diff --git a/backend/build.gradle.kts b/backend/build.gradle.kts
index 96eb45ef..840ca544 100644
--- a/backend/build.gradle.kts
+++ b/backend/build.gradle.kts
@@ -2,12 +2,12 @@ import org.jetbrains.kotlin.gradle.dsl.JvmTarget
 import org.jetbrains.kotlin.gradle.tasks.KotlinCompile
 
 plugins {
-    id("org.springframework.boot") version "3.5.5"
+    id("org.springframework.boot") version "4.0.0-RC2"
     id("io.spring.dependency-management") version "1.1.7"
-    id("org.owasp.dependencycheck") version "12.1.3"
-    kotlin("jvm") version "2.2.10"
-    kotlin("plugin.spring") version "2.2.10"
-    id("org.sonarqube") version "6.2.0.5505"
+    id("org.owasp.dependencycheck") version "12.1.9"
+    kotlin("jvm") version "2.2.21"
+    kotlin("plugin.spring") version "2.2.21"
+    id("org.sonarqube") version "7.0.1.6134"
 }
 
 group = "hu.bme.sch"
@@ -42,52 +42,49 @@ repositories {
 }
 
 dependencies {
-    implementation("com.google.firebase:firebase-admin:9.5.0")
-    implementation("software.amazon.awssdk:s3:2.32.29")
-    implementation("jakarta.xml.bind:jakarta.xml.bind-api:4.0.2")
-    implementation("org.springframework.boot:spring-boot-configuration-processor")
-    implementation("org.springframework.boot:spring-boot-starter-data-jpa")
-    implementation("org.springframework.boot:spring-boot-starter-oauth2-client")
-    implementation("org.springframework.boot:spring-boot-starter-security")
-    implementation("org.springframework.boot:spring-boot-starter-web")
-    implementation("org.springframework.boot:spring-boot-starter-webflux")
-    implementation("org.springframework.boot:spring-boot-starter-thymeleaf")
-    implementation("org.springframework.boot:spring-boot-starter-actuator")
-    implementation("org.springframework.boot:spring-boot-starter-validation")
-    implementation("org.springframework.session:spring-session-jdbc")
-    implementation("org.springframework.retry:spring-retry")
-    implementation("org.springframework.boot:spring-boot-starter-aop")
+    annotationProcessor("org.springframework.boot:spring-boot-configuration-processor")
+    developmentOnly("org.springframework.boot:spring-boot-devtools")
+    implementation("com.fasterxml.jackson.dataformat:jackson-dataformat-csv")
     implementation("com.fasterxml.jackson.module:jackson-module-kotlin")
-    implementation("com.squareup.okhttp3:okhttp:5.1.0")
-    implementation("com.itextpdf:itext-core:9.2.0")
+    implementation("com.fasterxml.uuid:java-uuid-generator:5.1.1")
     implementation("com.github.spullara.mustache.java:compiler:0.9.14")
+    implementation("com.google.firebase:firebase-admin:9.7.0")
+    implementation("com.google.zxing:core:3.5.4")
+    implementation("com.google.zxing:javase:3.5.4")
+    implementation("com.itextpdf:itext-core:9.4.0")
+    implementation("com.squareup.okhttp3:okhttp:5.3.0")
+    implementation(platform("io.jsonwebtoken:jjwt-bom:0.13.0"))
+    runtimeOnly("io.jsonwebtoken:jjwt-impl")
+    runtimeOnly("io.jsonwebtoken:jjwt-jackson")
+    implementation("io.jsonwebtoken:jjwt-api")
+    implementation(platform("io.micrometer:micrometer-bom:1.16.0"))
+    implementation("io.micrometer:micrometer-core")
+    implementation("io.micrometer:micrometer-observation")
+    implementation("io.micrometer:micrometer-registry-prometheus")
+    implementation("org.commonmark:commonmark-ext-gfm-tables:0.27.0")
+    implementation("org.commonmark:commonmark:0.27.0")
     implementation("org.jetbrains.kotlin:kotlin-reflect")
-    implementation("org.jetbrains.kotlin:kotlin-stdlib-jdk8")
-    implementation("org.springdoc:springdoc-openapi-starter-webmvc-ui:2.8.11")
-    implementation("com.google.zxing:core:3.5.3")
-    implementation("com.google.zxing:javase:3.5.3")
     implementation("org.jetbrains.kotlin:kotlin-scripting-common")
-    implementation("org.jetbrains.kotlin:kotlin-scripting-jvm")
-    implementation("org.jetbrains.kotlin:kotlin-scripting-jvm-host")
     implementation("org.jetbrains.kotlin:kotlin-scripting-dependencies")
     implementation("org.jetbrains.kotlin:kotlin-scripting-dependencies-maven")
+    implementation("org.jetbrains.kotlin:kotlin-scripting-jvm")
+    implementation("org.jetbrains.kotlin:kotlin-scripting-jvm-host")
+    implementation("org.jetbrains.kotlin:kotlin-stdlib-jdk8")
     implementation("org.jetbrains.kotlinx:kotlinx-coroutines-core:1.10.2")
-    implementation(platform("io.jsonwebtoken:jjwt-bom:0.13.0"))
-    implementation("io.jsonwebtoken:jjwt-api")
-    runtimeOnly("io.jsonwebtoken:jjwt-impl")
-    runtimeOnly("io.jsonwebtoken:jjwt-jackson")
-    implementation("com.fasterxml.uuid:java-uuid-generator:5.1.0")
-    implementation("org.commonmark:commonmark:0.25.1")
-    implementation("org.commonmark:commonmark-ext-gfm-tables:0.25.1")
-    implementation("com.fasterxml.jackson.dataformat:jackson-dataformat-csv")
-    developmentOnly("org.springframework.boot:spring-boot-devtools")
-    annotationProcessor("org.springframework.boot:spring-boot-configuration-processor")
+    implementation("org.springdoc:springdoc-openapi-starter-webmvc-ui:3.0.0-RC1")
+    implementation("org.springframework.boot:spring-boot-configuration-processor")
+    implementation("org.springframework.boot:spring-boot-starter-actuator")
+    implementation("org.springframework.boot:spring-boot-starter-data-jpa")
+    implementation("org.springframework.boot:spring-boot-starter-oauth2-client")
+    implementation("org.springframework.boot:spring-boot-starter-security")
+    implementation("org.springframework.boot:spring-boot-starter-thymeleaf")
+    implementation("org.springframework.boot:spring-boot-starter-validation")
+    implementation("org.springframework.boot:spring-boot-starter-web")
+    implementation("org.springframework.boot:spring-boot-starter-webclient")
+    implementation("org.springframework.session:spring-session-jdbc")
+    implementation("software.amazon.awssdk:s3:2.38.7")
     runtimeOnly("com.h2database:h2")
-    implementation("org.postgresql:postgresql")
-    implementation(platform("io.micrometer:micrometer-bom:1.15.3"))
-    implementation("io.micrometer:micrometer-core")
-    implementation("io.micrometer:micrometer-registry-prometheus")
-    implementation("io.micrometer:micrometer-observation")
+    runtimeOnly("org.postgresql:postgresql")
     testApi("org.springframework.boot:spring-boot-starter-test")
     testApi("org.springframework.security:spring-security-test")
 }
diff --git a/backend/gradle/wrapper/gradle-wrapper.jar b/backend/gradle/wrapper/gradle-wrapper.jar
index 1b33c55b..f8e1ee31 100644
Binary files a/backend/gradle/wrapper/gradle-wrapper.jar and b/backend/gradle/wrapper/gradle-wrapper.jar differ
diff --git a/backend/gradle/wrapper/gradle-wrapper.properties b/backend/gradle/wrapper/gradle-wrapper.properties
index ff23a68d..bad7c246 100644
--- a/backend/gradle/wrapper/gradle-wrapper.properties
+++ b/backend/gradle/wrapper/gradle-wrapper.properties
@@ -1,6 +1,6 @@
 distributionBase=GRADLE_USER_HOME
 distributionPath=wrapper/dists
-distributionUrl=https\://services.gradle.org/distributions/gradle-8.14.2-bin.zip
+distributionUrl=https\://services.gradle.org/distributions/gradle-9.2.0-bin.zip
 networkTimeout=10000
 validateDistributionUrl=true
 zipStoreBase=GRADLE_USER_HOME
diff --git a/backend/gradlew b/backend/gradlew
index 23d15a93..adff685a 100755
--- a/backend/gradlew
+++ b/backend/gradlew
@@ -1,7 +1,7 @@
 #!/bin/sh
 
 #
-# Copyright © 2015-2021 the original authors.
+# Copyright © 2015 the original authors.
 #
 # Licensed under the Apache License, Version 2.0 (the "License");
 # you may not use this file except in compliance with the License.
@@ -114,7 +114,6 @@ case "$( uname )" in                #(
   NONSTOP* )        nonstop=true ;;
 esac
 
-CLASSPATH="\\\"\\\""
 
 
 # Determine the Java command to use to start the JVM.
@@ -172,7 +171,6 @@ fi
 # For Cygwin or MSYS, switch paths to Windows format before running java
 if "$cygwin" || "$msys" ; then
     APP_HOME=$( cygpath --path --mixed "$APP_HOME" )
-    CLASSPATH=$( cygpath --path --mixed "$CLASSPATH" )
 
     JAVACMD=$( cygpath --unix "$JAVACMD" )
 
@@ -212,7 +210,6 @@ DEFAULT_JVM_OPTS='"-Xmx64m" "-Xms64m"'
 
 set -- \
         "-Dorg.gradle.appname=$APP_BASE_NAME" \
-        -classpath "$CLASSPATH" \
         -jar "$APP_HOME/gradle/wrapper/gradle-wrapper.jar" \
         "$@"
 
diff --git a/backend/gradlew.bat b/backend/gradlew.bat
index db3a6ac2..c4bdd3ab 100644
--- a/backend/gradlew.bat
+++ b/backend/gradlew.bat
@@ -70,11 +70,10 @@ goto fail
 :execute
 @rem Setup the command line
 
-set CLASSPATH=
 
 
 @rem Execute Gradle
-"%JAVA_EXE%" %DEFAULT_JVM_OPTS% %JAVA_OPTS% %GRADLE_OPTS% "-Dorg.gradle.appname=%APP_BASE_NAME%" -classpath "%CLASSPATH%" -jar "%APP_HOME%\gradle\wrapper\gradle-wrapper.jar" %*
+"%JAVA_EXE%" %DEFAULT_JVM_OPTS% %JAVA_OPTS% %GRADLE_OPTS% "-Dorg.gradle.appname=%APP_BASE_NAME%" -jar "%APP_HOME%\gradle\wrapper\gradle-wrapper.jar" %*
 
 :end
 @rem End local scope for the variables with windows NT shell
diff --git a/backend/src/main/kotlin/hu/bme/sch/cmsch/CMSchApplication.kt b/backend/src/main/kotlin/hu/bme/sch/cmsch/CMSchApplication.kt
index 729e3704..5bbedda0 100644
--- a/backend/src/main/kotlin/hu/bme/sch/cmsch/CMSchApplication.kt
+++ b/backend/src/main/kotlin/hu/bme/sch/cmsch/CMSchApplication.kt
@@ -4,8 +4,8 @@ import hu.bme.sch.cmsch.component.app.ApplicationComponent
 import hu.bme.sch.cmsch.config.ComponentLoadConfig
 import hu.bme.sch.cmsch.config.StartupPropertyConfig
 import org.springframework.boot.autoconfigure.SpringBootApplication
-import org.springframework.boot.autoconfigure.domain.EntityScan
 import org.springframework.boot.context.properties.EnableConfigurationProperties
+import org.springframework.boot.persistence.autoconfigure.EntityScan
 import org.springframework.boot.runApplication
 
 @SpringBootApplication
diff --git a/backend/src/main/kotlin/hu/bme/sch/cmsch/addon/nova/NovaIntegrationService.kt b/backend/src/main/kotlin/hu/bme/sch/cmsch/addon/nova/NovaIntegrationService.kt
index 744004c8..299e0484 100644
--- a/backend/src/main/kotlin/hu/bme/sch/cmsch/addon/nova/NovaIntegrationService.kt
+++ b/backend/src/main/kotlin/hu/bme/sch/cmsch/addon/nova/NovaIntegrationService.kt
@@ -16,8 +16,7 @@ import hu.bme.sch.cmsch.repository.UserRepository
 import hu.bme.sch.cmsch.service.TimeService
 import org.slf4j.LoggerFactory
 import org.springframework.boot.autoconfigure.condition.ConditionalOnProperty
-import org.springframework.retry.annotation.Backoff
-import org.springframework.retry.annotation.Retryable
+import org.springframework.resilience.annotation.Retryable
 import org.springframework.stereotype.Service
 import org.springframework.transaction.annotation.Isolation
 import org.springframework.transaction.annotation.Transactional
@@ -46,7 +45,7 @@ class NovaIntegrationService(
 
     private val log = LoggerFactory.getLogger(javaClass)
 
-    @Retryable(value = [ SQLException::class ], maxAttempts = 5, backoff = Backoff(delay = 500L, multiplier = 1.5))
+    @Retryable(value = [ SQLException::class ], maxAttempts = 5, delay = 500L, multiplier = 1.5)
     @Transactional(readOnly = false, isolation = Isolation.SERIALIZABLE)
     fun updateSubmissions(emails: List<String>): Int {
         val form = formRepository.findAll().firstOrNull { it.selected }
@@ -74,7 +73,7 @@ class NovaIntegrationService(
         return successful
     }
 
-    @Retryable(value = [ SQLException::class ], maxAttempts = 5, backoff = Backoff(delay = 500L, multiplier = 1.5))
+    @Retryable(value = [ SQLException::class ], maxAttempts = 5, delay = 500L, multiplier = 1.5)
     @Transactional(readOnly = true, isolation = Isolation.READ_COMMITTED)
     fun fetchSubmissions(): List<FilledOutFormDto> {
         val form = formRepository.findAll().firstOrNull { it.selected }
@@ -151,7 +150,7 @@ class NovaIntegrationService(
         }
     }
 
-    @Retryable(value = [ SQLException::class ], maxAttempts = 5, backoff = Backoff(delay = 500L, multiplier = 1.5))
+    @Retryable(value = [ SQLException::class ], maxAttempts = 5, delay = 500L, multiplier = 1.5)
     @Transactional(readOnly = false, isolation = Isolation.SERIALIZABLE)
     fun setPaymentStatus(email: String, status: Boolean, rejectionMessage: String?) {
         val form = formRepository.findAll().firstOrNull { it.selected }
@@ -173,7 +172,7 @@ class NovaIntegrationService(
             }
     }
 
-    @Retryable(value = [ SQLException::class ], maxAttempts = 5, backoff = Backoff(delay = 500L, multiplier = 1.5))
+    @Retryable(value = [ SQLException::class ], maxAttempts = 5, delay = 500L, multiplier = 1.5)
     @Transactional(readOnly = false, isolation = Isolation.SERIALIZABLE)
     fun setDetailsStatus(email: String, status: Boolean, rejectionMessage: String?) {
         val form = formRepository.findAll().firstOrNull { it.selected }
@@ -195,7 +194,7 @@ class NovaIntegrationService(
             }
     }
 
-    @Retryable(value = [ SQLException::class ], maxAttempts = 5, backoff = Backoff(delay = 500L, multiplier = 1.5))
+    @Retryable(value = [ SQLException::class ], maxAttempts = 5, delay = 500L, multiplier = 1.5)
     @Transactional(readOnly = false, isolation = Isolation.SERIALIZABLE)
     fun setAvatarStatus(email: String, status: Boolean, rejectionMessage: String?) {
         val user = userRepository.findByEmail(email).orElse(null) ?: return
@@ -218,7 +217,7 @@ class NovaIntegrationService(
         }
     }
 
-    @Retryable(value = [ SQLException::class ], maxAttempts = 5, backoff = Backoff(delay = 500L, multiplier = 1.5))
+    @Retryable(value = [ SQLException::class ], maxAttempts = 5, delay = 500L, multiplier = 1.5)
     @Transactional(readOnly = false, isolation = Isolation.SERIALIZABLE)
     fun setCvStatus(email: String, status: Boolean, rejectionMessage: String?) {
         val user = userRepository.findByEmail(email).orElse(null) ?: return
diff --git a/backend/src/main/kotlin/hu/bme/sch/cmsch/admin/CsvParserUtil.kt b/backend/src/main/kotlin/hu/bme/sch/cmsch/admin/CsvParserUtil.kt
index 29193e57..016ff5cf 100644
--- a/backend/src/main/kotlin/hu/bme/sch/cmsch/admin/CsvParserUtil.kt
+++ b/backend/src/main/kotlin/hu/bme/sch/cmsch/admin/CsvParserUtil.kt
@@ -57,9 +57,9 @@ class CsvParserUtil<T : Any>(private val type: KClass<T>) {
         return writer.writeValue(outputStream, data)
     }
 
-    fun importFromCsv(inputStream: InputStream): List<T> {
+    fun importFromCsv(inputStream: InputStream): MutableList<T> {
         val reader = mapper.readerFor(type.java).with(readerSchema)
         return reader.readValues<T>(inputStream).readAll()
     }
 
-}
\ No newline at end of file
+}
diff --git a/backend/src/main/kotlin/hu/bme/sch/cmsch/component/admission/AdmissionComponentEntityConfiguration.kt b/backend/src/main/kotlin/hu/bme/sch/cmsch/component/admission/AdmissionComponentEntityConfiguration.kt
index f9c405e9..879ca5e3 100644
--- a/backend/src/main/kotlin/hu/bme/sch/cmsch/component/admission/AdmissionComponentEntityConfiguration.kt
+++ b/backend/src/main/kotlin/hu/bme/sch/cmsch/component/admission/AdmissionComponentEntityConfiguration.kt
@@ -1,7 +1,7 @@
 package hu.bme.sch.cmsch.component.admission
 
 import org.springframework.boot.autoconfigure.condition.ConditionalOnBean
-import org.springframework.boot.autoconfigure.domain.EntityScan
+import org.springframework.boot.persistence.autoconfigure.EntityScan
 import org.springframework.context.annotation.Configuration
 
