diff --git a/gradle/libs.versions.toml b/gradle/libs.versions.toml
index 5054fc9e0..bf0fd3762 100644
--- a/gradle/libs.versions.toml
+++ b/gradle/libs.versions.toml
@@ -12,7 +12,7 @@ dex2jar = "2.4.36"
 polyglot = "25.0.3"
 settings = "1.3.0"
 twelvemonkeys = "3.13.1"
-graphqlkotlin = "9.2.0"
+graphqlkotlin = "10.0.0-alpha.3"
 xmlserialization = "0.91.3"
 ktlint = "1.8.0"
 koin = "4.2.1"
diff --git a/server/build.gradle.kts b/server/build.gradle.kts
index 4e11d4a81..af90c3b04 100644
--- a/server/build.gradle.kts
+++ b/server/build.gradle.kts
@@ -43,7 +43,7 @@ dependencies {
 
     // Javalin api
     implementation(libs.bundles.javalin)
-    implementation(libs.bundles.jackson)
+    //implementation(libs.bundles.jackson)
 
     // GraphQL
     implementation(libs.graphql.kotlin.server)
diff --git a/server/src/main/kotlin/suwayomi/tachidesk/graphql/AsDataFetcherResult.kt b/server/src/main/kotlin/suwayomi/tachidesk/graphql/AsDataFetcherResult.kt
index 6c3a0f74a..cb23ed779 100644
--- a/server/src/main/kotlin/suwayomi/tachidesk/graphql/AsDataFetcherResult.kt
+++ b/server/src/main/kotlin/suwayomi/tachidesk/graphql/AsDataFetcherResult.kt
@@ -6,7 +6,7 @@ import io.github.oshai.kotlinlogging.KotlinLogging
 
 val logger = KotlinLogging.logger { }
 
-inline fun <T> asDataFetcherResult(block: () -> T): DataFetcherResult<T?> {
+inline fun <T : Any> asDataFetcherResult(block: () -> T): DataFetcherResult<T> {
     val result =
         runCatching {
             block()
@@ -15,13 +15,13 @@ inline fun <T> asDataFetcherResult(block: () -> T): DataFetcherResult<T?> {
     if (result.isFailure) {
         logger.error(result.exceptionOrNull()) { "asDataFetcherResult: failed due to" }
         return DataFetcherResult
-            .newResult<T?>()
-            .error(result.exceptionOrNull()?.toGraphQLError())
+            .newResult<T>()
+            .error(result.exceptionOrNull()!!.toGraphQLError())
             .build()
     }
 
     return DataFetcherResult
-        .newResult<T?>()
+        .newResult<T>()
         .data(result.getOrNull())
         .build()
 }
diff --git a/server/src/main/kotlin/suwayomi/tachidesk/graphql/cache/CustomCacheMap.kt b/server/src/main/kotlin/suwayomi/tachidesk/graphql/cache/CustomCacheMap.kt
index 742da59a8..7f9b946b2 100644
--- a/server/src/main/kotlin/suwayomi/tachidesk/graphql/cache/CustomCacheMap.kt
+++ b/server/src/main/kotlin/suwayomi/tachidesk/graphql/cache/CustomCacheMap.kt
@@ -3,12 +3,8 @@ package suwayomi.tachidesk.graphql.cache
 import org.dataloader.CacheMap
 import java.util.concurrent.CompletableFuture
 
-class CustomCacheMap<K, V> : CacheMap<K, V> {
-    private val cache: MutableMap<K, CompletableFuture<V>>
-
-    init {
-        cache = HashMap()
-    }
+class CustomCacheMap<K : Any, V : Any> : CacheMap<K, V> {
+    private val cache: MutableMap<K, CompletableFuture<V>> = HashMap()
 
     override fun containsKey(key: K): Boolean = cache.containsKey(key)
 
@@ -18,12 +14,12 @@ class CustomCacheMap<K, V> : CacheMap<K, V> {
 
     override fun getAll(): Collection<CompletableFuture<V>> = cache.values
 
-    override fun set(
+    override fun putIfAbsentAtomically(
         key: K,
         value: CompletableFuture<V>,
-    ): CacheMap<K, V> {
+    ): CompletableFuture<V> {
         cache[key] = value
-        return this
+        return value
     }
 
     override fun delete(key: K): CacheMap<K, V> {
@@ -35,4 +31,8 @@ class CustomCacheMap<K, V> : CacheMap<K, V> {
         cache.clear()
         return this
     }
+
+    override fun size(): Int {
+        return cache.size
+    }
 }
diff --git a/server/src/main/kotlin/suwayomi/tachidesk/graphql/dataLoaders/ChapterDataLoader.kt b/server/src/main/kotlin/suwayomi/tachidesk/graphql/dataLoaders/ChapterDataLoader.kt
index f0fe0a898..44ef6de3c 100644
--- a/server/src/main/kotlin/suwayomi/tachidesk/graphql/dataLoaders/ChapterDataLoader.kt
+++ b/server/src/main/kotlin/suwayomi/tachidesk/graphql/dataLoaders/ChapterDataLoader.kt
@@ -24,11 +24,11 @@ import suwayomi.tachidesk.graphql.types.ChapterType
 import suwayomi.tachidesk.manga.model.table.ChapterTable
 import suwayomi.tachidesk.server.JavalinSetup.future
 
-class ChapterDataLoader : KotlinDataLoader<Int, ChapterType?> {
+class ChapterDataLoader : KotlinDataLoader<Int, ChapterType> {
     override val dataLoaderName = "ChapterDataLoader"
 
-    override fun getDataLoader(graphQLContext: GraphQLContext): DataLoader<Int, ChapterType?> =
-        DataLoaderFactory.newDataLoader<Int, ChapterType> { ids ->
+    override fun getDataLoader(graphQLContext: GraphQLContext): DataLoader<Int, ChapterType> =
+        DataLoaderFactory.newDataLoader { ids ->
             future {
                 transaction {
                     addLogger(Slf4jSqlDebugLogger)
@@ -48,7 +48,7 @@ class ChaptersForMangaDataLoader : KotlinDataLoader<Int, ChapterNodeList> {
     override val dataLoaderName = "ChaptersForMangaDataLoader"
 
     override fun getDataLoader(graphQLContext: GraphQLContext): DataLoader<Int, ChapterNodeList> =
-        DataLoaderFactory.newDataLoader<Int, ChapterNodeList> { ids ->
+        DataLoaderFactory.newDataLoader { ids ->
             future {
                 transaction {
                     addLogger(Slf4jSqlDebugLogger)
@@ -68,7 +68,7 @@ class DownloadedChapterCountForMangaDataLoader : KotlinDataLoader<Int, Int> {
     override val dataLoaderName = "DownloadedChapterCountForMangaDataLoader"
 
     override fun getDataLoader(graphQLContext: GraphQLContext): DataLoader<Int, Int> =
-        DataLoaderFactory.newDataLoader<Int, Int> { ids ->
+        DataLoaderFactory.newDataLoader { ids ->
             future {
                 transaction {
                     addLogger(Slf4jSqlDebugLogger)
@@ -90,7 +90,7 @@ class UnreadChapterCountForMangaDataLoader : KotlinDataLoader<Int, Int> {
     override val dataLoaderName = "UnreadChapterCountForMangaDataLoader"
 
     override fun getDataLoader(graphQLContext: GraphQLContext): DataLoader<Int, Int> =
-        DataLoaderFactory.newDataLoader<Int, Int> { ids ->
+        DataLoaderFactory.newDataLoader { ids ->
             future {
                 transaction {
                     addLogger(Slf4jSqlDebugLogger)
@@ -112,7 +112,7 @@ class BookmarkedChapterCountForMangaDataLoader : KotlinDataLoader<Int, Int> {
     override val dataLoaderName = "BookmarkedChapterCountForMangaDataLoader"
 
     override fun getDataLoader(graphQLContext: GraphQLContext): DataLoader<Int, Int> =
-        DataLoaderFactory.newDataLoader<Int, Int> { ids ->
+        DataLoaderFactory.newDataLoader { ids ->
             future {
                 transaction {
                     addLogger(Slf4jSqlDebugLogger)
@@ -157,11 +157,11 @@ class HasDuplicateChaptersForMangaDataLoader : KotlinDataLoader<Int, Boolean> {
         }
 }
 
