstitutionBuilder;Lorg/icpclive/cds/api/OrganizationInfo;Ljava/lang/String;ILjava/lang/Object;)V
-	public final fun addRegex (Ljava/lang/String;Lorg/icpclive/cds/tunning/TemplateRegexParser;Ljava/lang/String;)Lorg/icpclive/cds/tunning/TemplateSubstitutionBuilder;
-	public static synthetic fun addRegex$default (Lorg/icpclive/cds/tunning/TemplateSubstitutionBuilder;Ljava/lang/String;Lorg/icpclive/cds/tunning/TemplateRegexParser;Ljava/lang/String;ILjava/lang/Object;)Lorg/icpclive/cds/tunning/TemplateSubstitutionBuilder;
+	public final fun addRegex (Ljava/lang/String;Lorg/icpclive/cds/tunning/TemplateRegexParser;Ljava/lang/String;)V
+	public static synthetic fun addRegex$default (Lorg/icpclive/cds/tunning/TemplateSubstitutionBuilder;Ljava/lang/String;Lorg/icpclive/cds/tunning/TemplateRegexParser;Ljava/lang/String;ILjava/lang/Object;)V
 	public final fun addTeam (Lorg/icpclive/cds/api/TeamInfo;Ljava/lang/String;Z)V
 	public static synthetic fun addTeam$default (Lorg/icpclive/cds/tunning/TemplateSubstitutionBuilder;Lorg/icpclive/cds/api/TeamInfo;Ljava/lang/String;ZILjava/lang/Object;)V
 	public final fun build ()Lorg/icpclive/cds/tunning/TemplateSubstitutor;
diff --git a/src/cds/core/src/main/kotlin/org/icpclive/cds/adapters/ContestState.kt b/src/cds/core/src/main/kotlin/org/icpclive/cds/adapters/ContestState.kt
index fbe8d7f89..c04c68012 100644
--- a/src/cds/core/src/main/kotlin/org/icpclive/cds/adapters/ContestState.kt
+++ b/src/cds/core/src/main/kotlin/org/icpclive/cds/adapters/ContestState.kt
@@ -44,6 +44,6 @@ public fun <T> Flow<T>.transformContestState(block: suspend FlowCollector<Contes
                 if (isUseless) return@collect
             }
             curContestState = curContestState.applyEvent(value)
-            curContestState?.let { emit(it) }
+            emit(curContestState)
         }
     }
diff --git a/src/cds/core/src/main/kotlin/org/icpclive/cds/tunning/Templates.kt b/src/cds/core/src/main/kotlin/org/icpclive/cds/tunning/Templates.kt
index eb7693e08..97ce43aa9 100644
--- a/src/cds/core/src/main/kotlin/org/icpclive/cds/tunning/Templates.kt
+++ b/src/cds/core/src/main/kotlin/org/icpclive/cds/tunning/Templates.kt
@@ -130,7 +130,7 @@ public class TemplateSubstitutionBuilder @PublishedApi internal constructor() {
     public fun addOrganization(info: OrganizationInfo, name: String = "org") {
         addJson(name, Json.encodeToJsonElement(info) as JsonObject)
     }
-    public fun addRegex(groupName: String, parser: TemplateRegexParser, name: String = "regexes") : TemplateSubstitutionBuilder = apply {
+    public fun addRegex(groupName: String, parser: TemplateRegexParser, name: String = "regexes") {
         fun <T> Result<T>.getOrNullAndWarn(regex: Regex, value: String, replacement: String? = null): T? {
             exceptionOrNull()?.let {
                 logger(OverrideTeamTemplate::class).error(it) {
diff --git a/src/cds/plugins/codedrills/build.gradle.kts b/src/cds/plugins/codedrills/build.gradle.kts
index 24ca68083..034e214a8 100644
--- a/src/cds/plugins/codedrills/build.gradle.kts
+++ b/src/cds/plugins/codedrills/build.gradle.kts
@@ -49,4 +49,5 @@ dependencies {
     runtimeOnly(libs.grpc.netty)
     implementation(libs.grpc.protobuf)
     implementation(libs.grpc.stub)
+    implementation(libs.grpc.kotlin.stub)
 }
\ No newline at end of file
diff --git a/src/cds/tests/src/test/kotlin/AllConfigsAreParsable.kt b/src/cds/tests/src/test/kotlin/AllConfigsAreParsable.kt
index 5fd57430e..511137583 100644
--- a/src/cds/tests/src/test/kotlin/AllConfigsAreParsable.kt
+++ b/src/cds/tests/src/test/kotlin/AllConfigsAreParsable.kt
@@ -16,13 +16,13 @@ class AllConfigsAreParsable {
     @OptIn(ExperimentalPathApi::class)
     private fun test(
         configDir: Path,
-        nameFileter: (String) -> Boolean,
-        parser: (Path) -> Unit
+        nameFilter: (String) -> Boolean,
+        parser: (Path) -> Any?
     ) : List<DynamicTest> {
         return configDir.walk()
-            .filter { nameFileter(it.name) }
+            .filter { nameFilter(it.name) }
             .map {
-                DynamicTest.dynamicTest(it.relativeTo(configDir).toString()) { parser(it) }
+                DynamicTest.dynamicTest(it.relativeTo(configDir).toString()) { val _ = parser(it) }
             }.toList()
             .also { require(it.isNotEmpty()) }
     }
@@ -32,7 +32,7 @@ class AllConfigsAreParsable {
     fun testSettings() : List<DynamicTest> {
         return test(
             Path("").absolute().parent.parent.parent.resolve("config"),
-            nameFileter = { it == "settings.json" },
+            nameFilter = { it == "settings.json" },
             parser = { CDSSettings.fromFile(it) { "" } }
         )
     }
@@ -42,7 +42,7 @@ class AllConfigsAreParsable {
     fun testAdvancedJson() : List<DynamicTest> {
         return test(
             Path("").absolute().parent.parent.parent.resolve("config"),
-            nameFileter = { it == "advanced.json" },
+            nameFilter = { it == "advanced.json" },
             parser = { path ->
                 path.toFile().inputStream().use {
                     TuningRule.listFromInputStream(it)
@@ -63,7 +63,7 @@ class AllConfigsAreParsable {
         }
         return test(
             projectDir.resolve("config"),
-            nameFileter = { it.startsWith("visual-config") || it.startsWith("visualConfig") },
+            nameFilter = { it.startsWith("visual-config") || it.startsWith("visualConfig") },
             parser = { path ->
                 path.toFile().inputStream().use {
                     jsonSchema.validate(json.decodeFromStream<JsonElement>(it)) {error ->
@@ -79,7 +79,7 @@ class AllConfigsAreParsable {
     fun testAdvancedJsonExamples() : List<DynamicTest> {
         return test(
             Path("").absolute().parent.parent.parent.resolve("config/_examples/_advanced"),
-            nameFileter = { true },
+            nameFilter = { true },
             parser = { path ->
                 path.toFile().inputStream().use {
                     TuningRule.listFromInputStream(it)
diff --git a/src/clics-api/src/test/kotlin/org/icpclive/clics/time/ClicsTimeTest.kt b/src/clics-api/src/test/kotlin/org/icpclive/clics/time/ClicsTimeTest.kt
index 9f7a65c89..3c32a651a 100644
--- a/src/clics-api/src/test/kotlin/org/icpclive/clics/time/ClicsTimeTest.kt
+++ b/src/clics-api/src/test/kotlin/org/icpclive/clics/time/ClicsTimeTest.kt
@@ -155,11 +155,11 @@ object ClicsTimeTest {
         )
 