 @Configuration
diff --git a/backend/src/main/kotlin/hu/bme/sch/cmsch/component/app/ApplicationApiController.kt b/backend/src/main/kotlin/hu/bme/sch/cmsch/component/app/ApplicationApiController.kt
index 12d96328..339fc099 100644
--- a/backend/src/main/kotlin/hu/bme/sch/cmsch/component/app/ApplicationApiController.kt
+++ b/backend/src/main/kotlin/hu/bme/sch/cmsch/component/app/ApplicationApiController.kt
@@ -64,7 +64,7 @@ class ApplicationApiController(
                 return ApplicationConfigDto(
                     role = role,
                     menu = listOf(),
-                    components = componentWriter.writeValueAsString(components)
+                    components = components
                 )
             }
         }
@@ -74,7 +74,7 @@ class ApplicationApiController(
         return ApplicationConfigDto(
             role = role,
             menu = menuService.getCachedMenuForRole(role),
-            components = componentWriter.writeValueAsString(components)
+            components = components
         )
     }
 
diff --git a/backend/src/main/kotlin/hu/bme/sch/cmsch/component/app/ApplicationConfigDto.kt b/backend/src/main/kotlin/hu/bme/sch/cmsch/component/app/ApplicationConfigDto.kt
index 330fba7a..50ae9a5f 100644
--- a/backend/src/main/kotlin/hu/bme/sch/cmsch/component/app/ApplicationConfigDto.kt
+++ b/backend/src/main/kotlin/hu/bme/sch/cmsch/component/app/ApplicationConfigDto.kt
@@ -1,9 +1,5 @@
 package hu.bme.sch.cmsch.component.app
 
-import com.fasterxml.jackson.core.JsonGenerator
-import com.fasterxml.jackson.databind.JsonSerializer
-import com.fasterxml.jackson.databind.SerializerProvider
-import com.fasterxml.jackson.databind.annotation.JsonSerialize
 import hu.bme.sch.cmsch.model.RoleType
 
 data class ApplicationConfigDto(
@@ -11,12 +7,5 @@ data class ApplicationConfigDto(
     var menu: List<MenuItem>,
 
     // Components -> properties -> values: Map<String, Map<String, Any>>
-    @field:JsonSerialize(using = ApplicationConfigFastSerializer::class)
-    var components: String
+    var components: Map<String, Any>
 )
-
-class ApplicationConfigFastSerializer : JsonSerializer<String>() {
-    override fun serialize(value: String?, gen: JsonGenerator?, serializers: SerializerProvider?) {
-        gen?.writeRawValue(value ?: "")
-    }
-}
\ No newline at end of file
diff --git a/backend/src/main/kotlin/hu/bme/sch/cmsch/component/app/MenuService.kt b/backend/src/main/kotlin/hu/bme/sch/cmsch/component/app/MenuService.kt
index d4e693b6..1614cddf 100644
--- a/backend/src/main/kotlin/hu/bme/sch/cmsch/component/app/MenuService.kt
+++ b/backend/src/main/kotlin/hu/bme/sch/cmsch/component/app/MenuService.kt
@@ -14,8 +14,7 @@ import org.slf4j.LoggerFactory
 import org.springframework.boot.autoconfigure.condition.ConditionalOnBean
 import org.springframework.context.event.ContextRefreshedEvent
 import org.springframework.context.event.EventListener
-import org.springframework.retry.annotation.Backoff
-import org.springframework.retry.annotation.Retryable
+import org.springframework.resilience.annotation.Retryable
 import org.springframework.stereotype.Service
 import org.springframework.transaction.PlatformTransactionManager
 import org.springframework.transaction.annotation.Isolation
@@ -131,7 +130,7 @@ class MenuService(
         }
     }
 
-    @Retryable(value = [ SQLException::class ], maxAttempts = 5, backoff = Backoff(delay = 500L, multiplier = 1.5))
+    @Retryable(value = [ SQLException::class ], maxAttempts = 5, delay = 500L, multiplier = 1.5)
     @Transactional(readOnly = false, isolation = Isolation.SERIALIZABLE)
     fun persistSettings(menus: List<MenuSettingItem>, role: RoleType) {
         menuRepository.deleteAllByRole(role)
@@ -197,7 +196,7 @@ class MenuService(
         var external: Boolean = false,
     )
 
-    @Retryable(value = [ SQLException::class ], maxAttempts = 5, backoff = Backoff(delay = 500L, multiplier = 1.5))
+    @Retryable(value = [ SQLException::class ], maxAttempts = 5, delay = 500L, multiplier = 1.5)
     @Transactional(readOnly = false, isolation = Isolation.SERIALIZABLE)
     fun importMenu(entries: List<MenuImportEntry>, rolesToInclude: List<RoleType>): Pair<Int, Int> {
         var imported = 0
diff --git a/backend/src/main/kotlin/hu/bme/sch/cmsch/component/bmejegy/BmejegyComponentEntityConfiguration.kt b/backend/src/main/kotlin/hu/bme/sch/cmsch/component/bmejegy/BmejegyComponentEntityConfiguration.kt
index d9d109ff..4c29ec78 100644
--- a/backend/src/main/kotlin/hu/bme/sch/cmsch/component/bmejegy/BmejegyComponentEntityConfiguration.kt
+++ b/backend/src/main/kotlin/hu/bme/sch/cmsch/component/bmejegy/BmejegyComponentEntityConfiguration.kt
@@ -1,7 +1,7 @@
 package hu.bme.sch.cmsch.component.bmejegy
 
 import org.springframework.boot.autoconfigure.condition.ConditionalOnBean
-import org.springframework.boot.autoconfigure.domain.EntityScan
+import org.springframework.boot.persistence.autoconfigure.EntityScan
 import org.springframework.context.annotation.Configuration
 
 @Configuration
diff --git a/backend/src/main/kotlin/hu/bme/sch/cmsch/component/bmejegy/BmejegyRecordRepository.kt b/backend/src/main/kotlin/hu/bme/sch/cmsch/component/bmejegy/BmejegyRecordRepository.kt
index b8e2d289..9548b139 100644
--- a/backend/src/main/kotlin/hu/bme/sch/cmsch/component/bmejegy/BmejegyRecordRepository.kt
+++ b/backend/src/main/kotlin/hu/bme/sch/cmsch/component/bmejegy/BmejegyRecordRepository.kt
@@ -10,7 +10,7 @@ import org.springframework.stereotype.Repository
 interface BmejegyRecordRepository : CrudRepository<BmejegyRecordEntity, Int>,
     EntityPageDataSource<BmejegyRecordEntity, Int> {
 
-    override fun findAll(): List<BmejegyRecordEntity>
+    override fun findAll(): MutableIterable<BmejegyRecordEntity>
 
     fun findAllByQrCode(qr: String): List<BmejegyRecordEntity>
 
diff --git a/backend/src/main/kotlin/hu/bme/sch/cmsch/component/bmejegy/CheersBmejegyService.kt b/backend/src/main/kotlin/hu/bme/sch/cmsch/component/bmejegy/CheersBmejegyService.kt
index cabc386e..11426b9a 100644
--- a/backend/src/main/kotlin/hu/bme/sch/cmsch/component/bmejegy/CheersBmejegyService.kt
+++ b/backend/src/main/kotlin/hu/bme/sch/cmsch/component/bmejegy/CheersBmejegyService.kt
@@ -13,13 +13,11 @@ import hu.bme.sch.cmsch.service.TimeService
 import org.slf4j.LoggerFactory
 import org.springframework.boot.autoconfigure.condition.ConditionalOnBean
 import org.springframework.boot.autoconfigure.condition.ConditionalOnProperty
-import org.springframework.retry.annotation.Backoff
-import org.springframework.retry.annotation.Retryable
+import org.springframework.resilience.annotation.Retryable
 import org.springframework.stereotype.Service
 import org.springframework.transaction.annotation.Isolation
 import org.springframework.transaction.annotation.Transactional
 import java.sql.SQLException
-import java.util.Optional
 
 @Service
 @ConditionalOnBean(BmejegyComponent::class)
@@ -70,7 +68,7 @@ class CheersBmejegyService(
         }
     }
 
-    @Retryable(value = [ SQLException::class ], maxAttempts = 5, backoff = Backoff(delay = 500L, multiplier = 1.5))
+    @Retryable(value = [ SQLException::class ], maxAttempts = 5, delay = 500L, multiplier = 1.5)
     @Transactional(readOnly = false, isolation = Isolation.SERIALIZABLE)
     fun updateUserStatuses() {
         val unmatched = bmejegyRecordRepository.findAllByMatchedUserId(0)
diff --git a/backend/src/main/kotlin/hu/bme/sch/cmsch/component/bmejegy/LegacyBmejegyService.kt b/backend/src/main/kotlin/hu/bme/sch/cmsch/component/bmejegy/LegacyBmejegyService.kt
index c1df5ffc..22b05be5 100644
--- a/backend/src/main/kotlin/hu/bme/sch/cmsch/component/bmejegy/LegacyBmejegyService.kt
+++ b/backend/src/main/kotlin/hu/bme/sch/cmsch/component/bmejegy/LegacyBmejegyService.kt
@@ -19,8 +19,7 @@ import org.springframework.http.HttpHeaders
 import org.springframework.http.MediaType
 import org.springframework.http.ResponseEntity
 import org.springframework.http.client.reactive.ReactorClientHttpConnector
-import org.springframework.retry.annotation.Backoff
-import org.springframework.retry.annotation.Retryable
+import org.springframework.resilience.annotation.Retryable
 import org.springframework.stereotype.Service
 import org.springframework.transaction.annotation.Isolation
 import org.springframework.transaction.annotation.Transactional
@@ -65,7 +64,7 @@ class LegacyBmejegyService(
         return Optional.ofNullable(bmejegyRecordRepository.findAllByQrCode(qr).firstOrNull())
     }
 
-    @Retryable(value = [ SQLException::class ], maxAttempts = 5, backoff = Backoff(delay = 500L, multiplier = 1.5))
+    @Retryable(value = [ SQLException::class ], maxAttempts = 5, delay = 500L, multiplier = 1.5)
     @Transactional(readOnly = false, isolation = Isolation.SERIALIZABLE)
     fun updateTickets(tickets: BmeJegyResponse) {
         val registered = bmejegyRecordRepository.findAll().associateBy { it.itemId }
@@ -101,7 +100,7 @@ class LegacyBmejegyService(
         }
     }
 
-    @Retryable(value = [ SQLException::class ], maxAttempts = 5, backoff = Backoff(delay = 500L, multiplier = 1.5))
+    @Retryable(value = [ SQLException::class ], maxAttempts = 5, delay = 500L, multiplier = 1.5)
     @Transactional(readOnly = false, isolation = Isolation.SERIALIZABLE)
     fun updateUserStatuses() {
         val unmatched = bmejegyRecordRepository.findAllByMatchedUserId(0)
diff --git a/backend/src/main/kotlin/hu/bme/sch/cmsch/component/challenge/ChallengeComponentEntityConfiguration.kt b/backend/src/main/kotlin/hu/bme/sch/cmsch/component/challenge/ChallengeComponentEntityConfiguration.kt
index 71c53055..9fd62fd3 100644
--- a/backend/src/main/kotlin/hu/bme/sch/cmsch/component/challenge/ChallengeComponentEntityConfiguration.kt
+++ b/backend/src/main/kotlin/hu/bme/sch/cmsch/component/challenge/ChallengeComponentEntityConfiguration.kt
@@ -1,7 +1,7 @@
 package hu.bme.sch.cmsch.component.challenge
 
 import org.springframework.boot.autoconfigure.condition.ConditionalOnBean
-import org.springframework.boot.autoconfigure.domain.EntityScan
+import org.springframework.boot.persistence.autoconfigure.EntityScan
 import org.springframework.context.annotation.Configuration
 
 @Configuration
diff --git a/backend/src/main/kotlin/hu/bme/sch/cmsch/component/communities/CommunitiesComponentEntityConfiguration.kt b/backend/src/main/kotlin/hu/bme/sch/cmsch/component/communities/CommunitiesComponentEntityConfiguration.kt
index 060ec097..f3025003 100644
--- a/backend/src/main/kotlin/hu/bme/sch/cmsch/component/communities/CommunitiesComponentEntityConfiguration.kt
+++ b/backend/src/main/kotlin/hu/bme/sch/cmsch/component/communities/CommunitiesComponentEntityConfiguration.kt
@@ -1,7 +1,7 @@
 package hu.bme.sch.cmsch.component.communities
 
 import org.springframework.boot.autoconfigure.condition.ConditionalOnBean
-import org.springframework.boot.autoconfigure.domain.EntityScan
+import org.springframework.boot.persistence.autoconfigure.EntityScan
 import org.springframework.context.annotation.Configuration
 
 @Configuration
diff --git a/backend/src/main/kotlin/hu/bme/sch/cmsch/component/communities/CommunityRepository.kt b/backend/src/main/kotlin/hu/bme/sch/cmsch/component/communities/CommunityRepository.kt
index 25dd75b1..5ad7cb5f 100644
--- a/backend/src/main/kotlin/hu/bme/sch/cmsch/component/communities/CommunityRepository.kt
+++ b/backend/src/main/kotlin/hu/bme/sch/cmsch/component/communities/CommunityRepository.kt
@@ -14,6 +14,6 @@ interface CommunityRepository : CrudRepository<CommunityEntity, Int>,
 
     override fun findById(id: Int): Optional<CommunityEntity>
 
-    override fun findAll(): List<CommunityEntity>
+    override fun findAll(): MutableList<CommunityEntity>
 
 }
diff --git a/backend/src/main/kotlin/hu/bme/sch/cmsch/component/communities/OrganizationRepository.kt b/backend/src/main/kotlin/hu/bme/sch/cmsch/component/communities/OrganizationRepository.kt
index aa441a83..958bb95d 100644
--- a/backend/src/main/kotlin/hu/bme/sch/cmsch/component/communities/OrganizationRepository.kt
+++ b/backend/src/main/kotlin/hu/bme/sch/cmsch/component/communities/OrganizationRepository.kt
@@ -14,6 +14,6 @@ interface OrganizationRepository : CrudRepository<OrganizationEntity, Int>,
 
     override fun findById(id: Int): Optional<OrganizationEntity>
 
-    override fun findAll(): List<OrganizationEntity>
+    override fun findAll(): MutableList<OrganizationEntity>
 
 }
diff --git a/backend/src/main/kotlin/hu/bme/sch/cmsch/component/conference/ConferenceComponentEntityConfiguration.kt b/backend/src/main/kotlin/hu/bme/sch/cmsch/component/conference/ConferenceComponentEntityConfiguration.kt
index f91833f1..8f3426f1 100644
--- a/backend/src/main/kotlin/hu/bme/sch/cmsch/component/conference/ConferenceComponentEntityConfiguration.kt
+++ b/backend/src/main/kotlin/hu/bme/sch/cmsch/component/conference/ConferenceComponentEntityConfiguration.kt
@@ -1,7 +1,7 @@
 package hu.bme.sch.cmsch.component.conference
 
 import org.springframework.boot.autoconfigure.condition.ConditionalOnBean
-import org.springframework.boot.autoconfigure.domain.EntityScan
+import org.springframework.boot.persistence.autoconfigure.EntityScan
 import org.springframework.context.annotation.Configuration
 
 @Configuration
diff --git a/backend/src/main/kotlin/hu/bme/sch/cmsch/component/conference/ConferenceRepositories.kt b/backend/src/main/kotlin/hu/bme/sch/cmsch/component/conference/ConferenceRepositories.kt
index d3e8a251..8e534877 100644
--- a/backend/src/main/kotlin/hu/bme/sch/cmsch/component/conference/ConferenceRepositories.kt
+++ b/backend/src/main/kotlin/hu/bme/sch/cmsch/component/conference/ConferenceRepositories.kt
@@ -8,7 +8,7 @@ import org.springframework.stereotype.Repository
 @Repository
 @ConditionalOnBean(ConferenceComponent::class)
 interface ConferenceRepository : CrudRepository<ConferenceEntity, Int>, EntityPageDataSource<ConferenceEntity, Int> {
-    override fun findAll(): List<ConferenceEntity>
+    override fun findAll(): MutableList<ConferenceEntity>
 }
 
 @Repository
@@ -35,4 +35,4 @@ interface ConferencePresentationRepository : CrudRepository<ConferencePresentati
 @ConditionalOnBean(ConferenceComponent::class)
 interface ConferenceOrganizerRepository : CrudRepository<ConferenceOrganizerEntity, Int>, EntityPageDataSource<ConferenceOrganizerEntity, Int> {
     fun findAllByVisibleTrue(): List<ConferenceOrganizerEntity>
-}
\ No newline at end of file
+}
diff --git a/backend/src/main/kotlin/hu/bme/sch/cmsch/component/conference/ConferenceSeedConfig.kt b/backend/src/main/kotlin/hu/bme/sch/cmsch/component/conference/ConferenceSeedConfig.kt
index f55de159..25482650 100644
--- a/backend/src/main/kotlin/hu/bme/sch/cmsch/component/conference/ConferenceSeedConfig.kt
+++ b/backend/src/main/kotlin/hu/bme/sch/cmsch/component/conference/ConferenceSeedConfig.kt
@@ -27,8 +27,7 @@ class ConferenceSeedConfig(
 
     private fun addConference() {
         if (conferenceRepository.count() != 0L) return
-        conferenceRepository.saveAll(
-            listOf(
+        conferenceRepository.saveAll(mutableListOf(
                 ConferenceEntity(
                     title = "Test Conference 2022",
                     priority = 0,
@@ -51,7 +50,7 @@ class ConferenceSeedConfig(
     private fun addCompanies() {
         if (conferenceCompanyRepository.count() != 0L) return
         conferenceCompanyRepository.saveAll(
-            listOf(
+            mutableListOf(
                 ConferenceCompanyEntity(
                     name = "Test Company 1",
                     selector = "test-company-1",
@@ -91,7 +90,7 @@ class ConferenceSeedConfig(
     private fun addPresenters() {
         if (conferencePresenterRepository.count() != 0L) return
         conferencePresenterRepository.saveAll(
-            listOf(
+            mutableListOf(
                 ConferencePresenterEntity(
                     name = "Test Presenter 1",
                     selector = "test-presenter-1",
@@ -123,7 +122,7 @@ class ConferenceSeedConfig(
     private fun addPresentations() {
         if (conferencePresentationRepository.count() != 0L) return
         conferencePresentationRepository.saveAll(
-            listOf(
+            mutableListOf(
                 ConferencePresentationEntity(
                     slug = "test-presentation-1",
                     title = "Test Presentation 1",
@@ -196,7 +195,7 @@ class ConferenceSeedConfig(
     private fun addOrganizers() {
         if (conferenceOrganizerRepository.count() != 0L) return
         conferenceOrganizerRepository.saveAll(
-            listOf(
+            mutableListOf(
                 ConferenceOrganizerEntity(
                     name = "Test Organizer 1",
                     rank = "Test Rank 1",
diff --git a/backend/src/main/kotlin/hu/bme/sch/cmsch/component/debt/DebtAdminDebtsByGroupController.kt b/backend/src/main/kotlin/hu/bme/sch/cmsch/component/debt/DebtAdminDebtsByGroupController.kt
index 89746d31..59f4c6ef 100644
--- a/backend/src/main/kotlin/hu/bme/sch/cmsch/component/debt/DebtAdminDebtsByGroupController.kt
+++ b/backend/src/main/kotlin/hu/bme/sch/cmsch/component/debt/DebtAdminDebtsByGroupController.kt
@@ -38,7 +38,7 @@ class DebtAdminDebtsByGroupController(
 
     transactionManager,
     object : ManualRepository<DebtsByGroupVirtualEntity, Int>() {
-        override fun findAll(): Iterable<DebtsByGroupVirtualEntity> {
+        override fun findAll(): MutableIterable<DebtsByGroupVirtualEntity> {
             return soldProductRepository.findAll().groupBy { it.responsibleGroupId }
                 .map { it.value }
                 .filter { it.isNotEmpty() }
@@ -51,7 +51,7 @@ class DebtAdminDebtsByGroupController(
                         debts.filter { !it.payed }.sumOf { it.price },
                         debts.filter { !it.finsihed }.sumOf { it.price }
                     )
-                }
+                }.toMutableList()
         }
 