-class LastReadChapterForMangaDataLoader : KotlinDataLoader<Int, ChapterType?> {
+class LastReadChapterForMangaDataLoader : KotlinDataLoader<Int, ChapterType> {
     override val dataLoaderName = "LastReadChapterForMangaDataLoader"
 
-    override fun getDataLoader(graphQLContext: GraphQLContext): DataLoader<Int, ChapterType?> =
-        DataLoaderFactory.newDataLoader<Int, ChapterType?> { ids ->
+    override fun getDataLoader(graphQLContext: GraphQLContext): DataLoader<Int, ChapterType> =
+        DataLoaderFactory.newDataLoader { ids ->
             future {
                 transaction {
                     addLogger(Slf4jSqlDebugLogger)
@@ -177,11 +177,11 @@ class LastReadChapterForMangaDataLoader : KotlinDataLoader<Int, ChapterType?> {
         }
 }
 
-class LatestReadChapterForMangaDataLoader : KotlinDataLoader<Int, ChapterType?> {
+class LatestReadChapterForMangaDataLoader : KotlinDataLoader<Int, ChapterType> {
     override val dataLoaderName = "LatestReadChapterForMangaDataLoader"
 
-    override fun getDataLoader(graphQLContext: GraphQLContext): DataLoader<Int, ChapterType?> =
-        DataLoaderFactory.newDataLoader<Int, ChapterType?> { ids ->
+    override fun getDataLoader(graphQLContext: GraphQLContext): DataLoader<Int, ChapterType> =
+        DataLoaderFactory.newDataLoader { ids ->
             future {
                 transaction {
                     addLogger(Slf4jSqlDebugLogger)
@@ -197,11 +197,11 @@ class LatestReadChapterForMangaDataLoader : KotlinDataLoader<Int, ChapterType?>
         }
 }
 
-class LatestFetchedChapterForMangaDataLoader : KotlinDataLoader<Int, ChapterType?> {
+class LatestFetchedChapterForMangaDataLoader : KotlinDataLoader<Int, ChapterType> {
     override val dataLoaderName = "LatestFetchedChapterForMangaDataLoader"
 
-    override fun getDataLoader(graphQLContext: GraphQLContext): DataLoader<Int, ChapterType?> =
-        DataLoaderFactory.newDataLoader<Int, ChapterType?> { ids ->
+    override fun getDataLoader(graphQLContext: GraphQLContext): DataLoader<Int, ChapterType> =
+        DataLoaderFactory.newDataLoader { ids ->
             future {
                 transaction {
                     addLogger(Slf4jSqlDebugLogger)
@@ -217,11 +217,11 @@ class LatestFetchedChapterForMangaDataLoader : KotlinDataLoader<Int, ChapterType
         }
 }
 
-class LatestUploadedChapterForMangaDataLoader : KotlinDataLoader<Int, ChapterType?> {
+class LatestUploadedChapterForMangaDataLoader : KotlinDataLoader<Int, ChapterType> {
     override val dataLoaderName = "LatestUploadedChapterForMangaDataLoader"
 
-    override fun getDataLoader(graphQLContext: GraphQLContext): DataLoader<Int, ChapterType?> =
-        DataLoaderFactory.newDataLoader<Int, ChapterType?> { ids ->
+    override fun getDataLoader(graphQLContext: GraphQLContext): DataLoader<Int, ChapterType> =
+        DataLoaderFactory.newDataLoader { ids ->
             future {
                 transaction {
                     addLogger(Slf4jSqlDebugLogger)
@@ -237,11 +237,11 @@ class LatestUploadedChapterForMangaDataLoader : KotlinDataLoader<Int, ChapterTyp
         }
 }
 
-class FirstUnreadChapterForMangaDataLoader : KotlinDataLoader<Int, ChapterType?> {
+class FirstUnreadChapterForMangaDataLoader : KotlinDataLoader<Int, ChapterType> {
     override val dataLoaderName = "FirstUnreadChapterForMangaDataLoader"
 
-    override fun getDataLoader(graphQLContext: GraphQLContext): DataLoader<Int, ChapterType?> =
-        DataLoaderFactory.newDataLoader<Int, ChapterType?> { ids ->
+    override fun getDataLoader(graphQLContext: GraphQLContext): DataLoader<Int, ChapterType> =
+        DataLoaderFactory.newDataLoader { ids ->
             future {
                 transaction {
                     addLogger(Slf4jSqlDebugLogger)
@@ -257,11 +257,11 @@ class FirstUnreadChapterForMangaDataLoader : KotlinDataLoader<Int, ChapterType?>
         }
 }
 
-class HighestNumberedChapterForMangaDataLoader : KotlinDataLoader<Int, ChapterType?> {
+class HighestNumberedChapterForMangaDataLoader : KotlinDataLoader<Int, ChapterType> {
     override val dataLoaderName = "HighestNumberedChapterForMangaDataLoader"
 
-    override fun getDataLoader(graphQLContext: GraphQLContext): DataLoader<Int, ChapterType?> =
-        DataLoaderFactory.newDataLoader<Int, ChapterType?> { ids ->
+    override fun getDataLoader(graphQLContext: GraphQLContext): DataLoader<Int, ChapterType> =
+        DataLoaderFactory.newDataLoader { ids ->
             future {
                 transaction {
                     addLogger(Slf4jSqlDebugLogger)
diff --git a/server/src/main/kotlin/suwayomi/tachidesk/graphql/dataLoaders/ExtensionDataLoader.kt b/server/src/main/kotlin/suwayomi/tachidesk/graphql/dataLoaders/ExtensionDataLoader.kt
index 2c7be2fa6..c3b4b6955 100644
--- a/server/src/main/kotlin/suwayomi/tachidesk/graphql/dataLoaders/ExtensionDataLoader.kt
+++ b/server/src/main/kotlin/suwayomi/tachidesk/graphql/dataLoaders/ExtensionDataLoader.kt
@@ -20,10 +20,10 @@ import suwayomi.tachidesk.manga.model.table.ExtensionTable
 import suwayomi.tachidesk.manga.model.table.SourceTable
 import suwayomi.tachidesk.server.JavalinSetup.future
 
-class ExtensionDataLoader : KotlinDataLoader<String, ExtensionType?> {
+class ExtensionDataLoader : KotlinDataLoader<String, ExtensionType> {
     override val dataLoaderName = "ExtensionDataLoader"
 
-    override fun getDataLoader(graphQLContext: GraphQLContext): DataLoader<String, ExtensionType?> =
+    override fun getDataLoader(graphQLContext: GraphQLContext): DataLoader<String, ExtensionType> =
         DataLoaderFactory.newDataLoader { ids ->
             future {
                 transaction {
@@ -40,10 +40,10 @@ class ExtensionDataLoader : KotlinDataLoader<String, ExtensionType?> {
         }
 }
 