         for (pp in relSigns) for (hh in relHours) for (mm in relMinutes) for (ss in relSeconds) {
-            hh.first ?: continue
-            mm.first ?: continue
+            if (hh.first == null) continue
+            if (mm.first == null) continue
             val duration = (hh.second.hours + mm.second.minutes + ss.second.seconds) * pp.second
             val durationString = formatClicsRelativeTime(duration)
-            parseClicsRelativeTime(durationString)
+            parseClicsRelativeTime(durationString).also { assertEquals(duration, it) }
             val obj = ObjectWithDuration(duration)
             val encodedString = Json.encodeToString(obj)
             assertEquals("{\"dur\":\"$durationString\"}", encodedString)
diff --git a/src/oracle-tools/src/main/kotlin/org/icpclive/oracle/Admin.kt b/src/oracle-tools/src/main/kotlin/org/icpclive/oracle/Admin.kt
index 31b9733cb..39e5d72c9 100644
--- a/src/oracle-tools/src/main/kotlin/org/icpclive/oracle/Admin.kt
+++ b/src/oracle-tools/src/main/kotlin/org/icpclive/oracle/Admin.kt
@@ -17,8 +17,7 @@ fun Route.setupRouting() {
         call.adminApiAction {
             log.info { "hello!!!" }
             val request = call.receive<OracleRequest>()
-            OracleMover.moveToTeam(request.oracleId, request.teamId)
-            Unit
+            val _ = OracleMover.moveToTeam(request.oracleId, request.teamId)
         }
     }
 
diff --git a/src/oracle-tools/src/main/kotlin/org/icpclive/oracle/OracleCalibrator.kt b/src/oracle-tools/src/main/kotlin/org/icpclive/oracle/OracleCalibrator.kt
index 7f9e96b03..93566bb47 100644
--- a/src/oracle-tools/src/main/kotlin/org/icpclive/oracle/OracleCalibrator.kt
+++ b/src/oracle-tools/src/main/kotlin/org/icpclive/oracle/OracleCalibrator.kt
@@ -1,3 +1,5 @@
+@file:Suppress("PLATFORM_CLASS_MAPPED_TO_KOTLIN")
+
 package org.icpclive.oracle
 
 import kotlinx.coroutines.runBlocking