     },
diff --git a/backend/src/main/kotlin/hu/bme/sch/cmsch/component/debt/DebtAdminDebtsByUsersController.kt b/backend/src/main/kotlin/hu/bme/sch/cmsch/component/debt/DebtAdminDebtsByUsersController.kt
index b1e5a4ce..ca25abb3 100644
--- a/backend/src/main/kotlin/hu/bme/sch/cmsch/component/debt/DebtAdminDebtsByUsersController.kt
+++ b/backend/src/main/kotlin/hu/bme/sch/cmsch/component/debt/DebtAdminDebtsByUsersController.kt
@@ -40,7 +40,7 @@ class DebtAdminDebtsByUsersController(
 
     transactionManager,
     object : ManualRepository<DebtsByUserVirtualEntity, Int>() {
-        override fun findAll(): Iterable<DebtsByUserVirtualEntity> {
+        override fun findAll(): MutableIterable<DebtsByUserVirtualEntity> {
             return soldProductRepository.findAll().groupBy { it.ownerId }
                 .map { it.value }
                 .filter { it.isNotEmpty() }
@@ -54,7 +54,7 @@ class DebtAdminDebtsByUsersController(
                         debts.filter { !it.payed }.sumOf { it.price },
                         debts.filter { !it.finsihed }.sumOf { it.price }
                     )
-                }
+                }.toMutableList()
         }
 
     },
diff --git a/backend/src/main/kotlin/hu/bme/sch/cmsch/component/debt/DebtComponentEntityConfiguration.kt b/backend/src/main/kotlin/hu/bme/sch/cmsch/component/debt/DebtComponentEntityConfiguration.kt
index 7058b138..2feead93 100644
--- a/backend/src/main/kotlin/hu/bme/sch/cmsch/component/debt/DebtComponentEntityConfiguration.kt
+++ b/backend/src/main/kotlin/hu/bme/sch/cmsch/component/debt/DebtComponentEntityConfiguration.kt
@@ -1,7 +1,7 @@
 package hu.bme.sch.cmsch.component.debt
 
 import org.springframework.boot.autoconfigure.condition.ConditionalOnBean
-import org.springframework.boot.autoconfigure.domain.EntityScan
+import org.springframework.boot.persistence.autoconfigure.EntityScan
 import org.springframework.context.annotation.Configuration
 
 @Configuration
diff --git a/backend/src/main/kotlin/hu/bme/sch/cmsch/component/debt/ProductRepository.kt b/backend/src/main/kotlin/hu/bme/sch/cmsch/component/debt/ProductRepository.kt
index 77d7a696..a5d3326e 100644
--- a/backend/src/main/kotlin/hu/bme/sch/cmsch/component/debt/ProductRepository.kt
+++ b/backend/src/main/kotlin/hu/bme/sch/cmsch/component/debt/ProductRepository.kt
@@ -10,7 +10,7 @@ import org.springframework.stereotype.Repository
 interface ProductRepository : CrudRepository<ProductEntity, Int>,
     EntityPageDataSource<ProductEntity, Int> {
 
-    override fun findAll(): List<ProductEntity>
+    override fun findAll(): MutableIterable<ProductEntity>
     fun findAllByType(type: ProductType): List<ProductEntity>
     fun findAllByTypeAndVisibleTrue(type: ProductType): List<ProductEntity>
 }
diff --git a/backend/src/main/kotlin/hu/bme/sch/cmsch/component/email/EmailComponentEntityConfiguration.kt b/backend/src/main/kotlin/hu/bme/sch/cmsch/component/email/EmailComponentEntityConfiguration.kt
index a6337787..60cf45d6 100644
--- a/backend/src/main/kotlin/hu/bme/sch/cmsch/component/email/EmailComponentEntityConfiguration.kt
+++ b/backend/src/main/kotlin/hu/bme/sch/cmsch/component/email/EmailComponentEntityConfiguration.kt
@@ -1,7 +1,7 @@
 package hu.bme.sch.cmsch.component.email
 
 import org.springframework.boot.autoconfigure.condition.ConditionalOnBean
-import org.springframework.boot.autoconfigure.domain.EntityScan
+import org.springframework.boot.persistence.autoconfigure.EntityScan
 import org.springframework.context.annotation.Configuration
 
 @Configuration
diff --git a/backend/src/main/kotlin/hu/bme/sch/cmsch/component/errorlog/ErrorLogComponentEntityConfiguration.kt b/backend/src/main/kotlin/hu/bme/sch/cmsch/component/errorlog/ErrorLogComponentEntityConfiguration.kt
index eb4a3956..c9654a6c 100644
--- a/backend/src/main/kotlin/hu/bme/sch/cmsch/component/errorlog/ErrorLogComponentEntityConfiguration.kt
+++ b/backend/src/main/kotlin/hu/bme/sch/cmsch/component/errorlog/ErrorLogComponentEntityConfiguration.kt
@@ -1,7 +1,7 @@
 package hu.bme.sch.cmsch.component.errorlog
 
 import org.springframework.boot.autoconfigure.condition.ConditionalOnBean
-import org.springframework.boot.autoconfigure.domain.EntityScan
+import org.springframework.boot.persistence.autoconfigure.EntityScan
 import org.springframework.context.annotation.Configuration
 
 @Configuration
diff --git a/backend/src/main/kotlin/hu/bme/sch/cmsch/component/errorlog/ErrorLogRepository.kt b/backend/src/main/kotlin/hu/bme/sch/cmsch/component/errorlog/ErrorLogRepository.kt
index b2cda46a..4a199ab5 100644
--- a/backend/src/main/kotlin/hu/bme/sch/cmsch/component/errorlog/ErrorLogRepository.kt
+++ b/backend/src/main/kotlin/hu/bme/sch/cmsch/component/errorlog/ErrorLogRepository.kt
@@ -13,7 +13,7 @@ import java.util.*
 interface ErrorLogRepository : CrudRepository<ErrorLogEntity, Int>, EntityPageDataSource<ErrorLogEntity, Int> {
 
     @Query("select e from ErrorLogEntity e order by e.lastReportedAt desc")
-    override fun findAll(): List<ErrorLogEntity>
+    override fun findAll(): MutableIterable<ErrorLogEntity>
 
     fun findByMessageAndStackAndUserAgentAndHrefAndRole(
         message: String,
diff --git a/backend/src/main/kotlin/hu/bme/sch/cmsch/component/event/EventComponentEntityConfiguration.kt b/backend/src/main/kotlin/hu/bme/sch/cmsch/component/event/EventComponentEntityConfiguration.kt
index efe42d77..d5b05334 100644
--- a/backend/src/main/kotlin/hu/bme/sch/cmsch/component/event/EventComponentEntityConfiguration.kt
+++ b/backend/src/main/kotlin/hu/bme/sch/cmsch/component/event/EventComponentEntityConfiguration.kt
@@ -1,7 +1,7 @@
 package hu.bme.sch.cmsch.component.event
 
 import org.springframework.boot.autoconfigure.condition.ConditionalOnBean
-import org.springframework.boot.autoconfigure.domain.EntityScan
+import org.springframework.boot.persistence.autoconfigure.EntityScan
 import org.springframework.context.annotation.Configuration
 
 @Configuration
diff --git a/backend/src/main/kotlin/hu/bme/sch/cmsch/component/event/EventRepository.kt b/backend/src/main/kotlin/hu/bme/sch/cmsch/component/event/EventRepository.kt
index e10af5e4..4c30b24d 100644
--- a/backend/src/main/kotlin/hu/bme/sch/cmsch/component/event/EventRepository.kt
+++ b/backend/src/main/kotlin/hu/bme/sch/cmsch/component/event/EventRepository.kt
@@ -9,7 +9,7 @@ import java.util.*
 @Repository
 @ConditionalOnBean(EventComponent::class)
 interface EventRepository : CrudRepository<EventEntity, Int>, EntityPageDataSource<EventEntity, Int> {
-    override fun findAll(): List<EventEntity>
+    override fun findAll(): MutableIterable<EventEntity>
     fun findByUrl(url: String): Optional<EventEntity>
     fun findAllByVisibleTrueOrderByTimestampStart(): List<EventEntity>
 }
diff --git a/backend/src/main/kotlin/hu/bme/sch/cmsch/component/form/FormComponentEntityConfiguration.kt b/backend/src/main/kotlin/hu/bme/sch/cmsch/component/form/FormComponentEntityConfiguration.kt
index 4174c96a..668be43e 100644
--- a/backend/src/main/kotlin/hu/bme/sch/cmsch/component/form/FormComponentEntityConfiguration.kt
+++ b/backend/src/main/kotlin/hu/bme/sch/cmsch/component/form/FormComponentEntityConfiguration.kt
@@ -1,7 +1,7 @@
 package hu.bme.sch.cmsch.component.form
 
 import org.springframework.boot.autoconfigure.condition.ConditionalOnBean
-import org.springframework.boot.autoconfigure.domain.EntityScan
+import org.springframework.boot.persistence.autoconfigure.EntityScan
 import org.springframework.context.annotation.Configuration
 
 @Configuration
diff --git a/backend/src/main/kotlin/hu/bme/sch/cmsch/component/form/FormService.kt b/backend/src/main/kotlin/hu/bme/sch/cmsch/component/form/FormService.kt
index 81a04394..e516d2aa 100644
--- a/backend/src/main/kotlin/hu/bme/sch/cmsch/component/form/FormService.kt
+++ b/backend/src/main/kotlin/hu/bme/sch/cmsch/component/form/FormService.kt
@@ -11,8 +11,7 @@ import hu.bme.sch.cmsch.repository.UserRepository
 import hu.bme.sch.cmsch.service.TimeService
 import org.slf4j.LoggerFactory
 import org.springframework.boot.autoconfigure.condition.ConditionalOnBean
-import org.springframework.retry.annotation.Backoff
-import org.springframework.retry.annotation.Retryable
+import org.springframework.resilience.annotation.Retryable
 import org.springframework.stereotype.Service
 import org.springframework.transaction.annotation.Isolation
 import org.springframework.transaction.annotation.Transactional
@@ -32,7 +31,7 @@ class FormService(
     private val emailService: Optional<EmailService>
 ) {
 
-    internal final val log = LoggerFactory.getLogger(javaClass)
+    internal val log = LoggerFactory.getLogger(javaClass)
 
     private final val objectMapper = jacksonObjectMapper()
     private final val gridReader = objectMapper.readerFor(FormGridValue::class.java)
@@ -148,7 +147,7 @@ class FormService(
     )
 
 
-    @Retryable(value = [SQLException::class], maxAttempts = 5, backoff = Backoff(delay = 500L, multiplier = 1.5))
+    @Retryable(value = [SQLException::class], maxAttempts = 5, delay = 500L, multiplier = 1.5)
     @Transactional(readOnly = false, isolation = Isolation.SERIALIZABLE)
     fun submitForm(user: CmschUser?, path: String, data: Map<String, String>, update: Boolean): FormSubmissionResult {
         val form = formRepository.findAllByUrl(path).getOrNull(0)
diff --git a/backend/src/main/kotlin/hu/bme/sch/cmsch/component/form/ResponseRepository.kt b/backend/src/main/kotlin/hu/bme/sch/cmsch/component/form/ResponseRepository.kt
index ee1fe986..1148f007 100644
--- a/backend/src/main/kotlin/hu/bme/sch/cmsch/component/form/ResponseRepository.kt
+++ b/backend/src/main/kotlin/hu/bme/sch/cmsch/component/form/ResponseRepository.kt
@@ -33,6 +33,6 @@ interface ResponseRepository : CrudRepository<ResponseEntity, Int>,
 
     fun findTop1ByFormIdAndEntryTokenOrderByLineDesc(formId: Int, entryToken: String): List<ResponseEntity>
 
-    override fun findAll(): List<ResponseEntity>
+    override fun findAll(): MutableList<ResponseEntity>
 
 }
diff --git a/backend/src/main/kotlin/hu/bme/sch/cmsch/component/form/ResponsesController.kt b/backend/src/main/kotlin/hu/bme/sch/cmsch/component/form/ResponsesController.kt
index 245ccc81..d8f71a3a 100644
--- a/backend/src/main/kotlin/hu/bme/sch/cmsch/component/form/ResponsesController.kt
+++ b/backend/src/main/kotlin/hu/bme/sch/cmsch/component/form/ResponsesController.kt
@@ -46,7 +46,7 @@ class ResponsesController(
 
     transactionManager,
     object : ManualRepository<FormVirtualEntity, Int>() {
-        override fun findAll(): Iterable<FormVirtualEntity> {
+        override fun findAll(): MutableIterable<FormVirtualEntity> {
             return formService.getAllResponses()
                 .groupBy { it.formId }
                 .map { it.value }
@@ -64,7 +64,7 @@ class ResponsesController(
                                 responses.count { it.detailsValidated },
                             )
                         }.orElse(null)
-                }
+                }.toMutableList()
         }
 
     },
diff --git a/backend/src/main/kotlin/hu/bme/sch/cmsch/component/gallery/GalleryComponentEntityConfiguration.kt b/backend/src/main/kotlin/hu/bme/sch/cmsch/component/gallery/GalleryComponentEntityConfiguration.kt
index 0f3e731a..92283c55 100644
--- a/backend/src/main/kotlin/hu/bme/sch/cmsch/component/gallery/GalleryComponentEntityConfiguration.kt
+++ b/backend/src/main/kotlin/hu/bme/sch/cmsch/component/gallery/GalleryComponentEntityConfiguration.kt
@@ -1,7 +1,7 @@
 package hu.bme.sch.cmsch.component.gallery
 
 import org.springframework.boot.autoconfigure.condition.ConditionalOnBean
-import org.springframework.boot.autoconfigure.domain.EntityScan
+import org.springframework.boot.persistence.autoconfigure.EntityScan
 import org.springframework.context.annotation.Configuration
 
 @Configuration
diff --git a/backend/src/main/kotlin/hu/bme/sch/cmsch/component/gallery/GalleryRepository.kt b/backend/src/main/kotlin/hu/bme/sch/cmsch/component/gallery/GalleryRepository.kt
index c2ee7122..8de9b01c 100644
--- a/backend/src/main/kotlin/hu/bme/sch/cmsch/component/gallery/GalleryRepository.kt
+++ b/backend/src/main/kotlin/hu/bme/sch/cmsch/component/gallery/GalleryRepository.kt
@@ -8,7 +8,7 @@ import org.springframework.stereotype.Repository
 @Repository
 @ConditionalOnBean(GalleryComponent::class)
 interface GalleryRepository : CrudRepository<GalleryEntity, Int>, EntityPageDataSource<GalleryEntity, Int> {
-    override fun findAll(): List<GalleryEntity>
+    override fun findAll(): MutableList<GalleryEntity>
 
     fun findByShowOnHomePage(showOnHomePage: Boolean): List<GalleryEntity>
 }
diff --git a/backend/src/main/kotlin/hu/bme/sch/cmsch/component/groupselection/GroupSelectionService.kt b/backend/src/main/kotlin/hu/bme/sch/cmsch/component/groupselection/GroupSelectionService.kt
index 92e4a04b..f00011c3 100644
--- a/backend/src/main/kotlin/hu/bme/sch/cmsch/component/groupselection/GroupSelectionService.kt
+++ b/backend/src/main/kotlin/hu/bme/sch/cmsch/component/groupselection/GroupSelectionService.kt
@@ -5,8 +5,7 @@ import hu.bme.sch.cmsch.repository.GroupRepository
 import hu.bme.sch.cmsch.repository.UserRepository
 import org.slf4j.LoggerFactory
 import org.springframework.boot.autoconfigure.condition.ConditionalOnBean
-import org.springframework.retry.annotation.Backoff
-import org.springframework.retry.annotation.Retryable
+import org.springframework.resilience.annotation.Retryable
 import org.springframework.stereotype.Service
 import org.springframework.transaction.annotation.Isolation
 import org.springframework.transaction.annotation.Transactional
@@ -21,7 +20,7 @@ class GroupSelectionService(
 
     private val log = LoggerFactory.getLogger(javaClass)
 
-    @Retryable(value = [ SQLException::class ], maxAttempts = 5, backoff = Backoff(delay = 500L, multiplier = 1.5))
+    @Retryable(value = [ SQLException::class ], maxAttempts = 5, delay = 500L, multiplier = 1.5)
     @Transactional(readOnly = false, isolation = Isolation.SERIALIZABLE)
     fun selectGroup(
         user: UserEntity,
diff --git a/backend/src/main/kotlin/hu/bme/sch/cmsch/component/key/AccessKeyComponentEntityConfiguration.kt b/backend/src/main/kotlin/hu/bme/sch/cmsch/component/key/AccessKeyComponentEntityConfiguration.kt
index 0ded042e..8a02cf79 100644
--- a/backend/src/main/kotlin/hu/bme/sch/cmsch/component/key/AccessKeyComponentEntityConfiguration.kt
+++ b/backend/src/main/kotlin/hu/bme/sch/cmsch/component/key/AccessKeyComponentEntityConfiguration.kt
@@ -1,7 +1,7 @@
 package hu.bme.sch.cmsch.component.key
 
 import org.springframework.boot.autoconfigure.condition.ConditionalOnBean
-import org.springframework.boot.autoconfigure.domain.EntityScan
+import org.springframework.boot.persistence.autoconfigure.EntityScan
 import org.springframework.context.annotation.Configuration
 