-class ExtensionForSourceDataLoader : KotlinDataLoader<Long, ExtensionType?> {
+class ExtensionForSourceDataLoader : KotlinDataLoader<Long, ExtensionType> {
     override val dataLoaderName = "ExtensionForSourceDataLoader"
 
-    override fun getDataLoader(graphQLContext: GraphQLContext): DataLoader<Long, ExtensionType?> =
+    override fun getDataLoader(graphQLContext: GraphQLContext): DataLoader<Long, ExtensionType> =
         DataLoaderFactory.newDataLoader { ids ->
             future {
                 transaction {
diff --git a/server/src/main/kotlin/suwayomi/tachidesk/graphql/dataLoaders/MangaDataLoader.kt b/server/src/main/kotlin/suwayomi/tachidesk/graphql/dataLoaders/MangaDataLoader.kt
index 0775d71ad..a49b3260d 100644
--- a/server/src/main/kotlin/suwayomi/tachidesk/graphql/dataLoaders/MangaDataLoader.kt
+++ b/server/src/main/kotlin/suwayomi/tachidesk/graphql/dataLoaders/MangaDataLoader.kt
@@ -25,10 +25,10 @@ import suwayomi.tachidesk.manga.model.table.CategoryMangaTable
 import suwayomi.tachidesk.manga.model.table.MangaTable
 import suwayomi.tachidesk.server.JavalinSetup.future
 
-class MangaDataLoader : KotlinDataLoader<Int, MangaType?> {
+class MangaDataLoader : KotlinDataLoader<Int, MangaType> {
     override val dataLoaderName = "MangaDataLoader"
 
-    override fun getDataLoader(graphQLContext: GraphQLContext): DataLoader<Int, MangaType?> =
+    override fun getDataLoader(graphQLContext: GraphQLContext): DataLoader<Int, MangaType> =
         DataLoaderFactory.newDataLoader { ids ->
             future {
                 transaction {
@@ -122,6 +122,6 @@ class MangaForIdsDataLoader : KotlinDataLoader<List<Int>, MangaNodeList> {
                     }
                 }
             },
-            DataLoaderOptions.newOptions().setCacheMap(CustomCacheMap<List<Int>, MangaNodeList>()),
+            DataLoaderOptions.newOptions().setCacheMap(CustomCacheMap<List<Int>, MangaNodeList>()).build(),
         )
 }
diff --git a/server/src/main/kotlin/suwayomi/tachidesk/graphql/dataLoaders/MetaDataLoader.kt b/server/src/main/kotlin/suwayomi/tachidesk/graphql/dataLoaders/MetaDataLoader.kt
index a01f2392c..d2515bca1 100644
--- a/server/src/main/kotlin/suwayomi/tachidesk/graphql/dataLoaders/MetaDataLoader.kt
+++ b/server/src/main/kotlin/suwayomi/tachidesk/graphql/dataLoaders/MetaDataLoader.kt
@@ -20,11 +20,11 @@ import suwayomi.tachidesk.manga.model.table.MangaMetaTable
 import suwayomi.tachidesk.manga.model.table.SourceMetaTable
 import suwayomi.tachidesk.server.JavalinSetup.future
 
-class GlobalMetaDataLoader : KotlinDataLoader<String, GlobalMetaType?> {
+class GlobalMetaDataLoader : KotlinDataLoader<String, GlobalMetaType> {
     override val dataLoaderName = "GlobalMetaDataLoader"
 
-    override fun getDataLoader(graphQLContext: GraphQLContext): DataLoader<String, GlobalMetaType?> =
-        DataLoaderFactory.newDataLoader<String, GlobalMetaType?> { ids ->
+    override fun getDataLoader(graphQLContext: GraphQLContext): DataLoader<String, GlobalMetaType> =
+        DataLoaderFactory.newDataLoader<String, GlobalMetaType> { ids ->
             future {
                 transaction {
                     addLogger(Slf4jSqlDebugLogger)
diff --git a/server/src/main/kotlin/suwayomi/tachidesk/graphql/dataLoaders/SourceDataLoader.kt b/server/src/main/kotlin/suwayomi/tachidesk/graphql/dataLoaders/SourceDataLoader.kt
index be3c60e0b..3fc2269cf 100644
--- a/server/src/main/kotlin/suwayomi/tachidesk/graphql/dataLoaders/SourceDataLoader.kt
+++ b/server/src/main/kotlin/suwayomi/tachidesk/graphql/dataLoaders/SourceDataLoader.kt
@@ -22,10 +22,10 @@ import suwayomi.tachidesk.manga.model.table.ExtensionTable
 import suwayomi.tachidesk.manga.model.table.SourceTable
 import suwayomi.tachidesk.server.JavalinSetup.future
 
-class SourceDataLoader : KotlinDataLoader<Long, SourceType?> {
+class SourceDataLoader : KotlinDataLoader<Long, SourceType> {
     override val dataLoaderName = "SourceDataLoader"
 
-    override fun getDataLoader(graphQLContext: GraphQLContext): DataLoader<Long, SourceType?> =
+    override fun getDataLoader(graphQLContext: GraphQLContext): DataLoader<Long, SourceType> =
         DataLoaderFactory.newDataLoader { ids ->
             future {
                 transaction {
diff --git a/server/src/main/kotlin/suwayomi/tachidesk/graphql/mutations/CategoryMutation.kt b/server/src/main/kotlin/suwayomi/tachidesk/graphql/mutations/CategoryMutation.kt
index 132a399e5..a899fa9ae 100644
--- a/server/src/main/kotlin/suwayomi/tachidesk/graphql/mutations/CategoryMutation.kt
+++ b/server/src/main/kotlin/suwayomi/tachidesk/graphql/mutations/CategoryMutation.kt
@@ -42,7 +42,7 @@ class CategoryMutation {
     )
 
     @RequireAuth
-    fun setCategoryMeta(input: SetCategoryMetaInput): DataFetcherResult<SetCategoryMetaPayload?> =
+    fun setCategoryMeta(input: SetCategoryMetaInput): DataFetcherResult<SetCategoryMetaPayload> =
         asDataFetcherResult {
             val (clientMutationId, meta) = input
 
@@ -64,7 +64,7 @@ class CategoryMutation {
     )
 
     @RequireAuth
-    fun deleteCategoryMeta(input: DeleteCategoryMetaInput): DataFetcherResult<DeleteCategoryMetaPayload?> =
+    fun deleteCategoryMeta(input: DeleteCategoryMetaInput): DataFetcherResult<DeleteCategoryMetaPayload> =
         asDataFetcherResult {
             val (clientMutationId, categoryId, key) = input
 
@@ -110,7 +110,7 @@ class CategoryMutation {
     )
 
     @RequireAuth
-    fun setCategoryMetas(input: SetCategoryMetasInput): DataFetcherResult<SetCategoryMetasPayload?> =
+    fun setCategoryMetas(input: SetCategoryMetasInput): DataFetcherResult<SetCategoryMetasPayload> =
         asDataFetcherResult {
             val (clientMutationId, items) = input
 
@@ -166,7 +166,7 @@ class CategoryMutation {
     )
 
     @RequireAuth
-    fun deleteCategoryMetas(input: DeleteCategoryMetasInput): DataFetcherResult<DeleteCategoryMetasPayload?> =
+    fun deleteCategoryMetas(input: DeleteCategoryMetasInput): DataFetcherResult<DeleteCategoryMetasPayload> =
         asDataFetcherResult {
             val (clientMutationId, items) = input
 
@@ -291,7 +291,7 @@ class CategoryMutation {
     }
 
     @RequireAuth
-    fun updateCategory(input: UpdateCategoryInput): DataFetcherResult<UpdateCategoryPayload?> =
+    fun updateCategory(input: UpdateCategoryInput): DataFetcherResult<UpdateCategoryPayload> =
         asDataFetcherResult {
             val (clientMutationId, id, patch) = input
 
@@ -309,7 +309,7 @@ class CategoryMutation {
         }
 
     @RequireAuth
-    fun updateCategories(input: UpdateCategoriesInput): DataFetcherResult<UpdateCategoriesPayload?> =
+    fun updateCategories(input: UpdateCategoriesInput): DataFetcherResult<UpdateCategoriesPayload> =
         asDataFetcherResult {
             val (clientMutationId, ids, patch) = input
 
@@ -338,7 +338,7 @@ class CategoryMutation {
     )
 
     @RequireAuth
-    fun updateCategoryOrder(input: UpdateCategoryOrderInput): DataFetcherResult<UpdateCategoryOrderPayload?> =
+    fun updateCategoryOrder(input: UpdateCategoryOrderInput): DataFetcherResult<UpdateCategoryOrderPayload> =
         asDataFetcherResult {
             val (clientMutationId, categoryId, position) = input
             require(position > 0) {
@@ -397,7 +397,7 @@ class CategoryMutation {
     )
 
     @RequireAuth
-    fun createCategory(input: CreateCategoryInput): DataFetcherResult<CreateCategoryPayload?> =
+    fun createCategory(input: CreateCategoryInput): DataFetcherResult<CreateCategoryPayload> =
         asDataFetcherResult {
             val (clientMutationId, name, order, default, includeInUpdate, includeInDownload) = input
             transaction {
@@ -457,7 +457,7 @@ class CategoryMutation {
     )
 
     @RequireAuth
-    fun deleteCategory(input: DeleteCategoryInput): DataFetcherResult<DeleteCategoryPayload?> {
+    fun deleteCategory(input: DeleteCategoryInput): DataFetcherResult<DeleteCategoryPayload> {
         return asDataFetcherResult {
             val (clientMutationId, categoryId) = input
             if (categoryId == 0) { // Don't delete default category
@@ -547,7 +547,7 @@ class CategoryMutation {
     }
 
     @RequireAuth
-    fun updateMangaCategories(input: UpdateMangaCategoriesInput): DataFetcherResult<UpdateMangaCategoriesPayload?> =
+    fun updateMangaCategories(input: UpdateMangaCategoriesInput): DataFetcherResult<UpdateMangaCategoriesPayload> =
         asDataFetcherResult {
             val (clientMutationId, id, patch) = input
 
@@ -565,7 +565,7 @@ class CategoryMutation {
         }
 
     @RequireAuth
-    fun updateMangasCategories(input: UpdateMangasCategoriesInput): DataFetcherResult<UpdateMangasCategoriesPayload?> =
+    fun updateMangasCategories(input: UpdateMangasCategoriesInput): DataFetcherResult<UpdateMangasCategoriesPayload> =
         asDataFetcherResult {
             val (clientMutationId, ids, patch) = input
 
diff --git a/server/src/main/kotlin/suwayomi/tachidesk/graphql/mutations/ChapterMutation.kt b/server/src/main/kotlin/suwayomi/tachidesk/graphql/mutations/ChapterMutation.kt
index 9d33fcf32..c79240379 100644
--- a/server/src/main/kotlin/suwayomi/tachidesk/graphql/mutations/ChapterMutation.kt
+++ b/server/src/main/kotlin/suwayomi/tachidesk/graphql/mutations/ChapterMutation.kt
@@ -120,7 +120,7 @@ class ChapterMutation {
     }
 
     @RequireAuth
-    fun updateChapter(input: UpdateChapterInput): DataFetcherResult<UpdateChapterPayload?> =
+    fun updateChapter(input: UpdateChapterInput): DataFetcherResult<UpdateChapterPayload> =
         asDataFetcherResult {
             val (clientMutationId, id, patch) = input
 
@@ -138,7 +138,7 @@ class ChapterMutation {
         }
 
     @RequireAuth
-    fun updateChapters(input: UpdateChaptersInput): DataFetcherResult<UpdateChaptersPayload?> =
+    fun updateChapters(input: UpdateChaptersInput): DataFetcherResult<UpdateChaptersPayload> =
         asDataFetcherResult {
             val (clientMutationId, ids, patch) = input
 
@@ -166,7 +166,7 @@ class ChapterMutation {
     )
 
     @RequireAuth
-    fun fetchChapters(input: FetchChaptersInput): CompletableFuture<DataFetcherResult<FetchChaptersPayload?>> {
+    fun fetchChapters(input: FetchChaptersInput): CompletableFuture<DataFetcherResult<FetchChaptersPayload>> {
         val (clientMutationId, mangaId) = input
 
         return future {
@@ -201,7 +201,7 @@ class ChapterMutation {
     )
 
     @RequireAuth
-    fun setChapterMeta(input: SetChapterMetaInput): DataFetcherResult<SetChapterMetaPayload?> =
+    fun setChapterMeta(input: SetChapterMetaInput): DataFetcherResult<SetChapterMetaPayload> =
         asDataFetcherResult {
             val (clientMutationId, meta) = input
 
@@ -223,7 +223,7 @@ class ChapterMutation {
     )
 
     @RequireAuth
-    fun deleteChapterMeta(input: DeleteChapterMetaInput): DataFetcherResult<DeleteChapterMetaPayload?> =
+    fun deleteChapterMeta(input: DeleteChapterMetaInput): DataFetcherResult<DeleteChapterMetaPayload> =
         asDataFetcherResult {
             val (clientMutationId, chapterId, key) = input
 
@@ -269,7 +269,7 @@ class ChapterMutation {
     )
 
     @RequireAuth
-    fun setChapterMetas(input: SetChapterMetasInput): DataFetcherResult<SetChapterMetasPayload?> =
+    fun setChapterMetas(input: SetChapterMetasInput): DataFetcherResult<SetChapterMetasPayload> =
         asDataFetcherResult {
             val (clientMutationId, items) = input
 
@@ -325,7 +325,7 @@ class ChapterMutation {
     )
 
     @RequireAuth
-    fun deleteChapterMetas(input: DeleteChapterMetasInput): DataFetcherResult<DeleteChapterMetasPayload?> =
+    fun deleteChapterMetas(input: DeleteChapterMetasInput): DataFetcherResult<DeleteChapterMetasPayload> =
         asDataFetcherResult {
             val (clientMutationId, items) = input
 
@@ -405,7 +405,7 @@ class ChapterMutation {
     )
 
     @RequireAuth
-    fun fetchChapterPages(input: FetchChapterPagesInput): CompletableFuture<DataFetcherResult<FetchChapterPagesPayload?>> {
+    fun fetchChapterPages(input: FetchChapterPagesInput): CompletableFuture<DataFetcherResult<FetchChapterPagesPayload>> {
         val (clientMutationId, chapterId) = input
         val paramsMap = input.toParams()
 
diff --git a/server/src/main/kotlin/suwayomi/tachidesk/graphql/mutations/DownloadMutation.kt b/server/src/main/kotlin/suwayomi/tachidesk/graphql/mutations/DownloadMutation.kt
index 57e5dfdfa..53536cf87 100644
--- a/server/src/main/kotlin/suwayomi/tachidesk/graphql/mutations/DownloadMutation.kt
+++ b/server/src/main/kotlin/suwayomi/tachidesk/graphql/mutations/DownloadMutation.kt
@@ -30,7 +30,7 @@ class DownloadMutation {
     )
 