 @Configuration
diff --git a/backend/src/main/kotlin/hu/bme/sch/cmsch/component/key/AccessKeyRepository.kt b/backend/src/main/kotlin/hu/bme/sch/cmsch/component/key/AccessKeyRepository.kt
index 3bc27f9a..1db9db3e 100644
--- a/backend/src/main/kotlin/hu/bme/sch/cmsch/component/key/AccessKeyRepository.kt
+++ b/backend/src/main/kotlin/hu/bme/sch/cmsch/component/key/AccessKeyRepository.kt
@@ -9,10 +9,10 @@ import org.springframework.stereotype.Repository
 @ConditionalOnBean(AccessKeyComponent::class)
 interface AccessKeyRepository : CrudRepository<AccessKeyEntity, Int>, EntityPageDataSource<AccessKeyEntity, Int> {
 
-    override fun findAll(): List<AccessKeyEntity>
+    override fun findAll(): MutableIterable<AccessKeyEntity>
 
     fun findTop1ByUsedByUserId(userId: Int): List<AccessKeyEntity>
 
     fun findTop1ByAccessKey(accessKey: String): List<AccessKeyEntity>
 
-}
\ No newline at end of file
+}
diff --git a/backend/src/main/kotlin/hu/bme/sch/cmsch/component/key/AccessKeyService.kt b/backend/src/main/kotlin/hu/bme/sch/cmsch/component/key/AccessKeyService.kt
index 7061d9b5..c05c3805 100644
--- a/backend/src/main/kotlin/hu/bme/sch/cmsch/component/key/AccessKeyService.kt
+++ b/backend/src/main/kotlin/hu/bme/sch/cmsch/component/key/AccessKeyService.kt
@@ -7,8 +7,7 @@ import hu.bme.sch.cmsch.service.AuditLogService
 import hu.bme.sch.cmsch.service.TimeService
 import org.slf4j.LoggerFactory
 import org.springframework.boot.autoconfigure.condition.ConditionalOnBean
-import org.springframework.retry.annotation.Backoff
-import org.springframework.retry.annotation.Retryable
+import org.springframework.resilience.annotation.Retryable
 import org.springframework.stereotype.Service
 import org.springframework.transaction.annotation.Isolation
 import org.springframework.transaction.annotation.Transactional
@@ -29,7 +28,7 @@ class AccessKeyService(
 
     private val log = LoggerFactory.getLogger(javaClass)
 
-    @Retryable(value = [SQLException::class], maxAttempts = 5, backoff = Backoff(delay = 500L, multiplier = 1.5))
+    @Retryable(value = [SQLException::class], maxAttempts = 5, delay = 500L, multiplier = 1.5)
     @Transactional(readOnly = false, isolation = Isolation.SERIALIZABLE)
     fun validateKey(user: CmschUser, inputKey: String): AccessKeyResponse {
         val key = inputKey.trim()
diff --git a/backend/src/main/kotlin/hu/bme/sch/cmsch/component/leaderboard/LeaderBoardService.kt b/backend/src/main/kotlin/hu/bme/sch/cmsch/component/leaderboard/LeaderBoardService.kt
index b9dd7245..67a4f273 100644
--- a/backend/src/main/kotlin/hu/bme/sch/cmsch/component/leaderboard/LeaderBoardService.kt
+++ b/backend/src/main/kotlin/hu/bme/sch/cmsch/component/leaderboard/LeaderBoardService.kt
@@ -18,8 +18,7 @@ import hu.bme.sch.cmsch.util.CombinedKey
 import jakarta.annotation.PostConstruct
 import org.slf4j.LoggerFactory
 import org.springframework.boot.autoconfigure.condition.ConditionalOnBean
-import org.springframework.retry.annotation.Backoff
-import org.springframework.retry.annotation.Retryable
+import org.springframework.resilience.annotation.Retryable
 import org.springframework.scheduling.annotation.Scheduled
 import org.springframework.stereotype.Service
 import org.springframework.transaction.annotation.Isolation
@@ -135,7 +134,7 @@ open class LeaderBoardService(
         return null
     }
 
-    @Retryable(value = [ SQLException::class ], maxAttempts = 5, backoff = Backoff(delay = 500L, multiplier = 1.5))
+    @Retryable(value = [ SQLException::class ], maxAttempts = 5, delay = 500L, multiplier = 1.5)
     @Transactional(readOnly = true, isolation = Isolation.SERIALIZABLE)
     @Scheduled(fixedRate = 1000L * 60 * 60 * 10)
     open fun recalculate() {
@@ -147,7 +146,7 @@ open class LeaderBoardService(
         forceRecalculateForUsers()
     }
 
-    @Retryable(value = [ SQLException::class ], maxAttempts = 5, backoff = Backoff(delay = 500L, multiplier = 1.5))
+    @Retryable(value = [ SQLException::class ], maxAttempts = 5, delay = 500L, multiplier = 1.5)
     @Transactional(readOnly = true, isolation = Isolation.SERIALIZABLE)
     open fun forceRecalculateForGroups() {
         val hintPercentage: Float = riddleComponent.map { it.hintScorePercent }.orElse(0) / 100f
@@ -157,7 +156,7 @@ open class LeaderBoardService(
         val tasksPercent = leaderBoardComponent.tasksPercent / 100.0f
         val tasks = when (startupPropertyConfig.taskOwnershipMode) {
             OwnershipType.GROUP -> {
-                taskSubmissions.map { it.findAll() }.orElse(listOf())
+                taskSubmissions.map { it.findAll() }.orElse(mutableListOf())
                     .groupBy { CombinedKey(it.groupId ?: 0, it.groupName) }
                     .filter { groups.findByName(it.key.name).map { m -> m.races }.orElse(false) }
                     .map {
@@ -179,7 +178,7 @@ open class LeaderBoardService(
         val riddleCache = riddleRepository.map { repo -> repo.findAll().associateBy { it.id } }.orElse(mapOf())
         val riddles = when (startupPropertyConfig.riddleOwnershipMode) {
             OwnershipType.GROUP -> {
-                riddleSubmissions.map { it.findAll() }.orElse(listOf())
+                riddleSubmissions.map { it.findAll() }.orElse(mutableListOf())
                     .groupBy { groups.findById(it.ownerGroupId).orElseThrow() }
                     .filter { it.key?.races ?: false }
                     .map { riddleGroup ->
@@ -204,7 +203,7 @@ open class LeaderBoardService(
         val challengesPercent = leaderBoardComponent.challengesPercent / 100.0f
         val challenges = when (startupPropertyConfig.challengeOwnershipMode) {
             OwnershipType.GROUP -> {
-                challengeSubmissions.map { it.findAll() }.orElse(listOf())
+                challengeSubmissions.map { it.findAll() }.orElse(mutableListOf())
                     .groupBy { CombinedKey(it.groupId ?: 0, it.groupName) }
                     .filter { groups.findByName(it.key.name).map { m -> m.races }.orElse(false) }
                     .map { entity ->
@@ -255,7 +254,7 @@ open class LeaderBoardService(
                                 tokenScore = tokenScore
                             )
                         }
-                }.orElse(listOf())
+                }.orElse(mutableListOf())
             }
         }
 
@@ -282,7 +281,7 @@ open class LeaderBoardService(
         log.info("Recalculating finished")
     }
 
-    @Retryable(value = [ SQLException::class ], maxAttempts = 5, backoff = Backoff(delay = 500L, multiplier = 1.5))
+    @Retryable(value = [ SQLException::class ], maxAttempts = 5, delay = 500L, multiplier = 1.5)
     @Transactional(readOnly = true, isolation = Isolation.SERIALIZABLE)
     open fun forceRecalculateForUsers() {
         val hintPercentage: Float = riddleComponent.map { it.hintScorePercent }.orElse(0) / 100f
@@ -293,7 +292,7 @@ open class LeaderBoardService(
         val tasks = when (startupPropertyConfig.taskOwnershipMode) {
             OwnershipType.GROUP -> listOf()
             OwnershipType.USER -> {
-                taskSubmissions.map { it.findAll() }.orElse(listOf())
+                taskSubmissions.map { it.findAll() }.orElse(mutableListOf())
                     .groupBy { it.userId }
                     .map { entity ->
                         val user = users.findById(entity.key ?: 0)
@@ -316,7 +315,7 @@ open class LeaderBoardService(
         val riddles = when (startupPropertyConfig.riddleOwnershipMode) {
             OwnershipType.GROUP -> listOf()
             OwnershipType.USER -> {
-                riddleSubmissions.map { it.findAll() }.orElse(listOf())
+                riddleSubmissions.map { it.findAll() }.orElse(mutableListOf())
                     .groupBy { users.findById(it.ownerUserId).orElseThrow() }
                     .map { riddleGroup ->
                         LeaderBoardAsUserEntryDto(riddleGroup.key?.id ?: 0,
@@ -340,7 +339,7 @@ open class LeaderBoardService(
         val challenges = when (startupPropertyConfig.challengeOwnershipMode) {
             OwnershipType.GROUP -> listOf()
             OwnershipType.USER -> {
-                challengeSubmissions.map { it.findAll() }.orElse(listOf())
+                challengeSubmissions.map { it.findAll() }.orElse(mutableListOf())
                     .groupBy { it.userId }
                     .map { entity ->
                         entity.value.forEach { challenge ->
@@ -365,7 +364,7 @@ open class LeaderBoardService(
         val tokens = when (startupPropertyConfig.tokenOwnershipMode) {
             OwnershipType.GROUP -> listOf()
             OwnershipType.USER -> {
-                tokenSubmissions.map { it.findAll() }.orElse(listOf())
+                tokenSubmissions.map { it.findAll() }.orElse(mutableListOf())
                     .groupBy { it.ownerUser?.id ?: 0 }
                     .map { entity ->
                         LeaderBoardAsUserEntryDto(
diff --git a/backend/src/main/kotlin/hu/bme/sch/cmsch/component/location/LocationComponentEntityConfiguration.kt b/backend/src/main/kotlin/hu/bme/sch/cmsch/component/location/LocationComponentEntityConfiguration.kt
index daa51139..731b538f 100644
--- a/backend/src/main/kotlin/hu/bme/sch/cmsch/component/location/LocationComponentEntityConfiguration.kt
+++ b/backend/src/main/kotlin/hu/bme/sch/cmsch/component/location/LocationComponentEntityConfiguration.kt
@@ -1,7 +1,7 @@
 package hu.bme.sch.cmsch.component.location
 
 import org.springframework.boot.autoconfigure.condition.ConditionalOnBean
-import org.springframework.boot.autoconfigure.domain.EntityScan
+import org.springframework.boot.persistence.autoconfigure.EntityScan
 import org.springframework.context.annotation.Configuration
 
 @Configuration
diff --git a/backend/src/main/kotlin/hu/bme/sch/cmsch/component/location/LocationRepository.kt b/backend/src/main/kotlin/hu/bme/sch/cmsch/component/location/LocationRepository.kt
index eadc3cb6..33925511 100644
--- a/backend/src/main/kotlin/hu/bme/sch/cmsch/component/location/LocationRepository.kt
+++ b/backend/src/main/kotlin/hu/bme/sch/cmsch/component/location/LocationRepository.kt
@@ -12,5 +12,5 @@ interface LocationRepository : CrudRepository<LocationEntity, Int>,
     EntityPageDataSource<LocationEntity, Int> {
 
     fun findByUserId(userId: Int): Optional<LocationEntity>
-    override fun findAll(): List<LocationEntity>
+    override fun findAll(): MutableIterable<LocationEntity>
 }
diff --git a/backend/src/main/kotlin/hu/bme/sch/cmsch/component/location/LocationService.kt b/backend/src/main/kotlin/hu/bme/sch/cmsch/component/location/LocationService.kt
index 7793622e..db0b5645 100644
--- a/backend/src/main/kotlin/hu/bme/sch/cmsch/component/location/LocationService.kt
+++ b/backend/src/main/kotlin/hu/bme/sch/cmsch/component/location/LocationService.kt
@@ -98,9 +98,9 @@ class LocationService(
         }
     }
 
-    fun findAllLocation(): List<LocationEntity> {
+    fun findAllLocation(): MutableList<LocationEntity> {
         return tokenToLocationMapping.values.toList()
-                .sortedBy { it.groupName }
+                .sortedBy { it.groupName }.toMutableList()
     }
 
     fun clean() {
@@ -191,8 +191,8 @@ class LocationService(
 
     override fun deleteAll() = clean()
 
-    override fun <S : LocationEntity?> saveAll(entities: Iterable<S>): Iterable<S> {
-        return entities.filterNotNull().map { save(it) }
+    override fun <S : LocationEntity> saveAll(entities: MutableIterable<S>): MutableIterable<S> {
+        return entities.map { save(it) }.toMutableList()
     }
 
     override fun <S : LocationEntity> save(entity: S): S {
diff --git a/backend/src/main/kotlin/hu/bme/sch/cmsch/component/location/WaypointRepository.kt b/backend/src/main/kotlin/hu/bme/sch/cmsch/component/location/WaypointRepository.kt
index 27633800..67aab7dc 100644
--- a/backend/src/main/kotlin/hu/bme/sch/cmsch/component/location/WaypointRepository.kt
+++ b/backend/src/main/kotlin/hu/bme/sch/cmsch/component/location/WaypointRepository.kt
@@ -10,5 +10,5 @@ import org.springframework.stereotype.Repository
 interface WaypointRepository : CrudRepository<WaypointEntity, Int>,
     EntityPageDataSource<WaypointEntity, Int> {
 
-    override fun findAll(): List<WaypointEntity>
+    override fun findAll(): MutableIterable<WaypointEntity>
 }
diff --git a/backend/src/main/kotlin/hu/bme/sch/cmsch/component/news/NewsComponentEntityConfiguration.kt b/backend/src/main/kotlin/hu/bme/sch/cmsch/component/news/NewsComponentEntityConfiguration.kt
index 4ad6f6e4..5045b6b3 100644
--- a/backend/src/main/kotlin/hu/bme/sch/cmsch/component/news/NewsComponentEntityConfiguration.kt
+++ b/backend/src/main/kotlin/hu/bme/sch/cmsch/component/news/NewsComponentEntityConfiguration.kt
@@ -1,7 +1,7 @@
 package hu.bme.sch.cmsch.component.news
 
 import org.springframework.boot.autoconfigure.condition.ConditionalOnBean
-import org.springframework.boot.autoconfigure.domain.EntityScan
+import org.springframework.boot.persistence.autoconfigure.EntityScan
 import org.springframework.context.annotation.Configuration
 
 @Configuration
diff --git a/backend/src/main/kotlin/hu/bme/sch/cmsch/component/profile/ProfileService.kt b/backend/src/main/kotlin/hu/bme/sch/cmsch/component/profile/ProfileService.kt
index 9fba327c..23ec4a46 100644
--- a/backend/src/main/kotlin/hu/bme/sch/cmsch/component/profile/ProfileService.kt
+++ b/backend/src/main/kotlin/hu/bme/sch/cmsch/component/profile/ProfileService.kt
@@ -26,8 +26,7 @@ import hu.bme.sch.cmsch.service.TimeService
 import hu.bme.sch.cmsch.util.isAvailableForRole
 import hu.bme.sch.cmsch.util.mapIfTrue
 import org.springframework.boot.autoconfigure.condition.ConditionalOnBean
-import org.springframework.retry.annotation.Backoff
-import org.springframework.retry.annotation.Retryable
+import org.springframework.resilience.annotation.Retryable
 import org.springframework.stereotype.Service
 import org.springframework.transaction.annotation.Isolation
 import org.springframework.transaction.annotation.Transactional
@@ -42,14 +41,12 @@ class ProfileService(
     private val profileComponent: ProfileComponent,
     private val debtsRepository: Optional<SoldProductRepository>,
     private val locationService: Optional<LocationService>,
-    private val groupSelectionComponent: Optional<GroupSelectionComponent>,
     private val tokenService: Optional<TokenCollectorService>,
     private val tokenComponent: Optional<TokenComponent>,
     private val tasksService: Optional<TasksService>,
     private val riddleService: Optional<RiddleBusinessLogicService>,
     private val raceService: Optional<RaceService>,
     private val loginComponent: Optional<LoginComponent>,
-    private val legacyBmejegyService: Optional<LegacyBmejegyService>,
     private val clock: TimeService,
     private val startupPropertyConfig: StartupPropertyConfig,
     private val admissionService: Optional<AdmissionService>,
@@ -232,7 +229,7 @@ class ProfileService(
             .associate { Pair(it.id, it.name) }
     }
 
-    @Retryable(value = [ SQLException::class ], maxAttempts = 5, backoff = Backoff(delay = 500L, multiplier = 1.5))
+    @Retryable(value = [ SQLException::class ], maxAttempts = 5, delay = 500L, multiplier = 1.5)
     @Transactional(readOnly = false, isolation = Isolation.SERIALIZABLE)
     fun changeAlias(user: UserEntity, newAlias: String): Boolean {
         return if (newAlias.matches(Regex(profileComponent.aliasRegex))) {
diff --git a/backend/src/main/kotlin/hu/bme/sch/cmsch/component/proto/ProtoComponentEntityConfiguration.kt b/backend/src/main/kotlin/hu/bme/sch/cmsch/component/proto/ProtoComponentEntityConfiguration.kt
index a43d5220..124eaa71 100644
--- a/backend/src/main/kotlin/hu/bme/sch/cmsch/component/proto/ProtoComponentEntityConfiguration.kt
+++ b/backend/src/main/kotlin/hu/bme/sch/cmsch/component/proto/ProtoComponentEntityConfiguration.kt
@@ -1,7 +1,7 @@
 package hu.bme.sch.cmsch.component.proto
 
 import org.springframework.boot.autoconfigure.condition.ConditionalOnBean
-import org.springframework.boot.autoconfigure.domain.EntityScan
+import org.springframework.boot.persistence.autoconfigure.EntityScan
 import org.springframework.context.annotation.Configuration
 
 @Configuration
diff --git a/backend/src/main/kotlin/hu/bme/sch/cmsch/component/pushnotification/FirebaseMessagingConfiguration.kt b/backend/src/main/kotlin/hu/bme/sch/cmsch/component/pushnotification/FirebaseMessagingConfiguration.kt
index 56bd5d94..c19d97a6 100644
--- a/backend/src/main/kotlin/hu/bme/sch/cmsch/component/pushnotification/FirebaseMessagingConfiguration.kt
+++ b/backend/src/main/kotlin/hu/bme/sch/cmsch/component/pushnotification/FirebaseMessagingConfiguration.kt
@@ -8,9 +8,9 @@ import org.springframework.beans.factory.annotation.Value
 import org.springframework.boot.autoconfigure.condition.ConditionalOnBean
 import org.springframework.context.annotation.Bean
 import org.springframework.context.annotation.Configuration
-import org.springframework.retry.backoff.BackOffPolicyBuilder
-import org.springframework.retry.policy.SimpleRetryPolicy
-import org.springframework.retry.support.RetryTemplate
+import org.springframework.core.retry.RetryPolicy
+import org.springframework.core.retry.RetryTemplate
+import java.time.Duration
 