     @RequireAuth
-    fun deleteDownloadedChapters(input: DeleteDownloadedChaptersInput): DataFetcherResult<DeleteDownloadedChaptersPayload?> {
+    fun deleteDownloadedChapters(input: DeleteDownloadedChaptersInput): DataFetcherResult<DeleteDownloadedChaptersPayload> {
         val (clientMutationId, chapters) = input
 
         return asDataFetcherResult {
@@ -60,7 +60,7 @@ class DownloadMutation {
     )
 
     @RequireAuth
-    fun deleteDownloadedChapter(input: DeleteDownloadedChapterInput): DataFetcherResult<DeleteDownloadedChapterPayload?> {
+    fun deleteDownloadedChapter(input: DeleteDownloadedChapterInput): DataFetcherResult<DeleteDownloadedChapterPayload> {
         val (clientMutationId, chapter) = input
 
         return asDataFetcherResult {
@@ -89,7 +89,7 @@ class DownloadMutation {
     @RequireAuth
     fun enqueueChapterDownloads(
         input: EnqueueChapterDownloadsInput,
-    ): CompletableFuture<DataFetcherResult<EnqueueChapterDownloadsPayload?>> {
+    ): CompletableFuture<DataFetcherResult<EnqueueChapterDownloadsPayload>> {
         val (clientMutationId, chapters) = input
 
         return future {
@@ -123,7 +123,7 @@ class DownloadMutation {
     )
 
     @RequireAuth
-    fun enqueueChapterDownload(input: EnqueueChapterDownloadInput): CompletableFuture<DataFetcherResult<EnqueueChapterDownloadPayload?>> {
+    fun enqueueChapterDownload(input: EnqueueChapterDownloadInput): CompletableFuture<DataFetcherResult<EnqueueChapterDownloadPayload>> {
         val (clientMutationId, chapter) = input
 
         return future {
@@ -158,7 +158,7 @@ class DownloadMutation {
     @RequireAuth
     fun dequeueChapterDownloads(
         input: DequeueChapterDownloadsInput,
-    ): CompletableFuture<DataFetcherResult<DequeueChapterDownloadsPayload?>> {
+    ): CompletableFuture<DataFetcherResult<DequeueChapterDownloadsPayload>> {
         val (clientMutationId, chapters) = input
 
         return future {
@@ -194,7 +194,7 @@ class DownloadMutation {
     )
 
     @RequireAuth
-    fun dequeueChapterDownload(input: DequeueChapterDownloadInput): CompletableFuture<DataFetcherResult<DequeueChapterDownloadPayload?>> {
+    fun dequeueChapterDownload(input: DequeueChapterDownloadInput): CompletableFuture<DataFetcherResult<DequeueChapterDownloadPayload>> {
         val (clientMutationId, chapter) = input
 
         return future {
@@ -229,7 +229,7 @@ class DownloadMutation {
     )
 
     @RequireAuth
-    fun startDownloader(input: StartDownloaderInput): CompletableFuture<DataFetcherResult<StartDownloaderPayload?>> =
+    fun startDownloader(input: StartDownloaderInput): CompletableFuture<DataFetcherResult<StartDownloaderPayload>> =
         future {
             asDataFetcherResult {
                 DownloadManager.start()
@@ -258,7 +258,7 @@ class DownloadMutation {
     )
 
     @RequireAuth
-    fun stopDownloader(input: StopDownloaderInput): CompletableFuture<DataFetcherResult<StopDownloaderPayload?>> =
+    fun stopDownloader(input: StopDownloaderInput): CompletableFuture<DataFetcherResult<StopDownloaderPayload>> =
         future {
             asDataFetcherResult {
                 DownloadManager.stop()
@@ -287,7 +287,7 @@ class DownloadMutation {
     )
 
     @RequireAuth
-    fun clearDownloader(input: ClearDownloaderInput): CompletableFuture<DataFetcherResult<ClearDownloaderPayload?>> =
+    fun clearDownloader(input: ClearDownloaderInput): CompletableFuture<DataFetcherResult<ClearDownloaderPayload>> =
         future {
             asDataFetcherResult {
                 DownloadManager.clear()
@@ -318,7 +318,7 @@ class DownloadMutation {
     )
 
     @RequireAuth
-    fun reorderChapterDownload(input: ReorderChapterDownloadInput): CompletableFuture<DataFetcherResult<ReorderChapterDownloadPayload?>> {
+    fun reorderChapterDownload(input: ReorderChapterDownloadInput): CompletableFuture<DataFetcherResult<ReorderChapterDownloadPayload>> {
         val (clientMutationId, chapter, to) = input
 
         return future {
diff --git a/server/src/main/kotlin/suwayomi/tachidesk/graphql/mutations/ExtensionMutation.kt b/server/src/main/kotlin/suwayomi/tachidesk/graphql/mutations/ExtensionMutation.kt
index b484890cf..a813ca98c 100644
--- a/server/src/main/kotlin/suwayomi/tachidesk/graphql/mutations/ExtensionMutation.kt
+++ b/server/src/main/kotlin/suwayomi/tachidesk/graphql/mutations/ExtensionMutation.kt
@@ -75,7 +75,7 @@ class ExtensionMutation {
     }
 
     @RequireAuth
-    fun updateExtension(input: UpdateExtensionInput): CompletableFuture<DataFetcherResult<UpdateExtensionPayload?>> {
+    fun updateExtension(input: UpdateExtensionInput): CompletableFuture<DataFetcherResult<UpdateExtensionPayload>> {
         val (clientMutationId, id, patch) = input
 
         return future {
@@ -100,7 +100,7 @@ class ExtensionMutation {
     }
 
     @RequireAuth
-    fun updateExtensions(input: UpdateExtensionsInput): CompletableFuture<DataFetcherResult<UpdateExtensionsPayload?>> {
+    fun updateExtensions(input: UpdateExtensionsInput): CompletableFuture<DataFetcherResult<UpdateExtensionsPayload>> {
         val (clientMutationId, ids, patch) = input
 
         return future {
@@ -133,7 +133,7 @@ class ExtensionMutation {
     )
 
     @RequireAuth
-    fun fetchExtensions(input: FetchExtensionsInput): CompletableFuture<DataFetcherResult<FetchExtensionsPayload?>> {
+    fun fetchExtensions(input: FetchExtensionsInput): CompletableFuture<DataFetcherResult<FetchExtensionsPayload>> {
         val (clientMutationId) = input
 
         return future {
@@ -169,7 +169,7 @@ class ExtensionMutation {
     @RequireAuth
     fun installExternalExtension(
         input: InstallExternalExtensionInput,
-    ): CompletableFuture<DataFetcherResult<InstallExternalExtensionPayload?>> {
+    ): CompletableFuture<DataFetcherResult<InstallExternalExtensionPayload>> {
         val (clientMutationId, extensionFile) = input
 
         return future {
diff --git a/server/src/main/kotlin/suwayomi/tachidesk/graphql/mutations/InfoMutation.kt b/server/src/main/kotlin/suwayomi/tachidesk/graphql/mutations/InfoMutation.kt
index 519f6aa77..a75b9baa2 100644
--- a/server/src/main/kotlin/suwayomi/tachidesk/graphql/mutations/InfoMutation.kt
+++ b/server/src/main/kotlin/suwayomi/tachidesk/graphql/mutations/InfoMutation.kt
@@ -26,7 +26,7 @@ class InfoMutation {
     )
 