 @Configuration
 @ConditionalOnBean(PushNotificationComponent::class)
@@ -47,15 +47,14 @@ class FirebaseMessagingConfiguration {
     @Bean
     @ConditionalOnBean(PushNotificationComponent::class)
     fun retryTemplate(): RetryTemplate {
-        val retryPolicy = SimpleRetryPolicy(5)
-        val backOffPolicy = BackOffPolicyBuilder.newBuilder()
-            .delay(500L)
+        val retryPolicy = RetryPolicy.builder()
+            .maxAttempts(5)
+            .delay(Duration.ofMillis(500))
             .multiplier(1.5)
             .build()
 
         val template = RetryTemplate()
         template.setRetryPolicy(retryPolicy)
-        template.setBackOffPolicy(backOffPolicy)
         return template
     }
 }
diff --git a/backend/src/main/kotlin/hu/bme/sch/cmsch/component/pushnotification/PushNotificationComponentEntityConfiguration.kt b/backend/src/main/kotlin/hu/bme/sch/cmsch/component/pushnotification/PushNotificationComponentEntityConfiguration.kt
index c3f3c9fc..4ef337c7 100644
--- a/backend/src/main/kotlin/hu/bme/sch/cmsch/component/pushnotification/PushNotificationComponentEntityConfiguration.kt
+++ b/backend/src/main/kotlin/hu/bme/sch/cmsch/component/pushnotification/PushNotificationComponentEntityConfiguration.kt
@@ -1,7 +1,7 @@
 package hu.bme.sch.cmsch.component.pushnotification
 
 import org.springframework.boot.autoconfigure.condition.ConditionalOnBean
-import org.springframework.boot.autoconfigure.domain.EntityScan
+import org.springframework.boot.persistence.autoconfigure.EntityScan
 import org.springframework.context.annotation.Configuration
 
 @Configuration
diff --git a/backend/src/main/kotlin/hu/bme/sch/cmsch/component/pushnotification/PushNotificationService.kt b/backend/src/main/kotlin/hu/bme/sch/cmsch/component/pushnotification/PushNotificationService.kt
index de67b638..473f1ec4 100644
--- a/backend/src/main/kotlin/hu/bme/sch/cmsch/component/pushnotification/PushNotificationService.kt
+++ b/backend/src/main/kotlin/hu/bme/sch/cmsch/component/pushnotification/PushNotificationService.kt
@@ -6,7 +6,7 @@ import hu.bme.sch.cmsch.dto.CmschNotification
 import hu.bme.sch.cmsch.model.RoleType
 import org.slf4j.LoggerFactory
 import org.springframework.boot.autoconfigure.condition.ConditionalOnBean
-import org.springframework.retry.support.RetryTemplate
+import org.springframework.core.retry.RetryTemplate
 import org.springframework.stereotype.Service
 import org.springframework.transaction.annotation.Isolation
 import org.springframework.transaction.annotation.Transactional
@@ -53,7 +53,7 @@ class PushNotificationService(
 
         var tokensRemaining = tokens
         val sendResult = runCatching {
-            retryTemplate.execute<Unit, Exception> {
+            retryTemplate.execute {
                 log.debug("Attempting notification broadcast to {} devices...", tokensRemaining.size)
 
                 // The token limit per multicast message is 500
diff --git a/backend/src/main/kotlin/hu/bme/sch/cmsch/component/qrfight/QrFightComponentEntityConfiguration.kt b/backend/src/main/kotlin/hu/bme/sch/cmsch/component/qrfight/QrFightComponentEntityConfiguration.kt
index 6a4d9114..91f8de93 100644
--- a/backend/src/main/kotlin/hu/bme/sch/cmsch/component/qrfight/QrFightComponentEntityConfiguration.kt
+++ b/backend/src/main/kotlin/hu/bme/sch/cmsch/component/qrfight/QrFightComponentEntityConfiguration.kt
@@ -1,7 +1,7 @@
 package hu.bme.sch.cmsch.component.qrfight
 
 import org.springframework.boot.autoconfigure.condition.ConditionalOnBean
-import org.springframework.boot.autoconfigure.domain.EntityScan
+import org.springframework.boot.persistence.autoconfigure.EntityScan
 import org.springframework.context.annotation.Configuration
 
 @Configuration
diff --git a/backend/src/main/kotlin/hu/bme/sch/cmsch/component/qrfight/QrFightService.kt b/backend/src/main/kotlin/hu/bme/sch/cmsch/component/qrfight/QrFightService.kt
index a6c6ded6..478487f2 100644
--- a/backend/src/main/kotlin/hu/bme/sch/cmsch/component/qrfight/QrFightService.kt
+++ b/backend/src/main/kotlin/hu/bme/sch/cmsch/component/qrfight/QrFightService.kt
@@ -15,8 +15,7 @@ import hu.bme.sch.cmsch.repository.UserRepository
 import hu.bme.sch.cmsch.service.TimeService
 import org.slf4j.LoggerFactory
 import org.springframework.boot.autoconfigure.condition.ConditionalOnBean
-import org.springframework.retry.annotation.Backoff
-import org.springframework.retry.annotation.Retryable
+import org.springframework.resilience.annotation.Retryable
 import org.springframework.stereotype.Service
 import org.springframework.transaction.annotation.Isolation
 import org.springframework.transaction.annotation.Transactional
@@ -613,7 +612,7 @@ class QrFightService(
         return completedTokens >= level.minAmountToComplete
     }
 
-    @Retryable(value = [ SQLException::class ], maxAttempts = 5, backoff = Backoff(delay = 500L, multiplier = 1.5))
+    @Retryable(value = [ SQLException::class ], maxAttempts = 5, delay = 500L, multiplier = 1.5)
     @Transactional(readOnly = false, isolation = Isolation.SERIALIZABLE)
     fun executeTowerTimer() {
         log.info("Tower time!")
@@ -632,7 +631,7 @@ class QrFightService(
                     tower.holder = state.entries.filter { it.key.isNotBlank() }.maxByOrNull { it.value }?.key ?: "0"
                     tower.holderFor = (state.filter { it.key.isNotBlank() }.maxOfOrNull { it.value } ?: 0) * TIMER_OCCURRENCE
                     tower
-                }
+                }.toMutableList()
                 qrTowerRepository.saveAll(updated)
                 log.info("Tower for USER timer executed, and updated {}/{} towers", updated.size, towers.size)
             }
@@ -646,7 +645,7 @@ class QrFightService(
                     tower.holder = state.entries.filter { it.key.isNotBlank() }.maxByOrNull { it.value }?.key ?: ""
                     tower.holderFor = (state.filter { it.key.isNotBlank() }.maxOfOrNull { it.value } ?: 0) * TIMER_OCCURRENCE
                     tower
-                }
+                }.toMutableList()
                 qrTowerRepository.saveAll(updated)
                 log.info("Tower for GROUP timer executed, and updated {}/{} towers", updated.size, towers.size)
             }
diff --git a/backend/src/main/kotlin/hu/bme/sch/cmsch/component/qrfight/QrLevelRepository.kt b/backend/src/main/kotlin/hu/bme/sch/cmsch/component/qrfight/QrLevelRepository.kt
index 1bb78f24..b810f521 100644
--- a/backend/src/main/kotlin/hu/bme/sch/cmsch/component/qrfight/QrLevelRepository.kt
+++ b/backend/src/main/kotlin/hu/bme/sch/cmsch/component/qrfight/QrLevelRepository.kt
@@ -10,7 +10,7 @@ import org.springframework.stereotype.Repository
 interface QrLevelRepository : CrudRepository<QrLevelEntity, Int>,
     EntityPageDataSource<QrLevelEntity, Int> {
 
-    override fun findAll(): List<QrLevelEntity>
+    override fun findAll(): MutableIterable<QrLevelEntity>
     fun findAllByCategory(category: String): List<QrLevelEntity>
     fun findAllByVisibleTrueAndEnabledTrue(): List<QrLevelEntity>
 }
diff --git a/backend/src/main/kotlin/hu/bme/sch/cmsch/component/qrfight/QrTowerRepository.kt b/backend/src/main/kotlin/hu/bme/sch/cmsch/component/qrfight/QrTowerRepository.kt
index 69fe8063..f7061975 100644
--- a/backend/src/main/kotlin/hu/bme/sch/cmsch/component/qrfight/QrTowerRepository.kt
+++ b/backend/src/main/kotlin/hu/bme/sch/cmsch/component/qrfight/QrTowerRepository.kt
@@ -10,7 +10,7 @@ import org.springframework.stereotype.Repository
 interface QrTowerRepository : CrudRepository<QrTowerEntity, Int>,
     EntityPageDataSource<QrTowerEntity, Int> {
 
-    override fun findAll(): List<QrTowerEntity>
+    override fun findAll(): MutableIterable<QrTowerEntity>
     fun findAllBySelector(selector: String): List<QrTowerEntity>
     fun findAllByCategory(category: String): List<QrTowerEntity>
     fun findAllByRecordTimeTrue(): List<QrTowerEntity>
diff --git a/backend/src/main/kotlin/hu/bme/sch/cmsch/component/race/FreestyleRaceRecordRepository.kt b/backend/src/main/kotlin/hu/bme/sch/cmsch/component/race/FreestyleRaceRecordRepository.kt
index 11f56841..17e634ce 100644
--- a/backend/src/main/kotlin/hu/bme/sch/cmsch/component/race/FreestyleRaceRecordRepository.kt
+++ b/backend/src/main/kotlin/hu/bme/sch/cmsch/component/race/FreestyleRaceRecordRepository.kt
@@ -10,7 +10,7 @@ import org.springframework.stereotype.Repository
 interface FreestyleRaceRecordRepository : CrudRepository<FreestyleRaceRecordEntity, Int>,
     EntityPageDataSource<FreestyleRaceRecordEntity, Int> {
 
-    override fun findAll(): List<FreestyleRaceRecordEntity>
+    override fun findAll(): MutableIterable<FreestyleRaceRecordEntity>
 
     fun findByUserId(userId: Int): FreestyleRaceRecordEntity?
 }
diff --git a/backend/src/main/kotlin/hu/bme/sch/cmsch/component/race/RaceCategoryRepository.kt b/backend/src/main/kotlin/hu/bme/sch/cmsch/component/race/RaceCategoryRepository.kt
index a2f6bcb4..04e4b3b4 100644
--- a/backend/src/main/kotlin/hu/bme/sch/cmsch/component/race/RaceCategoryRepository.kt
+++ b/backend/src/main/kotlin/hu/bme/sch/cmsch/component/race/RaceCategoryRepository.kt
@@ -11,7 +11,7 @@ import java.util.*
 interface RaceCategoryRepository : CrudRepository<RaceCategoryEntity, Int>,
     EntityPageDataSource<RaceCategoryEntity, Int> {
 
-    override fun findAll(): List<RaceCategoryEntity>
+    override fun findAll(): MutableIterable<RaceCategoryEntity>
     fun findByVisibleTrueAndSlug(category: String): Optional<RaceCategoryEntity>
     override fun findById(id: Int): Optional<RaceCategoryEntity>
     fun findAllByVisibleTrue(): List<RaceCategoryEntity>
diff --git a/backend/src/main/kotlin/hu/bme/sch/cmsch/component/race/RaceComponentEntityConfiguration.kt b/backend/src/main/kotlin/hu/bme/sch/cmsch/component/race/RaceComponentEntityConfiguration.kt
index 6270e60e..1b9bfb13 100644
--- a/backend/src/main/kotlin/hu/bme/sch/cmsch/component/race/RaceComponentEntityConfiguration.kt
+++ b/backend/src/main/kotlin/hu/bme/sch/cmsch/component/race/RaceComponentEntityConfiguration.kt
@@ -1,7 +1,7 @@
 package hu.bme.sch.cmsch.component.race
 
 import org.springframework.boot.autoconfigure.condition.ConditionalOnBean
-import org.springframework.boot.autoconfigure.domain.EntityScan
+import org.springframework.boot.persistence.autoconfigure.EntityScan
 import org.springframework.context.annotation.Configuration
 
 @Configuration
diff --git a/backend/src/main/kotlin/hu/bme/sch/cmsch/component/race/RaceLeaderBoardController.kt b/backend/src/main/kotlin/hu/bme/sch/cmsch/component/race/RaceLeaderBoardController.kt
index 537835b0..1916dafc 100644
--- a/backend/src/main/kotlin/hu/bme/sch/cmsch/component/race/RaceLeaderBoardController.kt
+++ b/backend/src/main/kotlin/hu/bme/sch/cmsch/component/race/RaceLeaderBoardController.kt
@@ -37,11 +37,11 @@ class RaceLeaderBoardController(
     transactionManager,
     object : ManualRepository<RaceEntryDto, Int>() {
 
-        override fun findAll(): Iterable<RaceEntryDto> {
+        override fun findAll(): MutableList<RaceEntryDto> {
             return when (startupPropertyConfig.raceOwnershipMode) {
                 OwnershipType.USER -> raceService.getBoardForUsers(DEFAULT_CATEGORY, true)
                 OwnershipType.GROUP -> raceService.getBoardForGroups(DEFAULT_CATEGORY)
-            }
+            }.toMutableList()
         }
 
         override fun count() = findAll().count().toLong()
diff --git a/backend/src/main/kotlin/hu/bme/sch/cmsch/component/race/RaceRecordRepository.kt b/backend/src/main/kotlin/hu/bme/sch/cmsch/component/race/RaceRecordRepository.kt
index 6e88a754..4064f2ae 100644
--- a/backend/src/main/kotlin/hu/bme/sch/cmsch/component/race/RaceRecordRepository.kt
+++ b/backend/src/main/kotlin/hu/bme/sch/cmsch/component/race/RaceRecordRepository.kt
@@ -10,7 +10,7 @@ import org.springframework.stereotype.Repository
 interface RaceRecordRepository : CrudRepository<RaceRecordEntity, Int>,
     EntityPageDataSource<RaceRecordEntity, Int> {
 
-    override fun findAll(): List<RaceRecordEntity>
+    override fun findAll(): MutableIterable<RaceRecordEntity>
 
     fun findAllByCategory(category: String): List<RaceRecordEntity>
 
diff --git a/backend/src/main/kotlin/hu/bme/sch/cmsch/component/riddle/RiddleBusinessLogicService.kt b/backend/src/main/kotlin/hu/bme/sch/cmsch/component/riddle/RiddleBusinessLogicService.kt
index dca297d5..01a6d25f 100644
--- a/backend/src/main/kotlin/hu/bme/sch/cmsch/component/riddle/RiddleBusinessLogicService.kt
+++ b/backend/src/main/kotlin/hu/bme/sch/cmsch/component/riddle/RiddleBusinessLogicService.kt
@@ -4,8 +4,7 @@ import hu.bme.sch.cmsch.component.login.CmschUser
 import hu.bme.sch.cmsch.service.TimeService
 import hu.bme.sch.cmsch.service.UserService
 import org.springframework.boot.autoconfigure.condition.ConditionalOnBean
-import org.springframework.retry.annotation.Backoff
-import org.springframework.retry.annotation.Retryable
+import org.springframework.resilience.annotation.Retryable
 import org.springframework.stereotype.Service
 import org.springframework.transaction.annotation.Isolation
 import org.springframework.transaction.annotation.Propagation
@@ -128,7 +127,7 @@ class RiddleBusinessLogicService(
         )
     }
 
-    @Retryable(value = [SQLException::class], maxAttempts = 5, backoff = Backoff(delay = 500L, multiplier = 1.5))
+    @Retryable(value = [SQLException::class], maxAttempts = 5, delay = 500L, multiplier = 1.5)
     @Transactional(readOnly = false, isolation = Isolation.SERIALIZABLE)
     override fun unlockHintForUser(user: CmschUser, riddleId: Int): String? {
         val riddle = riddleCacheManager.getRiddleById(riddleId) ?: return null
@@ -153,7 +152,7 @@ class RiddleBusinessLogicService(
         return riddle.hint
     }
 
-    @Retryable(value = [SQLException::class], maxAttempts = 5, backoff = Backoff(delay = 500L, multiplier = 1.5))
+    @Retryable(value = [SQLException::class], maxAttempts = 5, delay = 500L, multiplier = 1.5)
     @Transactional(readOnly = false, isolation = Isolation.SERIALIZABLE)
     override fun unlockHintForGroup(user: CmschUser, groupId: Int?, groupName: String, riddleId: Int): String? {
         if (groupId == null)
@@ -180,7 +179,7 @@ class RiddleBusinessLogicService(
         return riddle.hint
     }
 
-    @Retryable(value = [SQLException::class], maxAttempts = 5, backoff = Backoff(delay = 500L, multiplier = 1.5))
+    @Retryable(value = [SQLException::class], maxAttempts = 5, delay = 500L, multiplier = 1.5)
     @Transactional(readOnly = false, isolation = Isolation.SERIALIZABLE, propagation = Propagation.REQUIRES_NEW)
     override fun submitRiddleForUser(
         user: CmschUser,
@@ -257,7 +256,7 @@ class RiddleBusinessLogicService(
         }
     }
 
-    @Retryable(value = [SQLException::class], maxAttempts = 5, backoff = Backoff(delay = 500L, multiplier = 1.5))
+    @Retryable(value = [SQLException::class], maxAttempts = 5, delay = 500L, multiplier = 1.5)
     @Transactional(readOnly = false, isolation = Isolation.SERIALIZABLE, propagation = Propagation.REQUIRES_NEW)
     override fun submitRiddleForGroup(
         user: CmschUser,
diff --git a/backend/src/main/kotlin/hu/bme/sch/cmsch/component/riddle/RiddleCacheManager.kt b/backend/src/main/kotlin/hu/bme/sch/cmsch/component/riddle/RiddleCacheManager.kt
index 3156d905..6f263243 100644
--- a/backend/src/main/kotlin/hu/bme/sch/cmsch/component/riddle/RiddleCacheManager.kt
+++ b/backend/src/main/kotlin/hu/bme/sch/cmsch/component/riddle/RiddleCacheManager.kt
@@ -5,8 +5,7 @@ import hu.bme.sch.cmsch.model.RoleType
 import jakarta.annotation.PostConstruct
 import org.slf4j.LoggerFactory
 import org.springframework.boot.autoconfigure.condition.ConditionalOnBean
-import org.springframework.retry.annotation.Backoff
-import org.springframework.retry.annotation.Retryable
+import org.springframework.resilience.annotation.Retryable
 import org.springframework.scheduling.annotation.Scheduled
 import org.springframework.stereotype.Service
 import org.springframework.transaction.annotation.Isolation
@@ -59,7 +58,7 @@ class RiddleCacheManager(
         resetCache(persistMapping = false, overrideMappings = true)
     }
 