     @RequireAuth
-    fun updateWebUI(input: WebUIUpdateInput): CompletableFuture<DataFetcherResult<WebUIUpdatePayload?>> {
+    fun updateWebUI(input: WebUIUpdateInput): CompletableFuture<DataFetcherResult<WebUIUpdatePayload>> {
         return future {
             asDataFetcherResult {
                 withTimeout(30.seconds) {
@@ -62,7 +62,7 @@ class InfoMutation {
     }
 
     @RequireAuth
-    fun resetWebUIUpdateStatus(): CompletableFuture<DataFetcherResult<WebUIUpdateStatus?>> =
+    fun resetWebUIUpdateStatus(): CompletableFuture<DataFetcherResult<WebUIUpdateStatus>> =
         future {
             asDataFetcherResult {
                 withTimeout(30.seconds) {
diff --git a/server/src/main/kotlin/suwayomi/tachidesk/graphql/mutations/KoreaderSyncMutation.kt b/server/src/main/kotlin/suwayomi/tachidesk/graphql/mutations/KoreaderSyncMutation.kt
index e1ae1e4c5..b2de9b9e4 100644
--- a/server/src/main/kotlin/suwayomi/tachidesk/graphql/mutations/KoreaderSyncMutation.kt
+++ b/server/src/main/kotlin/suwayomi/tachidesk/graphql/mutations/KoreaderSyncMutation.kt
@@ -62,7 +62,7 @@ class KoreaderSyncMutation {
     )
 
     @RequireAuth
-    fun pushKoSyncProgress(input: PushKoSyncProgressInput): CompletableFuture<DataFetcherResult<PushKoSyncProgressPayload?>> =
+    fun pushKoSyncProgress(input: PushKoSyncProgressInput): CompletableFuture<DataFetcherResult<PushKoSyncProgressPayload>> =
         future {
             asDataFetcherResult {
                 KoreaderSyncService.pushProgress(input.chapterId)
@@ -96,7 +96,7 @@ class KoreaderSyncMutation {
     )
 
     @RequireAuth
-    fun pullKoSyncProgress(input: PullKoSyncProgressInput): CompletableFuture<DataFetcherResult<PullKoSyncProgressPayload?>> =
+    fun pullKoSyncProgress(input: PullKoSyncProgressInput): CompletableFuture<DataFetcherResult<PullKoSyncProgressPayload>> =
         future {
             asDataFetcherResult {
                 val syncResult = KoreaderSyncService.checkAndPullProgress(input.chapterId)
diff --git a/server/src/main/kotlin/suwayomi/tachidesk/graphql/mutations/MangaMutation.kt b/server/src/main/kotlin/suwayomi/tachidesk/graphql/mutations/MangaMutation.kt
index 175c790ff..8be3be9af 100644
--- a/server/src/main/kotlin/suwayomi/tachidesk/graphql/mutations/MangaMutation.kt
+++ b/server/src/main/kotlin/suwayomi/tachidesk/graphql/mutations/MangaMutation.kt
@@ -98,7 +98,7 @@ class MangaMutation {
     }
 
     @RequireAuth
-    fun updateManga(input: UpdateMangaInput): CompletableFuture<DataFetcherResult<UpdateMangaPayload?>> {
+    fun updateManga(input: UpdateMangaInput): CompletableFuture<DataFetcherResult<UpdateMangaPayload>> {
         val (clientMutationId, id, patch) = input
 
         return future {
@@ -119,7 +119,7 @@ class MangaMutation {
     }
 
     @RequireAuth
-    fun updateMangas(input: UpdateMangasInput): CompletableFuture<DataFetcherResult<UpdateMangasPayload?>> {
+    fun updateMangas(input: UpdateMangasInput): CompletableFuture<DataFetcherResult<UpdateMangasPayload>> {
         val (clientMutationId, ids, patch) = input
 
         return future {
@@ -150,7 +150,7 @@ class MangaMutation {
     )
 
     @RequireAuth
-    fun fetchManga(input: FetchMangaInput): CompletableFuture<DataFetcherResult<FetchMangaPayload?>> {
+    fun fetchManga(input: FetchMangaInput): CompletableFuture<DataFetcherResult<FetchMangaPayload>> {
         val (clientMutationId, id) = input
 
         return future {
@@ -180,7 +180,7 @@ class MangaMutation {
     )
 
     @RequireAuth
-    fun setMangaMeta(input: SetMangaMetaInput): DataFetcherResult<SetMangaMetaPayload?> {
+    fun setMangaMeta(input: SetMangaMetaInput): DataFetcherResult<SetMangaMetaPayload> {
         val (clientMutationId, meta) = input
 
         return asDataFetcherResult {
@@ -203,7 +203,7 @@ class MangaMutation {
     )
 
     @RequireAuth
-    fun deleteMangaMeta(input: DeleteMangaMetaInput): DataFetcherResult<DeleteMangaMetaPayload?> {
+    fun deleteMangaMeta(input: DeleteMangaMetaInput): DataFetcherResult<DeleteMangaMetaPayload> {
         val (clientMutationId, mangaId, key) = input
 
         return asDataFetcherResult {
@@ -250,7 +250,7 @@ class MangaMutation {
     )
 
     @RequireAuth
-    fun setMangaMetas(input: SetMangaMetasInput): DataFetcherResult<SetMangaMetasPayload?> {
+    fun setMangaMetas(input: SetMangaMetasInput): DataFetcherResult<SetMangaMetasPayload> {
         val (clientMutationId, items) = input
 
         return asDataFetcherResult {
@@ -307,7 +307,7 @@ class MangaMutation {
     )
 
     @RequireAuth
-    fun deleteMangaMetas(input: DeleteMangaMetasInput): DataFetcherResult<DeleteMangaMetasPayload?> {
+    fun deleteMangaMetas(input: DeleteMangaMetasInput): DataFetcherResult<DeleteMangaMetasPayload> {
         val (clientMutationId, items) = input
 
         return asDataFetcherResult {
diff --git a/server/src/main/kotlin/suwayomi/tachidesk/graphql/mutations/MetaMutation.kt b/server/src/main/kotlin/suwayomi/tachidesk/graphql/mutations/MetaMutation.kt
index f29265283..64ae1d5b0 100644
--- a/server/src/main/kotlin/suwayomi/tachidesk/graphql/mutations/MetaMutation.kt
+++ b/server/src/main/kotlin/suwayomi/tachidesk/graphql/mutations/MetaMutation.kt
@@ -29,7 +29,7 @@ class MetaMutation {
     )
 
     @RequireAuth
-    fun setGlobalMeta(input: SetGlobalMetaInput): DataFetcherResult<SetGlobalMetaPayload?> {
+    fun setGlobalMeta(input: SetGlobalMetaInput): DataFetcherResult<SetGlobalMetaPayload> {
         val (clientMutationId, meta) = input
 
         return asDataFetcherResult {
@@ -50,7 +50,7 @@ class MetaMutation {
     )
 
     @RequireAuth
-    fun deleteGlobalMeta(input: DeleteGlobalMetaInput): DataFetcherResult<DeleteGlobalMetaPayload?> {
+    fun deleteGlobalMeta(input: DeleteGlobalMetaInput): DataFetcherResult<DeleteGlobalMetaPayload> {
         val (clientMutationId, key) = input
 
         return asDataFetcherResult {
@@ -86,7 +86,7 @@ class MetaMutation {
     )
 