-    @Retryable(value = [ SQLException::class ], maxAttempts = 5, backoff = Backoff(delay = 500L, multiplier = 1.5))
+    @Retryable(value = [ SQLException::class ], maxAttempts = 5, delay = 500L, multiplier = 1.5)
     @Transactional(readOnly = false, isolation = Isolation.SERIALIZABLE, propagation = Propagation.REQUIRES_NEW)
     fun resetCache(persistMapping: Boolean, overrideMappings: Boolean) {
         log.info("Getting all locks for 'resetCache({}, {})'", persistMapping, overrideMappings)
diff --git a/backend/src/main/kotlin/hu/bme/sch/cmsch/component/riddle/RiddleComponentEntityConfiguration.kt b/backend/src/main/kotlin/hu/bme/sch/cmsch/component/riddle/RiddleComponentEntityConfiguration.kt
index 89827083..b5909591 100644
--- a/backend/src/main/kotlin/hu/bme/sch/cmsch/component/riddle/RiddleComponentEntityConfiguration.kt
+++ b/backend/src/main/kotlin/hu/bme/sch/cmsch/component/riddle/RiddleComponentEntityConfiguration.kt
@@ -1,7 +1,7 @@
 package hu.bme.sch.cmsch.component.riddle
 
 import org.springframework.boot.autoconfigure.condition.ConditionalOnBean
-import org.springframework.boot.autoconfigure.domain.EntityScan
+import org.springframework.boot.persistence.autoconfigure.EntityScan
 import org.springframework.context.annotation.Configuration
 
 @Configuration
diff --git a/backend/src/main/kotlin/hu/bme/sch/cmsch/component/riddle/RiddleEntityRepository.kt b/backend/src/main/kotlin/hu/bme/sch/cmsch/component/riddle/RiddleEntityRepository.kt
index f11a9254..554353ce 100644
--- a/backend/src/main/kotlin/hu/bme/sch/cmsch/component/riddle/RiddleEntityRepository.kt
+++ b/backend/src/main/kotlin/hu/bme/sch/cmsch/component/riddle/RiddleEntityRepository.kt
@@ -10,6 +10,6 @@ import org.springframework.stereotype.Repository
 interface RiddleEntityRepository : CrudRepository<RiddleEntity, Int>,
     EntityPageDataSource<RiddleEntity, Int> {
     
-    override fun findAll(): List<RiddleEntity>
+    override fun findAll(): MutableIterable<RiddleEntity>
 
 }
diff --git a/backend/src/main/kotlin/hu/bme/sch/cmsch/component/riddle/RiddlePersistenceService.kt b/backend/src/main/kotlin/hu/bme/sch/cmsch/component/riddle/RiddlePersistenceService.kt
index 97c43f32..0fe816b2 100644
--- a/backend/src/main/kotlin/hu/bme/sch/cmsch/component/riddle/RiddlePersistenceService.kt
+++ b/backend/src/main/kotlin/hu/bme/sch/cmsch/component/riddle/RiddlePersistenceService.kt
@@ -1,8 +1,7 @@
 package hu.bme.sch.cmsch.component.riddle
 
 import org.springframework.boot.autoconfigure.condition.ConditionalOnBean
-import org.springframework.retry.annotation.Backoff
-import org.springframework.retry.annotation.Retryable
+import org.springframework.resilience.annotation.Retryable
 import org.springframework.stereotype.Service
 import org.springframework.transaction.annotation.Isolation
 import org.springframework.transaction.annotation.Propagation
@@ -16,7 +15,7 @@ class RiddlePersistenceService(
     private val riddleMappingRepository: RiddleMappingRepository,
 ) {
 
-    @Retryable(value = [ SQLException::class ], maxAttempts = 5, backoff = Backoff(delay = 500L, multiplier = 1.5))
+    @Retryable(value = [ SQLException::class ], maxAttempts = 5, delay = 500L, multiplier = 1.5)
     @Transactional(readOnly = false, isolation = Isolation.SERIALIZABLE, propagation = Propagation.REQUIRES_NEW)
     fun saveAllRiddleMapping(entities: MutableIterable<RiddleMappingEntity>) {
         riddleMappingRepository.saveAll(entities)
diff --git a/backend/src/main/kotlin/hu/bme/sch/cmsch/component/riddle/RiddlesByGroupsController.kt b/backend/src/main/kotlin/hu/bme/sch/cmsch/component/riddle/RiddlesByGroupsController.kt
index ae8524d5..7626ec7e 100644
--- a/backend/src/main/kotlin/hu/bme/sch/cmsch/component/riddle/RiddlesByGroupsController.kt
+++ b/backend/src/main/kotlin/hu/bme/sch/cmsch/component/riddle/RiddlesByGroupsController.kt
@@ -47,7 +47,7 @@ class RiddlesByGroupsController(
 
     transactionManager,
     object : ManualRepository<RiddleStatsVirtualEntity, Int>() {
-        override fun findAll(): Iterable<RiddleStatsVirtualEntity> {
+        override fun findAll(): MutableIterable<RiddleStatsVirtualEntity> {
             return transactionManager.transaction(readOnly = true) { riddleMappingRepository.findAll() }
                 .groupBy { it.ownerGroupId }
                 .map { it.value }
@@ -60,7 +60,7 @@ class RiddlesByGroupsController(
                         submissions.count { it.completed },
                         submissions.count { it.hintUsed }
                     )
-                }
+                }.toMutableList()
         }
 
         override fun delete(entity: RiddleStatsVirtualEntity) {
diff --git a/backend/src/main/kotlin/hu/bme/sch/cmsch/component/riddle/RiddlesByUsersController.kt b/backend/src/main/kotlin/hu/bme/sch/cmsch/component/riddle/RiddlesByUsersController.kt
index 7c3cbc85..02e52c98 100644
--- a/backend/src/main/kotlin/hu/bme/sch/cmsch/component/riddle/RiddlesByUsersController.kt
+++ b/backend/src/main/kotlin/hu/bme/sch/cmsch/component/riddle/RiddlesByUsersController.kt
@@ -37,7 +37,7 @@ class RiddlesByUsersController(
 
     transactionManager,
     object : ManualRepository<RiddleStatsVirtualEntity, Int>() {
-        override fun findAll(): Iterable<RiddleStatsVirtualEntity> {
+        override fun findAll(): MutableIterable<RiddleStatsVirtualEntity> {
             return transactionManager.transaction(readOnly = true) { riddleMappingRepository.findAll() }
                 .groupBy { it.ownerUserId }
                 .map { it.value }
@@ -50,7 +50,7 @@ class RiddlesByUsersController(
                         submissions.count { it.completed },
                         submissions.count { it.hintUsed }
                     )
-                }
+                }.toMutableList()
         }
 
         override fun delete(entity: RiddleStatsVirtualEntity) {
diff --git a/backend/src/main/kotlin/hu/bme/sch/cmsch/component/script/ScriptComponentEntityConfiguration.kt b/backend/src/main/kotlin/hu/bme/sch/cmsch/component/script/ScriptComponentEntityConfiguration.kt
index 3c56129d..47a83672 100644
--- a/backend/src/main/kotlin/hu/bme/sch/cmsch/component/script/ScriptComponentEntityConfiguration.kt
+++ b/backend/src/main/kotlin/hu/bme/sch/cmsch/component/script/ScriptComponentEntityConfiguration.kt
@@ -1,7 +1,7 @@
 package hu.bme.sch.cmsch.component.script
 
 import org.springframework.boot.autoconfigure.condition.ConditionalOnBean
-import org.springframework.boot.autoconfigure.domain.EntityScan
+import org.springframework.boot.persistence.autoconfigure.EntityScan
 import org.springframework.context.annotation.Configuration
 
 @Configuration
diff --git a/backend/src/main/kotlin/hu/bme/sch/cmsch/component/script/ScriptRunnerDashboard.kt b/backend/src/main/kotlin/hu/bme/sch/cmsch/component/script/ScriptRunnerDashboard.kt
index ba908c19..426dfb17 100644
--- a/backend/src/main/kotlin/hu/bme/sch/cmsch/component/script/ScriptRunnerDashboard.kt
+++ b/backend/src/main/kotlin/hu/bme/sch/cmsch/component/script/ScriptRunnerDashboard.kt
@@ -52,7 +52,7 @@ class ScriptRunnerDashboard(
     ignoreFromMenu = true
 ) {
 
-    private final val log = LoggerFactory.getLogger(javaClass)
+    private val log = LoggerFactory.getLogger(javaClass)
 
     override fun getComponents(user: CmschUser, requestParams: Map<String, String>): List<DashboardComponent> {
         return listOf()
diff --git a/backend/src/main/kotlin/hu/bme/sch/cmsch/component/script/ScriptService.kt b/backend/src/main/kotlin/hu/bme/sch/cmsch/component/script/ScriptService.kt
index 0c0175e4..89dbcdf2 100644
--- a/backend/src/main/kotlin/hu/bme/sch/cmsch/component/script/ScriptService.kt
+++ b/backend/src/main/kotlin/hu/bme/sch/cmsch/component/script/ScriptService.kt
@@ -31,7 +31,7 @@ class ScriptService(
     private val transactionManager: PlatformTransactionManager
 ) {
 
-    private final val log = LoggerFactory.getLogger(javaClass)
+    private val log = LoggerFactory.getLogger(javaClass)
 
     private final val objectMapper = jacksonObjectMapper()
     private final val artifactWriter = objectMapper.writerFor(object : TypeReference<List<ScriptArtifact>>() {})
diff --git a/backend/src/main/kotlin/hu/bme/sch/cmsch/component/script/sandbox/ScriptingContext.kt b/backend/src/main/kotlin/hu/bme/sch/cmsch/component/script/sandbox/ScriptingContext.kt
index 98d7ad10..eefc2ec9 100644
--- a/backend/src/main/kotlin/hu/bme/sch/cmsch/component/script/sandbox/ScriptingContext.kt
+++ b/backend/src/main/kotlin/hu/bme/sch/cmsch/component/script/sandbox/ScriptingContext.kt
@@ -134,7 +134,7 @@ class ReadOnlyScriptingDbContext(private val supportedRepos: List<CrudRepository
 class ReadOnlyRepositoryProxy<T : Duplicatable, ID : Any>(private val proxy: CrudRepository<T, ID>) {
 
     fun findAll(): List<T> {
-        return proxy.findAll().mapNotNull { if (it is T) { it.duplicate() as T } else null }.toList()
+        return proxy.findAll().mapNotNull { it.duplicate() as T }.toList()
     }
 
     fun findById(id: ID): T? {
@@ -159,4 +159,4 @@ class ModifyingScriptingComponentContext(
             ?: error("Cannot find component for $selectedComponent")
     }
 
-}
\ No newline at end of file
+}
diff --git a/backend/src/main/kotlin/hu/bme/sch/cmsch/component/serviceaccount/ServiceAccountComponentConfiguration.kt b/backend/src/main/kotlin/hu/bme/sch/cmsch/component/serviceaccount/ServiceAccountComponentConfiguration.kt
index 50da1793..db723a3b 100644
--- a/backend/src/main/kotlin/hu/bme/sch/cmsch/component/serviceaccount/ServiceAccountComponentConfiguration.kt
+++ b/backend/src/main/kotlin/hu/bme/sch/cmsch/component/serviceaccount/ServiceAccountComponentConfiguration.kt
@@ -1,7 +1,7 @@
 package hu.bme.sch.cmsch.component.serviceaccount
 
 import org.springframework.boot.autoconfigure.condition.ConditionalOnBean
-import org.springframework.boot.autoconfigure.domain.EntityScan
+import org.springframework.boot.persistence.autoconfigure.EntityScan
 import org.springframework.context.annotation.Configuration
 
 @Configuration
diff --git a/backend/src/main/kotlin/hu/bme/sch/cmsch/component/sheets/SheetsComponentEntityConfiguration.kt b/backend/src/main/kotlin/hu/bme/sch/cmsch/component/sheets/SheetsComponentEntityConfiguration.kt
index ea79f32a..d92611bf 100644
--- a/backend/src/main/kotlin/hu/bme/sch/cmsch/component/sheets/SheetsComponentEntityConfiguration.kt
+++ b/backend/src/main/kotlin/hu/bme/sch/cmsch/component/sheets/SheetsComponentEntityConfiguration.kt
@@ -1,10 +1,10 @@
 package hu.bme.sch.cmsch.component.sheets
 
 import org.springframework.boot.autoconfigure.condition.ConditionalOnBean
-import org.springframework.boot.autoconfigure.domain.EntityScan
+import org.springframework.boot.persistence.autoconfigure.EntityScan
 import org.springframework.context.annotation.Configuration
 
 @Configuration
 @ConditionalOnBean(SheetsComponent::class)
 @EntityScan(basePackageClasses = [SheetsComponent::class])
-class SheetsComponentEntityConfiguration
\ No newline at end of file
+class SheetsComponentEntityConfiguration
diff --git a/backend/src/main/kotlin/hu/bme/sch/cmsch/component/sheets/SheetsUpdaterService.kt b/backend/src/main/kotlin/hu/bme/sch/cmsch/component/sheets/SheetsUpdaterService.kt
index e5feec98..2208ebd4 100644
--- a/backend/src/main/kotlin/hu/bme/sch/cmsch/component/sheets/SheetsUpdaterService.kt
+++ b/backend/src/main/kotlin/hu/bme/sch/cmsch/component/sheets/SheetsUpdaterService.kt
@@ -30,7 +30,7 @@ class SheetsUpdaterService(
     private val responseRepository: ResponseRepository
 ) {
 
-    private final val log = LoggerFactory.getLogger(javaClass)
+    private val log = LoggerFactory.getLogger(javaClass)
     private final val objectMapper = jacksonObjectMapper()
     private final val sheetsUpdateRequestWriter = objectMapper.writerFor(SheetsUpdateRequest::class.java)
     private final val sheetsUpdateResponseReader = objectMapper.readerFor(SheetsUpdateResponse::class.java)
diff --git a/backend/src/main/kotlin/hu/bme/sch/cmsch/component/staticpage/StaticPageComponentEntityConfiguration.kt b/backend/src/main/kotlin/hu/bme/sch/cmsch/component/staticpage/StaticPageComponentEntityConfiguration.kt
index b45de957..ed8dd332 100644
--- a/backend/src/main/kotlin/hu/bme/sch/cmsch/component/staticpage/StaticPageComponentEntityConfiguration.kt
+++ b/backend/src/main/kotlin/hu/bme/sch/cmsch/component/staticpage/StaticPageComponentEntityConfiguration.kt
@@ -1,7 +1,7 @@
 package hu.bme.sch.cmsch.component.staticpage
 
 import org.springframework.boot.autoconfigure.condition.ConditionalOnBean
-import org.springframework.boot.autoconfigure.domain.EntityScan
+import org.springframework.boot.persistence.autoconfigure.EntityScan
 import org.springframework.context.annotation.Configuration
 
 @Configuration
diff --git a/backend/src/main/kotlin/hu/bme/sch/cmsch/component/task/TaskAdminRateController.kt b/backend/src/main/kotlin/hu/bme/sch/cmsch/component/task/TaskAdminRateController.kt
index 943d5cd5..29630617 100644
--- a/backend/src/main/kotlin/hu/bme/sch/cmsch/component/task/TaskAdminRateController.kt
+++ b/backend/src/main/kotlin/hu/bme/sch/cmsch/component/task/TaskAdminRateController.kt
@@ -42,7 +42,7 @@ class TaskAdminRateController(
 
     transactionManager,
     object : ManualRepository<GradedTaskGroupDto, Int>() {
-        override fun findAll(): Iterable<GradedTaskGroupDto> {
+        override fun findAll(): MutableIterable<GradedTaskGroupDto> {
             val aggregatedResults = submittedRepository.findAllAggregated()
 
             return aggregatedResults.map {
@@ -53,7 +53,7 @@ class TaskAdminRateController(
                     it.rejectedCount.toInt(),
                     it.notGradedCount.toInt()
                 )
-            }.sortedByDescending { it.notGraded }.toList()
+            }.sortedByDescending { it.notGraded }.toMutableList()
         }
     },
     submittedRepository,
diff --git a/backend/src/main/kotlin/hu/bme/sch/cmsch/component/task/TaskCategoryRepository.kt b/backend/src/main/kotlin/hu/bme/sch/cmsch/component/task/TaskCategoryRepository.kt
index c3497f60..c5bf953d 100644
--- a/backend/src/main/kotlin/hu/bme/sch/cmsch/component/task/TaskCategoryRepository.kt
+++ b/backend/src/main/kotlin/hu/bme/sch/cmsch/component/task/TaskCategoryRepository.kt
@@ -10,7 +10,7 @@ import org.springframework.stereotype.Repository
 interface TaskCategoryRepository : CrudRepository<TaskCategoryEntity, Int>,
     EntityPageDataSource<TaskCategoryEntity, Int> {
 
-    override fun findAll(): List<TaskCategoryEntity>
+    override fun findAll(): MutableIterable<TaskCategoryEntity>
     fun findAllByAvailableFromLessThanAndAvailableToGreaterThan(availableFrom: Long, availableTo: Long): List<TaskCategoryEntity>
     fun findAllByCategoryId(categoryId: Int): List<TaskCategoryEntity>
     fun findAllByType(type: TaskCategoryType): List<TaskCategoryEntity>
diff --git a/backend/src/main/kotlin/hu/bme/sch/cmsch/component/task/TaskComponentEntityConfiguration.kt b/backend/src/main/kotlin/hu/bme/sch/cmsch/component/task/TaskComponentEntityConfiguration.kt
index c1d14664..1577081a 100644
--- a/backend/src/main/kotlin/hu/bme/sch/cmsch/component/task/TaskComponentEntityConfiguration.kt
+++ b/backend/src/main/kotlin/hu/bme/sch/cmsch/component/task/TaskComponentEntityConfiguration.kt
@@ -1,7 +1,7 @@
 package hu.bme.sch.cmsch.component.task
 
 import org.springframework.boot.autoconfigure.condition.ConditionalOnBean
-import org.springframework.boot.autoconfigure.domain.EntityScan
+import org.springframework.boot.persistence.autoconfigure.EntityScan
 import org.springframework.context.annotation.Configuration
 
 @Configuration
diff --git a/backend/src/main/kotlin/hu/bme/sch/cmsch/component/task/TasksService.kt b/backend/src/main/kotlin/hu/bme/sch/cmsch/component/task/TasksService.kt
index 3ea66506..4cbeac1c 100644
--- a/backend/src/main/kotlin/hu/bme/sch/cmsch/component/task/TasksService.kt
+++ b/backend/src/main/kotlin/hu/bme/sch/cmsch/component/task/TasksService.kt
@@ -10,8 +10,7 @@ import hu.bme.sch.cmsch.service.StorageService
 import hu.bme.sch.cmsch.service.TimeService
 import org.slf4j.LoggerFactory
 import org.springframework.boot.autoconfigure.condition.ConditionalOnBean
-import org.springframework.retry.annotation.Backoff
-import org.springframework.retry.annotation.Retryable
+import org.springframework.resilience.annotation.Retryable
 import org.springframework.stereotype.Service
 import org.springframework.transaction.annotation.Isolation
 import org.springframework.transaction.annotation.Transactional
@@ -117,7 +116,7 @@ class TasksService(
         }
     }
 
-    @Retryable(value = [ SQLException::class ], maxAttempts = 5, backoff = Backoff(delay = 500L, multiplier = 1.5))
+    @Retryable(value = [ SQLException::class ], maxAttempts = 5, delay = 500L, multiplier = 1.5)
     @Transactional(readOnly = false, isolation = Isolation.SERIALIZABLE)
     fun submitTaskReview(
         taskId: Int,
@@ -173,7 +172,7 @@ class TasksService(
         return true
     }
 
-    @Retryable(value = [ SQLException::class ], maxAttempts = 5, backoff = Backoff(delay = 500L, multiplier = 1.5))
+    @Retryable(value = [ SQLException::class ], maxAttempts = 5, delay = 500L, multiplier = 1.5)
     @Transactional(readOnly = false, isolation = Isolation.SERIALIZABLE)
     fun submitTaskForGroup(answer: TaskSubmissionDto, file: MultipartFile?, user: CmschUser): TaskSubmissionStatus {
         val groupId = user.groupId
diff --git a/backend/src/main/kotlin/hu/bme/sch/cmsch/component/team/TeamComponentEntityConfiguration.kt b/backend/src/main/kotlin/hu/bme/sch/cmsch/component/team/TeamComponentEntityConfiguration.kt
index f682a958..f0dfafa7 100644
--- a/backend/src/main/kotlin/hu/bme/sch/cmsch/component/team/TeamComponentEntityConfiguration.kt
+++ b/backend/src/main/kotlin/hu/bme/sch/cmsch/component/team/TeamComponentEntityConfiguration.kt
@@ -1,6 +1,6 @@
 package hu.bme.sch.cmsch.component.team
 
-import org.springframework.boot.autoconfigure.domain.EntityScan
+import org.springframework.boot.persistence.autoconfigure.EntityScan
 import org.springframework.context.annotation.Configuration
 
 @Configuration
diff --git a/backend/src/main/kotlin/hu/bme/sch/cmsch/component/team/TeamService.kt b/backend/src/main/kotlin/hu/bme/sch/cmsch/component/team/TeamService.kt
index 28646d34..2da08c2d 100644
--- a/backend/src/main/kotlin/hu/bme/sch/cmsch/component/team/TeamService.kt
+++ b/backend/src/main/kotlin/hu/bme/sch/cmsch/component/team/TeamService.kt
@@ -20,8 +20,7 @@ import hu.bme.sch.cmsch.service.StorageService
 import hu.bme.sch.cmsch.service.TimeService
 import org.slf4j.LoggerFactory
 import org.springframework.boot.autoconfigure.condition.ConditionalOnBean
-import org.springframework.retry.annotation.Backoff
-import org.springframework.retry.annotation.Retryable
+import org.springframework.resilience.annotation.Retryable
 import org.springframework.stereotype.Service
 import org.springframework.transaction.annotation.Isolation
 import org.springframework.transaction.annotation.Transactional
@@ -57,7 +56,7 @@ class TeamService(
 
     private val log = LoggerFactory.getLogger(javaClass)
 
-    @Retryable(value = [ SQLException::class ], maxAttempts = 5, backoff = Backoff(delay = 500L, multiplier = 1.5))
+    @Retryable(value = [ SQLException::class ], maxAttempts = 5, delay = 500L, multiplier = 1.5)
     @Transactional(readOnly = false, isolation = Isolation.SERIALIZABLE)
     fun createTeam(user: UserEntity, name: String): TeamCreationStatus {
         if (user.group?.leaveable == false)
@@ -117,7 +116,7 @@ class TeamService(
         }
     }
 
-    @Retryable(value = [ SQLException::class ], maxAttempts = 5, backoff = Backoff(delay = 500L, multiplier = 1.5))
+    @Retryable(value = [ SQLException::class ], maxAttempts = 5, delay = 500L, multiplier = 1.5)
     @Transactional(readOnly = false, isolation = Isolation.SERIALIZABLE)
     fun joinTeam(user: UserEntity, groupId: Int): TeamJoinStatus {
         if (user.group?.leaveable == false)
@@ -141,7 +140,7 @@ class TeamService(
         return TeamJoinStatus.OK
     }
 
-    @Retryable(value = [ SQLException::class ], maxAttempts = 5, backoff = Backoff(delay = 500L, multiplier = 1.5))
+    @Retryable(value = [ SQLException::class ], maxAttempts = 5, delay = 500L, multiplier = 1.5)
     @Transactional(readOnly = false, isolation = Isolation.SERIALIZABLE)
     fun cancelJoin(user: CmschUser): TeamJoinStatus {
         if (!teamComponent.joinEnabled)
@@ -152,7 +151,7 @@ class TeamService(
         return TeamJoinStatus.OK
     }
 
-    @Retryable(value = [ SQLException::class ], maxAttempts = 5, backoff = Backoff(delay = 500L, multiplier = 1.5))
+    @Retryable(value = [ SQLException::class ], maxAttempts = 5, delay = 500L, multiplier = 1.5)
     @Transactional(readOnly = false, isolation = Isolation.SERIALIZABLE)
     fun leaveTeam(user: CmschUser): TeamLeaveStatus {
         if (!teamComponent.leaveEnabled)
@@ -410,7 +409,7 @@ class TeamService(
             .map { TeamMemberView(it.userName, it.userId, isAdmin = false, isYou = false) }
     }
 
-    @Retryable(value = [ SQLException::class ], maxAttempts = 5, backoff = Backoff(delay = 500L, multiplier = 1.5))
+    @Retryable(value = [ SQLException::class ], maxAttempts = 5, delay = 500L, multiplier = 1.5)
     @Transactional(readOnly = false, isolation = Isolation.SERIALIZABLE)
     fun acceptJoin(userId: Int, group: GroupEntity?): Boolean {
         if (group == null)
@@ -437,7 +436,7 @@ class TeamService(
         }
     }
 
-    @Retryable(value = [ SQLException::class ], maxAttempts = 5, backoff = Backoff(delay = 500L, multiplier = 1.5))
+    @Retryable(value = [ SQLException::class ], maxAttempts = 5, delay = 500L, multiplier = 1.5)
     @Transactional(readOnly = false, isolation = Isolation.SERIALIZABLE)
     fun rejectJoin(userId: Int, groupId: Int?, groupName: String): Boolean {
         if (groupId == null)
@@ -452,7 +451,7 @@ class TeamService(
         return false
     }
 
-    @Retryable(value = [ SQLException::class ], maxAttempts = 5, backoff = Backoff(delay = 500L, multiplier = 1.5))
+    @Retryable(value = [ SQLException::class ], maxAttempts = 5, delay = 500L, multiplier = 1.5)
     @Transactional(readOnly = false, isolation = Isolation.SERIALIZABLE)
     fun toggleUserPermissions(userId: Int, groupId: Int?, groupName: String, adminUser: CmschUser): Boolean {
         if (groupId == null)
@@ -495,7 +494,7 @@ class TeamService(
         }
     }
 
-    @Retryable(value = [ SQLException::class ], maxAttempts = 5, backoff = Backoff(delay = 500L, multiplier = 1.5))
+    @Retryable(value = [ SQLException::class ], maxAttempts = 5, delay = 500L, multiplier = 1.5)
     @Transactional(readOnly = false, isolation = Isolation.SERIALIZABLE)
     fun promoteLeader(userId: Int, groupId: Int?, groupName: String, adminUser: CmschUser): Boolean {
         if (groupId == null)
@@ -537,7 +536,7 @@ class TeamService(
         return true
     }
 
-    @Retryable(value = [ SQLException::class ], maxAttempts = 5, backoff = Backoff(delay = 500L, multiplier = 1.5))
+    @Retryable(value = [ SQLException::class ], maxAttempts = 5, delay = 500L, multiplier = 1.5)
     @Transactional(readOnly = false, isolation = Isolation.SERIALIZABLE)
     fun kickUser(userId: Int, groupId: Int?, groupName: String, adminUser: CmschUser): Boolean {
         if (groupId == null)
@@ -577,7 +576,7 @@ class TeamService(
         log.info("User '{}' kicked from '{}', reason: by admin '{}'", user.fullName, groupName, adminUser.userName)
         return true
     }
-    @Retryable(value = [ SQLException::class ], maxAttempts = 5, backoff = Backoff(delay = 500L, multiplier = 1.5))
+    @Retryable(value = [ SQLException::class ], maxAttempts = 5, delay = 500L, multiplier = 1.5)
     @Transactional(readOnly = false, isolation = Isolation.SERIALIZABLE)
     fun setDescriptionAndLogo(description: String, logo: MultipartFile?, user: CmschUser): TeamEditStatus {
         val groupId = user.groupId ?: throw IllegalStateException("The user is not member of a group yet")
diff --git a/backend/src/main/kotlin/hu/bme/sch/cmsch/component/token/BulkTokenGeneratorDashboard.kt b/backend/src/main/kotlin/hu/bme/sch/cmsch/component/token/BulkTokenGeneratorDashboard.kt
index c936ca96..90287d5a 100644
--- a/backend/src/main/kotlin/hu/bme/sch/cmsch/component/token/BulkTokenGeneratorDashboard.kt
+++ b/backend/src/main/kotlin/hu/bme/sch/cmsch/component/token/BulkTokenGeneratorDashboard.kt
@@ -155,11 +155,11 @@ class BulkTokenGeneratorDashboard(
                     availableFrom = timeService.getTimeInSeconds(),
                     availableUntil = timeService.getTimeInSeconds() + (dateUntil * 24 * 60 * 60),
                 )
-            })
+            }.toMutableList())
             return@transaction result.count()
         }
 
         return dashboardPage(VIEW, 2, "${n}db token beszúrva")
     }
 
-}
\ No newline at end of file
+}
diff --git a/backend/src/main/kotlin/hu/bme/sch/cmsch/component/token/TokenAdminTokensByGroupController.kt b/backend/src/main/kotlin/hu/bme/sch/cmsch/component/token/TokenAdminTokensByGroupController.kt
index a992a6e0..8893ffd2 100644
--- a/backend/src/main/kotlin/hu/bme/sch/cmsch/component/token/TokenAdminTokensByGroupController.kt
+++ b/backend/src/main/kotlin/hu/bme/sch/cmsch/component/token/TokenAdminTokensByGroupController.kt
@@ -41,7 +41,7 @@ class TokenAdminTokensByGroupController(
 
     transactionManager,
     object : ManualRepository<TokenListByGroupVirtualEntity, Int>() {
-        override fun findAll(): Iterable<TokenListByGroupVirtualEntity> {
+        override fun findAll(): MutableIterable<TokenListByGroupVirtualEntity> {
             return repo.findAll()
                 .groupBy { it.ownerGroup?.id ?: 0 }
                 .map { it.value }
@@ -53,7 +53,7 @@ class TokenAdminTokensByGroupController(
                         groupName,
                         token.count()
                     )
-                }
+                }.toMutableList()
         }
 
         override fun delete(entity: TokenListByGroupVirtualEntity) {
diff --git a/backend/src/main/kotlin/hu/bme/sch/cmsch/component/token/TokenAdminTokensByTeamController.kt b/backend/src/main/kotlin/hu/bme/sch/cmsch/component/token/TokenAdminTokensByTeamController.kt
index 1e33859f..853599fd 100644
--- a/backend/src/main/kotlin/hu/bme/sch/cmsch/component/token/TokenAdminTokensByTeamController.kt
+++ b/backend/src/main/kotlin/hu/bme/sch/cmsch/component/token/TokenAdminTokensByTeamController.kt
@@ -41,13 +41,13 @@ class TokenAdminTokensByTeamController(
 
     transactionManager,
     object : ManualRepository<UserGroupTokenCount, Int>() {
-        override fun findAll(): Iterable<UserGroupTokenCount> {
+        override fun findAll(): MutableIterable<UserGroupTokenCount> {
             transactionManager.transaction(readOnly = true) {
                 val data = repo.countByAllUserGroup()
                 data.forEach { it.memberCount = userRepository.findAllByGroupName(it.groupName).size }
                 val highestTeamMemberCount = data.maxByOrNull { it.correctedPoints }?.memberCount ?: 0
                 data.forEach { it.finalPoints = (it.correctedPoints * highestTeamMemberCount).toInt() }
-                return data
+                return data.toMutableList()
             }
         }
     },
diff --git a/backend/src/main/kotlin/hu/bme/sch/cmsch/component/token/TokenAdminTokensByTypeController.kt b/backend/src/main/kotlin/hu/bme/sch/cmsch/component/token/TokenAdminTokensByTypeController.kt
index 5f0d4c55..ec1c0baa 100644
--- a/backend/src/main/kotlin/hu/bme/sch/cmsch/component/token/TokenAdminTokensByTypeController.kt
+++ b/backend/src/main/kotlin/hu/bme/sch/cmsch/component/token/TokenAdminTokensByTypeController.kt
@@ -32,7 +32,7 @@ class TokenAdminTokensByTypeController(
 
     transactionManager,
     object : ManualRepository<TokenStatVirtualEntity, Int>() {
-        override fun findAll(): Iterable<TokenStatVirtualEntity> {
+        override fun findAll(): MutableIterable<TokenStatVirtualEntity> {
             return repo.findAll()
                 .groupBy { it.token?.id }
                 .map { it.value }
@@ -44,7 +44,7 @@ class TokenAdminTokensByTypeController(
                         tokenProperty[0].token?.type ?: "n/a",
                         tokenProperty.count()
                     )
-                }
+                }.toMutableList()
         }
 
         override fun delete(entity: TokenStatVirtualEntity) {
diff --git a/backend/src/main/kotlin/hu/bme/sch/cmsch/component/token/TokenAdminTokensByUsersController.kt b/backend/src/main/kotlin/hu/bme/sch/cmsch/component/token/TokenAdminTokensByUsersController.kt
index d531302e..c266a8bf 100644
--- a/backend/src/main/kotlin/hu/bme/sch/cmsch/component/token/TokenAdminTokensByUsersController.kt
+++ b/backend/src/main/kotlin/hu/bme/sch/cmsch/component/token/TokenAdminTokensByUsersController.kt
@@ -34,7 +34,7 @@ class TokenAdminTokensByUsersController(
 
     transactionManager,
     object : ManualRepository<TokenListByUserVirtualEntity, Int>() {
-        override fun findAll(): Iterable<TokenListByUserVirtualEntity> {
+        override fun findAll(): MutableList<TokenListByUserVirtualEntity> {
             return repo.findAll()
                 .groupBy { it.ownerUser?.id ?: 0 }
                 .map { it.value }
@@ -47,7 +47,7 @@ class TokenAdminTokensByUsersController(
                         groupName,
                         tokenProperty.count()
                     )
-                }
+                }.toMutableList()
         }
 
         override fun delete(entity: TokenListByUserVirtualEntity) {
diff --git a/backend/src/main/kotlin/hu/bme/sch/cmsch/component/token/TokenCollectorService.kt b/backend/src/main/kotlin/hu/bme/sch/cmsch/component/token/TokenCollectorService.kt
index be2ca29c..fce6b245 100644
--- a/backend/src/main/kotlin/hu/bme/sch/cmsch/component/token/TokenCollectorService.kt
+++ b/backend/src/main/kotlin/hu/bme/sch/cmsch/component/token/TokenCollectorService.kt
@@ -10,8 +10,7 @@ import hu.bme.sch.cmsch.repository.GroupRepository
 import hu.bme.sch.cmsch.service.TimeService
 import hu.bme.sch.cmsch.service.UserService
 import org.springframework.boot.autoconfigure.condition.ConditionalOnBean
-import org.springframework.retry.annotation.Backoff
-import org.springframework.retry.annotation.Retryable
+import org.springframework.resilience.annotation.Retryable
 import org.springframework.stereotype.Service
 import org.springframework.transaction.annotation.Isolation
 import org.springframework.transaction.annotation.Transactional
@@ -35,7 +34,7 @@ class TokenCollectorService(
     private val qrFightComponent: Optional<QrFightComponent>
 ) {
 
-    @Retryable(value = [ SQLException::class ], maxAttempts = 5, backoff = Backoff(delay = 500L, multiplier = 1.5))
+    @Retryable(value = [ SQLException::class ], maxAttempts = 5, delay = 500L, multiplier = 1.5)
     @Transactional(readOnly = false, isolation = Isolation.SERIALIZABLE)
     fun collectToken(user: CmschUser, token: String): TokenSubmittedView {
         val tokenEntity = tokenRepository.findAllByTokenAndVisibleTrue(token).firstOrNull()
@@ -59,7 +58,7 @@ class TokenCollectorService(
         return TokenSubmittedView(TokenCollectorStatus.WRONG, null, null, null)
     }
 
-    @Retryable(value = [ SQLException::class ], maxAttempts = 5, backoff = Backoff(delay = 500L, multiplier = 1.5))
+    @Retryable(value = [ SQLException::class ], maxAttempts = 5, delay = 500L, multiplier = 1.5)
     @Transactional(readOnly = false, isolation = Isolation.SERIALIZABLE)
     fun collectTokenForGroup(user: CmschUser, token: String): TokenSubmittedView {
         val groupEntity = user.groupId?.let { groupId -> groupRepository.findById(groupId).getOrNull() }
diff --git a/backend/src/main/kotlin/hu/bme/sch/cmsch/component/token/TokenComponentEntityConfiguration.kt b/backend/src/main/kotlin/hu/bme/sch/cmsch/component/token/TokenComponentEntityConfiguration.kt
index ff9c4bc9..720207d6 100644
--- a/backend/src/main/kotlin/hu/bme/sch/cmsch/component/token/TokenComponentEntityConfiguration.kt
+++ b/backend/src/main/kotlin/hu/bme/sch/cmsch/component/token/TokenComponentEntityConfiguration.kt
@@ -1,7 +1,7 @@
 package hu.bme.sch.cmsch.component.token
 
 import org.springframework.boot.autoconfigure.condition.ConditionalOnBean
-import org.springframework.boot.autoconfigure.domain.EntityScan
+import org.springframework.boot.persistence.autoconfigure.EntityScan
 import org.springframework.context.annotation.Configuration
 