     @RequireAuth
-    fun setGlobalMetas(input: SetGlobalMetasInput): DataFetcherResult<SetGlobalMetasPayload?> {
+    fun setGlobalMetas(input: SetGlobalMetasInput): DataFetcherResult<SetGlobalMetasPayload> {
         val (clientMutationId, metas) = input
 
         return asDataFetcherResult {
@@ -117,7 +117,7 @@ class MetaMutation {
     )
 
     @RequireAuth
-    fun deleteGlobalMetas(input: DeleteGlobalMetasInput): DataFetcherResult<DeleteGlobalMetasPayload?> {
+    fun deleteGlobalMetas(input: DeleteGlobalMetasInput): DataFetcherResult<DeleteGlobalMetasPayload> {
         val (clientMutationId, keys, prefixes) = input
 
         return asDataFetcherResult {
diff --git a/server/src/main/kotlin/suwayomi/tachidesk/graphql/mutations/SourceMutation.kt b/server/src/main/kotlin/suwayomi/tachidesk/graphql/mutations/SourceMutation.kt
index c9b619e77..0cb9fff3b 100644
--- a/server/src/main/kotlin/suwayomi/tachidesk/graphql/mutations/SourceMutation.kt
+++ b/server/src/main/kotlin/suwayomi/tachidesk/graphql/mutations/SourceMutation.kt
@@ -47,7 +47,7 @@ class SourceMutation {
     )
 
     @RequireAuth
-    fun setSourceMeta(input: SetSourceMetaInput): DataFetcherResult<SetSourceMetaPayload?> {
+    fun setSourceMeta(input: SetSourceMetaInput): DataFetcherResult<SetSourceMetaPayload> {
         val (clientMutationId, meta) = input
 
         return asDataFetcherResult {
@@ -70,7 +70,7 @@ class SourceMutation {
     )
 
     @RequireAuth
-    fun deleteSourceMeta(input: DeleteSourceMetaInput): DataFetcherResult<DeleteSourceMetaPayload?> {
+    fun deleteSourceMeta(input: DeleteSourceMetaInput): DataFetcherResult<DeleteSourceMetaPayload> {
         val (clientMutationId, sourceId, key) = input
 
         return asDataFetcherResult {
@@ -121,7 +121,7 @@ class SourceMutation {
     )
 
     @RequireAuth
-    fun setSourceMetas(input: SetSourceMetasInput): DataFetcherResult<SetSourceMetasPayload?> {
+    fun setSourceMetas(input: SetSourceMetasInput): DataFetcherResult<SetSourceMetasPayload> {
         val (clientMutationId, items) = input
 
         return asDataFetcherResult {
@@ -178,7 +178,7 @@ class SourceMutation {
     )
 
     @RequireAuth
-    fun deleteSourceMetas(input: DeleteSourceMetasInput): DataFetcherResult<DeleteSourceMetasPayload?> {
+    fun deleteSourceMetas(input: DeleteSourceMetasInput): DataFetcherResult<DeleteSourceMetasPayload> {
         val (clientMutationId, items) = input
 
         return asDataFetcherResult {
@@ -260,7 +260,7 @@ class SourceMutation {
     )
 
     @RequireAuth
-    fun fetchSourceManga(input: FetchSourceMangaInput): CompletableFuture<DataFetcherResult<FetchSourceMangaPayload?>> {
+    fun fetchSourceManga(input: FetchSourceMangaInput): CompletableFuture<DataFetcherResult<FetchSourceMangaPayload>> {
         val (clientMutationId, sourceId, type, page, query, filters) = input
 
         return future {
@@ -329,7 +329,7 @@ class SourceMutation {
     )
 
     @RequireAuth
-    fun updateSourcePreference(input: UpdateSourcePreferenceInput): DataFetcherResult<UpdateSourcePreferencePayload?> {
+    fun updateSourcePreference(input: UpdateSourcePreferenceInput): DataFetcherResult<UpdateSourcePreferencePayload> {
         val (clientMutationId, sourceId, change) = input
 
         return asDataFetcherResult {
diff --git a/server/src/main/kotlin/suwayomi/tachidesk/graphql/mutations/TrackMutation.kt b/server/src/main/kotlin/suwayomi/tachidesk/graphql/mutations/TrackMutation.kt
index ac6181339..207d8eb82 100644
--- a/server/src/main/kotlin/suwayomi/tachidesk/graphql/mutations/TrackMutation.kt
+++ b/server/src/main/kotlin/suwayomi/tachidesk/graphql/mutations/TrackMutation.kt
@@ -222,7 +222,7 @@ class TrackMutation {
     )
 
     @RequireAuth
-    fun trackProgress(input: TrackProgressInput): CompletableFuture<DataFetcherResult<TrackProgressPayload?>> {
+    fun trackProgress(input: TrackProgressInput): CompletableFuture<DataFetcherResult<TrackProgressPayload>> {
         val (clientMutationId, mangaId) = input
 
         return future {
diff --git a/server/src/main/kotlin/suwayomi/tachidesk/graphql/mutations/UpdateMutation.kt b/server/src/main/kotlin/suwayomi/tachidesk/graphql/mutations/UpdateMutation.kt
index d8cbaa761..e2a125af3 100644
--- a/server/src/main/kotlin/suwayomi/tachidesk/graphql/mutations/UpdateMutation.kt
+++ b/server/src/main/kotlin/suwayomi/tachidesk/graphql/mutations/UpdateMutation.kt
@@ -28,7 +28,7 @@ class UpdateMutation {
     )
 
     @RequireAuth
-    fun updateLibrary(input: UpdateLibraryInput): CompletableFuture<DataFetcherResult<UpdateLibraryPayload?>> {
+    fun updateLibrary(input: UpdateLibraryInput): CompletableFuture<DataFetcherResult<UpdateLibraryPayload>> {
         updater.addCategoriesToUpdateQueue(
             Category.getCategoryList().filter { input.categories?.contains(it.id) ?: true },
             clear = true,
@@ -60,7 +60,7 @@ class UpdateMutation {
     )
 
     @RequireAuth
-    fun updateLibraryManga(input: UpdateLibraryMangaInput): CompletableFuture<DataFetcherResult<UpdateLibraryMangaPayload?>> {
+    fun updateLibraryManga(input: UpdateLibraryMangaInput): CompletableFuture<DataFetcherResult<UpdateLibraryMangaPayload>> {
         updateLibrary(
             UpdateLibraryInput(
                 clientMutationId = input.clientMutationId,
@@ -92,7 +92,7 @@ class UpdateMutation {
     )
 
     @RequireAuth
-    fun updateCategoryManga(input: UpdateCategoryMangaInput): CompletableFuture<DataFetcherResult<UpdateCategoryMangaPayload?>> {
+    fun updateCategoryManga(input: UpdateCategoryMangaInput): CompletableFuture<DataFetcherResult<UpdateCategoryMangaPayload>> {
         updateLibrary(
             UpdateLibraryInput(
                 clientMutationId = input.clientMutationId,
diff --git a/server/src/main/kotlin/suwayomi/tachidesk/graphql/server/JavalinGraphQLRequestParser.kt b/server/src/main/kotlin/suwayomi/tachidesk/graphql/server/JavalinGraphQLRequestParser.kt
index e8fefcb9a..f07d99629 100644
--- a/server/src/main/kotlin/suwayomi/tachidesk/graphql/server/JavalinGraphQLRequestParser.kt
+++ b/server/src/main/kotlin/suwayomi/tachidesk/graphql/server/JavalinGraphQLRequestParser.kt
@@ -11,6 +11,7 @@ import com.expediagroup.graphql.server.execution.GraphQLRequestParser
 import com.expediagroup.graphql.server.types.GraphQLBatchRequest
 import com.expediagroup.graphql.server.types.GraphQLRequest
 import com.expediagroup.graphql.server.types.GraphQLServerRequest
+import io.github.oshai.kotlinlogging.KotlinLogging
 import io.javalin.http.Context
 import io.javalin.http.UploadedFile
 import io.javalin.json.JavalinJackson
@@ -19,11 +20,12 @@ import io.javalin.json.fromJsonString
 import java.io.IOException
 
 class JavalinGraphQLRequestParser : GraphQLRequestParser<Context> {
-    val jsonMapper = JavalinJackson()
+    private val logger = KotlinLogging.logger {}
 
     @Suppress("PARAMETER_NAME_CHANGED_ON_OVERRIDE")
     override suspend fun parseRequest(context: Context): GraphQLServerRequest? {
         return try {
+            val jsonMapper = context.jsonMapper()
             val contentType = context.contentType()
             val formParam =
                 if (
@@ -77,7 +79,8 @@ class JavalinGraphQLRequestParser : GraphQLRequestParser<Context> {
                     )
                 }
             }
-        } catch (_: IOException) {
+        } catch (e: IOException) {
+            logger.error(e) { "Error when parsing request" }
             null
         }
     }
diff --git a/server/src/main/kotlin/suwayomi/tachidesk/graphql/server/TachideskGraphQLServer.kt b/server/src/main/kotlin/suwayomi/tachidesk/graphql/server/TachideskGraphQLServer.kt
index fbfd6945e..0b640b5e1 100644
--- a/server/src/main/kotlin/suwayomi/tachidesk/graphql/server/TachideskGraphQLServer.kt
+++ b/server/src/main/kotlin/suwayomi/tachidesk/graphql/server/TachideskGraphQLServer.kt
@@ -10,7 +10,6 @@ package suwayomi.tachidesk.graphql.server
 import com.expediagroup.graphql.generator.execution.FlowSubscriptionExecutionStrategy
 import com.expediagroup.graphql.server.execution.GraphQLRequestHandler
 import com.expediagroup.graphql.server.execution.GraphQLServer
-import com.fasterxml.jackson.module.kotlin.jacksonObjectMapper
 import graphql.ExceptionWhileDataFetching
 import graphql.GraphQL
 import graphql.execution.AsyncExecutionStrategy
@@ -27,6 +26,7 @@ import kotlinx.coroutines.flow.launchIn
 import kotlinx.coroutines.flow.map
 import suwayomi.tachidesk.graphql.server.subscriptions.ApolloSubscriptionProtocolHandler
 import suwayomi.tachidesk.server.JavalinSetup.future
+import tools.jackson.module.kotlin.jacksonObjectMapper
 
 class TachideskGraphQLServer(
     requestParser: JavalinGraphQLRequestParser,
diff --git a/server/src/main/kotlin/suwayomi/tachidesk/graphql/server/primitives/Cursor.kt b/server/src/main/kotlin/suwayomi/tachidesk/graphql/server/primitives/Cursor.kt
index 413c23ddf..7029663c1 100644
--- a/server/src/main/kotlin/suwayomi/tachidesk/graphql/server/primitives/Cursor.kt
+++ b/server/src/main/kotlin/suwayomi/tachidesk/graphql/server/primitives/Cursor.kt
@@ -58,7 +58,7 @@ private class GraphqlCursorCoercing : Coercing<Cursor, String> {
                 ),
             )
         }
-        return Cursor(input.value)
+        return Cursor(input.value!!)
     }
 
     private fun valueToLiteralImpl(input: Any): StringValue = StringValue.newStringValue(input.toString()).build()
diff --git a/server/src/main/kotlin/suwayomi/tachidesk/graphql/server/primitives/DurationAsString.kt b/server/src/main/kotlin/suwayomi/tachidesk/graphql/server/primitives/DurationAsString.kt
index 3469900a2..633ed85b0 100644
--- a/server/src/main/kotlin/suwayomi/tachidesk/graphql/server/primitives/DurationAsString.kt
+++ b/server/src/main/kotlin/suwayomi/tachidesk/graphql/server/primitives/DurationAsString.kt
@@ -71,7 +71,7 @@ private class GraphqlDurationAsStringCoercing : Coercing<Duration, String> {
             )
         }
         return try {
-            Duration.parse(input.value)
+            Duration.parse(input.value!!)
         } catch (e: IllegalArgumentException) {
             throw CoercingParseLiteralException(
                 "Invalid duration format: ${input.value}. Expected ISO-8601 duration string (e.g., 'PT30M', 'P1D')",
diff --git a/server/src/main/kotlin/suwayomi/tachidesk/graphql/server/primitives/LongAsString.kt b/server/src/main/kotlin/suwayomi/tachidesk/graphql/server/primitives/LongAsString.kt
index 651c4fb80..6563c08f6 100644
--- a/server/src/main/kotlin/suwayomi/tachidesk/graphql/server/primitives/LongAsString.kt
+++ b/server/src/main/kotlin/suwayomi/tachidesk/graphql/server/primitives/LongAsString.kt
@@ -53,7 +53,7 @@ private class GraphqlLongAsStringCoercing : Coercing<Long, String> {
                 ),
             )
         }
-        return input.value.toLong()
+        return input.value!!.toLong()
     }
 
     private fun valueToLiteralImpl(input: Any): StringValue = StringValue.newStringValue(input.toString()).build()
diff --git a/server/src/main/kotlin/suwayomi/tachidesk/graphql/server/subscriptions/ApolloSubscriptionProtocolHandler.kt b/server/src/main/kotlin/suwayomi/tachidesk/graphql/server/subscriptions/ApolloSubscriptionProtocolHandler.kt
index aea05df0f..72ec0b7da 100644
--- a/server/src/main/kotlin/suwayomi/tachidesk/graphql/server/subscriptions/ApolloSubscriptionProtocolHandler.kt
+++ b/server/src/main/kotlin/suwayomi/tachidesk/graphql/server/subscriptions/ApolloSubscriptionProtocolHandler.kt
@@ -9,9 +9,6 @@ package suwayomi.tachidesk.graphql.server.subscriptions
 
 import com.expediagroup.graphql.server.execution.GraphQLRequestHandler
 import com.expediagroup.graphql.server.types.GraphQLRequest
-import com.fasterxml.jackson.databind.ObjectMapper
-import com.fasterxml.jackson.module.kotlin.convertValue
-import com.fasterxml.jackson.module.kotlin.readValue
 import io.github.oshai.kotlinlogging.KotlinLogging
 import io.javalin.http.Header
 import io.javalin.websocket.WsContext
@@ -41,6 +38,9 @@ import suwayomi.tachidesk.server.JavalinSetup.Attribute
 import suwayomi.tachidesk.server.JavalinSetup.getAttributeOrSet
 import suwayomi.tachidesk.server.user.UserType
 import suwayomi.tachidesk.server.user.getUserFromToken
+import tools.jackson.databind.ObjectMapper
+import tools.jackson.module.kotlin.convertValue
+import tools.jackson.module.kotlin.readValue
 
 /**
  * Implementation of the `graphql-transport-ws` protocol defined by Denis Badurina