 @Configuration
diff --git a/backend/src/main/kotlin/hu/bme/sch/cmsch/component/token/TokenPropertyController.kt b/backend/src/main/kotlin/hu/bme/sch/cmsch/component/token/TokenPropertyController.kt
index 149c86a6..01534dec 100644
--- a/backend/src/main/kotlin/hu/bme/sch/cmsch/component/token/TokenPropertyController.kt
+++ b/backend/src/main/kotlin/hu/bme/sch/cmsch/component/token/TokenPropertyController.kt
@@ -33,8 +33,8 @@ class TokenSubmissionsController(
 
     transactionManager,
     object : ManualRepository<TokenPropertyRawView, Int>() {
-        override fun findAll(): Iterable<TokenPropertyRawView> {
-            return repo.findAll().map { mapTokenProperty(it) }
+        override fun findAll(): MutableIterable<TokenPropertyRawView> {
+            return repo.findAll().map { mapTokenProperty(it) }.toMutableList()
         }
 
         override fun count(): Long {
diff --git a/backend/src/main/kotlin/hu/bme/sch/cmsch/component/token/TokenPropertyRepository.kt b/backend/src/main/kotlin/hu/bme/sch/cmsch/component/token/TokenPropertyRepository.kt
index 6e7dafb5..5ff15376 100644
--- a/backend/src/main/kotlin/hu/bme/sch/cmsch/component/token/TokenPropertyRepository.kt
+++ b/backend/src/main/kotlin/hu/bme/sch/cmsch/component/token/TokenPropertyRepository.kt
@@ -13,7 +13,7 @@ import java.util.*
 interface TokenPropertyRepository : CrudRepository<TokenPropertyEntity, Int>,
     EntityPageDataSource<TokenPropertyEntity, Int> {
 
-    override fun findAll(): List<TokenPropertyEntity>
+    override fun findAll(): MutableIterable<TokenPropertyEntity>
 
     fun findAllByOwnerUser_Id(owner: Int): List<TokenPropertyEntity>
 
diff --git a/backend/src/main/kotlin/hu/bme/sch/cmsch/config/AppConfig.kt b/backend/src/main/kotlin/hu/bme/sch/cmsch/config/AppConfig.kt
index 2472f078..819474c8 100644
--- a/backend/src/main/kotlin/hu/bme/sch/cmsch/config/AppConfig.kt
+++ b/backend/src/main/kotlin/hu/bme/sch/cmsch/config/AppConfig.kt
@@ -24,10 +24,9 @@ class AppConfig {
 
     @Bean
     fun objectMapper(): ObjectMapper {
-        val objectMapper = ObjectMapper()
-        objectMapper.registerKotlinModule()
-        objectMapper.setSerializationInclusion(JsonInclude.Include.NON_NULL)
-        return objectMapper
+        return ObjectMapper()
+            .registerKotlinModule()
+            .setDefaultPropertyInclusion(JsonInclude.Include.NON_NULL)
     }
 
     @Bean
@@ -43,7 +42,7 @@ class AppConfig {
                 }
                 try {
                     return URI("https://$source").toURL()
-                } catch (ex: Exception) {
+                } catch (_: Exception) {
                     // Ignore
                 }
                 return null
diff --git a/backend/src/main/kotlin/hu/bme/sch/cmsch/config/SecurityConfig.kt b/backend/src/main/kotlin/hu/bme/sch/cmsch/config/SecurityConfig.kt
index d1019a0a..0a970d08 100644
--- a/backend/src/main/kotlin/hu/bme/sch/cmsch/config/SecurityConfig.kt
+++ b/backend/src/main/kotlin/hu/bme/sch/cmsch/config/SecurityConfig.kt
@@ -17,14 +17,11 @@ import hu.bme.sch.cmsch.service.AuditLogService
 import hu.bme.sch.cmsch.service.JwtTokenProvider
 import hu.bme.sch.cmsch.service.StorageService
 import org.slf4j.LoggerFactory
-import org.springframework.beans.factory.annotation.Value
 import org.springframework.boot.autoconfigure.condition.ConditionalOnBean
 import org.springframework.context.annotation.Bean
 import org.springframework.context.annotation.Configuration
-import org.springframework.core.Ordered
 import org.springframework.http.HttpHeaders
 import org.springframework.http.MediaType
-import org.springframework.retry.annotation.EnableRetry
 import org.springframework.security.config.Customizer
 import org.springframework.security.config.annotation.web.builders.HttpSecurity
 import org.springframework.security.config.annotation.web.configuration.EnableWebSecurity
@@ -40,7 +37,6 @@ import java.util.*
 
 @EnableWebSecurity
 @Configuration
-@EnableRetry(order = Ordered.HIGHEST_PRECEDENCE)
 @ConditionalOnBean(LoginComponent::class)
 class SecurityConfig(
     private val clientRegistrationRepository: ClientRegistrationRepository,
@@ -51,7 +47,6 @@ class SecurityConfig(
     private val authschLoginService: LoginService,
     private val loginComponent: LoginComponent,
     private val startupPropertyConfig: StartupPropertyConfig,
-    @param:Value("\${custom.keycloak.base-url:http://localhost:8081/auth/realms/master}") private val keycloakBaseUrl: String,
     private val auditLogService: AuditLogService
 ) {
 
diff --git a/backend/src/main/kotlin/hu/bme/sch/cmsch/controller/ServerSideErrorController.kt b/backend/src/main/kotlin/hu/bme/sch/cmsch/controller/ServerSideErrorController.kt
index fc34a548..cb99d3e2 100644
--- a/backend/src/main/kotlin/hu/bme/sch/cmsch/controller/ServerSideErrorController.kt
+++ b/backend/src/main/kotlin/hu/bme/sch/cmsch/controller/ServerSideErrorController.kt
@@ -5,7 +5,7 @@ import hu.bme.sch.cmsch.util.getUserOrNull
 import jakarta.servlet.RequestDispatcher
 import jakarta.servlet.http.HttpServletRequest
 import jakarta.servlet.http.HttpServletResponse
-import org.springframework.boot.web.servlet.error.ErrorController
+import org.springframework.boot.webmvc.error.ErrorController
 import org.springframework.security.core.Authentication
 import org.springframework.stereotype.Controller
 import org.springframework.ui.Model
diff --git a/backend/src/main/kotlin/hu/bme/sch/cmsch/controller/admin/SettingsController.kt b/backend/src/main/kotlin/hu/bme/sch/cmsch/controller/admin/SettingsController.kt
index 516bbcb7..68906292 100644
--- a/backend/src/main/kotlin/hu/bme/sch/cmsch/controller/admin/SettingsController.kt
+++ b/backend/src/main/kotlin/hu/bme/sch/cmsch/controller/admin/SettingsController.kt
@@ -72,10 +72,12 @@ class SettingsController(
 
         auth.getUser().refresh(user)
         adminMenuService.invalidateUser(user.internalId)
-        SecurityContextHolder.getContext().authentication = UsernamePasswordAuthenticationToken(
-            auth.principal, auth.credentials,
-            mutableListOf(SimpleGrantedAuthority("ROLE_${user.role.name}"))
-        )
+        SecurityContextHolder.getContext().authentication = auth.principal?.let {
+            UsernamePasswordAuthenticationToken(
+                it, auth.credentials,
+                mutableListOf(SimpleGrantedAuthority("ROLE_${user.role.name}"))
+            )
+        }
         log.info("User ${user.fullName} has just relogged")
 
         return "redirect:/admin/control/settings"
diff --git a/backend/src/main/kotlin/hu/bme/sch/cmsch/controller/admin/TszImportDashboard.kt b/backend/src/main/kotlin/hu/bme/sch/cmsch/controller/admin/TszImportDashboard.kt
index 70824626..7394aed1 100644
--- a/backend/src/main/kotlin/hu/bme/sch/cmsch/controller/admin/TszImportDashboard.kt
+++ b/backend/src/main/kotlin/hu/bme/sch/cmsch/controller/admin/TszImportDashboard.kt
@@ -256,7 +256,7 @@ class TszImportDashboard(
                     group.staff3 = if (mappings.value.size > 2) mappings.value[2] else ""
                     group.staff4 = if (mappings.value.size > 3) mappings.value[3] else ""
                     return@map group
-                }
+                }.toMutableList()
                 groupRepository.saveAll(affectedGroups)
                 affectedSize = affectedGroups.size
             }
@@ -289,4 +289,4 @@ class TszImportDashboard(
         return results
     }
 
-}
\ No newline at end of file
+}
diff --git a/backend/src/main/kotlin/hu/bme/sch/cmsch/controller/dashboard/InstanceInfoDashboard.kt b/backend/src/main/kotlin/hu/bme/sch/cmsch/controller/dashboard/InstanceInfoDashboard.kt
index 865c30a8..e5d754be 100644
--- a/backend/src/main/kotlin/hu/bme/sch/cmsch/controller/dashboard/InstanceInfoDashboard.kt
+++ b/backend/src/main/kotlin/hu/bme/sch/cmsch/controller/dashboard/InstanceInfoDashboard.kt
@@ -14,9 +14,9 @@ import hu.bme.sch.cmsch.service.ControlPermissions
 import hu.bme.sch.cmsch.service.TimeService
 import hu.bme.sch.cmsch.statistics.UserActivityFilter
 import org.apache.catalina.util.ServerInfo
-import org.springframework.boot.autoconfigure.web.ServerProperties
-import org.springframework.boot.autoconfigure.web.servlet.MultipartProperties
 import org.springframework.boot.info.BuildProperties
+import org.springframework.boot.servlet.autoconfigure.MultipartProperties
+import org.springframework.boot.web.server.autoconfigure.ServerProperties
 import org.springframework.core.env.Environment
 import org.springframework.stereotype.Controller
 import org.springframework.web.bind.annotation.RequestMapping
@@ -100,11 +100,7 @@ class InstanceInfoDashboard(
             listOf("Token ownership mode",          startupPropertyConfig.tokenOwnershipMode.name),
             listOf("Challenge ownership mode",      startupPropertyConfig.challengeOwnershipMode.name),
             listOf("Race ownership mode",           startupPropertyConfig.raceOwnershipMode.name),
-            listOf("Max threads",                   serverProperties?.tomcat?.threads?.max?.toString() ?: "n/a"),
-            listOf("Min spare threads",             serverProperties?.tomcat?.threads?.minSpare?.toString() ?: "n/a"),
-            listOf("Accept count",                  serverProperties?.tomcat?.acceptCount?.toString() ?: "n/a"),
-            listOf("Max connections",               serverProperties?.tomcat?.maxConnections?.toString() ?: "n/a"),
-            listOf("Max swallow size ( ͡° ͜ʖ ͡°)",  serverProperties?.tomcat?.maxSwallowSize?.toString() ?: "n/a"),
+            listOf("Max request header size",       serverProperties?.maxHttpRequestHeaderSize?.toString() ?: "n/a"),
             listOf("Max file size",                 multipartProperties?.maxFileSize?.toString() ?: "n/a"),
             listOf("Max request size",              multipartProperties?.maxRequestSize?.toString() ?: "n/a"),
             listOf("Datasource url",                env.getProperty("spring.datasource.url", "n/a")),
diff --git a/backend/src/main/kotlin/hu/bme/sch/cmsch/repository/EntityPageDataSource.kt b/backend/src/main/kotlin/hu/bme/sch/cmsch/repository/EntityPageDataSource.kt
index 0e28b2ea..c3d0d801 100644
--- a/backend/src/main/kotlin/hu/bme/sch/cmsch/repository/EntityPageDataSource.kt
+++ b/backend/src/main/kotlin/hu/bme/sch/cmsch/repository/EntityPageDataSource.kt
@@ -4,7 +4,7 @@ import java.util.*
 
 interface EntityPageDataSource<T, ID> {
 
-    fun findAll(): Iterable<T>
+    fun findAll(): MutableIterable<T>
 
     fun findById(id: ID): Optional<T>
 
@@ -14,8 +14,8 @@ interface EntityPageDataSource<T, ID> {
 
     fun <S : T & Any> save(entity: S): S
 
-    fun <S : T?> saveAll(entities: Iterable<S>): Iterable<S>
+    fun <S : T> saveAll(entities: MutableIterable<S>): MutableIterable<S>
 
     fun deleteAll()
 
-}
\ No newline at end of file
+}
diff --git a/backend/src/main/kotlin/hu/bme/sch/cmsch/repository/ManualRepository.kt b/backend/src/main/kotlin/hu/bme/sch/cmsch/repository/ManualRepository.kt
index 4daa8fd5..a539a233 100644
--- a/backend/src/main/kotlin/hu/bme/sch/cmsch/repository/ManualRepository.kt
+++ b/backend/src/main/kotlin/hu/bme/sch/cmsch/repository/ManualRepository.kt
@@ -4,7 +4,7 @@ import java.util.*
 
 abstract class ManualRepository<T, ID> : EntityPageDataSource<T, ID> {
 
-    override fun findAll(): Iterable<T> =
+    override fun findAll(): MutableIterable<T> =
         throw UnsupportedOperationException("This data source does not support: findAll()")
 
     override fun count(): Long =
@@ -13,7 +13,7 @@ abstract class ManualRepository<T, ID> : EntityPageDataSource<T, ID> {
     override fun deleteAll(): Unit =
         throw UnsupportedOperationException("This data source does not support: deleteAll()")
 
-    override fun <S : T?> saveAll(entities: Iterable<S>): Iterable<S> =
+    override fun <S : T> saveAll(entities: MutableIterable<S>): MutableIterable<S> =
         throw UnsupportedOperationException("This data source does not support: saveAll(entities)")
 
     override fun <S : T & Any> save(entity: S): S =
diff --git a/backend/src/main/kotlin/hu/bme/sch/cmsch/repository/UserRepository.kt b/backend/src/main/kotlin/hu/bme/sch/cmsch/repository/UserRepository.kt
index 9ba8dd13..f836d4f5 100644
--- a/backend/src/main/kotlin/hu/bme/sch/cmsch/repository/UserRepository.kt
+++ b/backend/src/main/kotlin/hu/bme/sch/cmsch/repository/UserRepository.kt
@@ -41,8 +41,8 @@ interface UserRepository : CrudRepository<UserEntity, Int>,
     fun findAllByGroupName(groupName: String): List<UserEntity>
     fun findByEmail(email: String): Optional<UserEntity>
     fun countAllByGroup(group: GroupEntity): Long
-    fun findAllByRoleOrRoleOrPermissionsNot(role1: RoleType, role2: RoleType, emptyString: String): List<UserEntity>
-    fun findAllByRoleOrRole(role1: RoleType, role2: RoleType): List<UserEntity>
+    fun findAllByRoleOrRoleOrPermissionsNot(role1: RoleType, role2: RoleType, emptyString: String): MutableList<UserEntity>
+    fun findAllByRoleOrRole(role1: RoleType, role2: RoleType): MutableList<UserEntity>
 
     @Query("SELECT NEW hu.bme.sch.cmsch.repository.UserSelectorView(e.id, e.fullName, e.alias, e.provider, e.email) FROM UserEntity e")
     fun findAllSelectorView(): List<UserSelectorView>
diff --git a/backend/src/main/kotlin/hu/bme/sch/cmsch/service/UserService.kt b/backend/src/main/kotlin/hu/bme/sch/cmsch/service/UserService.kt
index 2692bc88..f83e5099 100644
--- a/backend/src/main/kotlin/hu/bme/sch/cmsch/service/UserService.kt
+++ b/backend/src/main/kotlin/hu/bme/sch/cmsch/service/UserService.kt
@@ -10,8 +10,7 @@ import hu.bme.sch.cmsch.repository.GroupToUserMappingRepository
 import hu.bme.sch.cmsch.repository.GuildToUserMappingRepository
 import hu.bme.sch.cmsch.repository.UserRepository
 import hu.bme.sch.cmsch.repository.UserSelectorView
-import org.springframework.retry.annotation.Backoff
-import org.springframework.retry.annotation.Retryable
+import org.springframework.resilience.annotation.Retryable
 import org.springframework.stereotype.Service
 import org.springframework.transaction.annotation.Isolation
 import org.springframework.transaction.annotation.Transactional
@@ -29,7 +28,7 @@ open class UserService(
 
     private val userConfigReader = objectMapper.readerFor(UserConfig::class.java)
 
-    @Retryable(value = [ SQLException::class ], maxAttempts = 5, backoff = Backoff(delay = 500L, multiplier = 1.5))
+    @Retryable(value = [ SQLException::class ], maxAttempts = 5, delay = 500L, multiplier = 1.5)
     @Transactional(readOnly = false, isolation = Isolation.SERIALIZABLE)
     open fun save(user: UserEntity) {
         users.save(user)
diff --git a/backend/src/main/kotlin/hu/bme/sch/cmsch/statistics/StatisticsFilterConfig.kt b/backend/src/main/kotlin/hu/bme/sch/cmsch/statistics/StatisticsFilterConfig.kt
index 06a4f293..9a33cada 100644
--- a/backend/src/main/kotlin/hu/bme/sch/cmsch/statistics/StatisticsFilterConfig.kt
+++ b/backend/src/main/kotlin/hu/bme/sch/cmsch/statistics/StatisticsFilterConfig.kt
@@ -19,9 +19,8 @@ class StatisticsFilterConfig(
 
     @Bean
     fun userActivityFilterRegistration(): FilterRegistrationBean<UserActivityFilter> {
-        val registration = FilterRegistrationBean<UserActivityFilter>()
-        registration.filter = userActivityFilter.orElseThrow()
+        val registration = FilterRegistrationBean<UserActivityFilter>(userActivityFilter.orElseThrow())
         registration.addUrlPatterns("/api/*")
         return registration
     }
-}
\ No newline at end of file
+}
diff --git a/backend/src/main/resources/config/application.properties b/backend/src/main/resources/config/application.properties
index 136f4d69..2d2337d6 100644
--- a/backend/src/main/resources/config/application.properties
+++ b/backend/src/main/resources/config/application.properties
@@ -172,5 +172,3 @@ management.endpoint.health.probes.enabled=true
 management.endpoints.web.exposure.include=*
 spring.jpa.properties.hibernate.generate_statistics=true
 management.metrics.tags.application=insert_application_name
-# It's spamming the console otherwise
-logging.level.org.hibernate=warn