diff --git a/src/main/kotlin/ru/dbotthepony/kstarbound/io/KConcreteTypeAdapter.kt b/src/main/kotlin/ru/dbotthepony/kstarbound/io/KConcreteTypeAdapter.kt
index 5580d987..009098f5 100644
--- a/src/main/kotlin/ru/dbotthepony/kstarbound/io/KConcreteTypeAdapter.kt
+++ b/src/main/kotlin/ru/dbotthepony/kstarbound/io/KConcreteTypeAdapter.kt
@@ -38,16 +38,18 @@ private fun <T> resolveBound(bound: Class<T>, stringAdapter: TypeAdapter<String>
 	}
 }
 
-private class ListAdapter<T>(private val bound: Class<T>, private val stringAdapter: TypeAdapter<String>) : TypeAdapter<List<T>>() {
+private class ListAdapter<T>(private val bound: Class<T>, private val stringAdapter: TypeAdapter<String>) : TypeAdapter<List<T>?>() {
 	private val resolvedBound by lazy { resolveBound(bound, stringAdapter) }
 
-	override fun write(out: JsonWriter, value: List<T>) {
+	override fun write(out: JsonWriter, value: List<T>?) {
 		out.beginArray()
 
-		val resolvedBound = resolvedBound
+		if (value != null) {
+			val resolvedBound = resolvedBound
 
-		for (v in value) {
-			resolvedBound.write(out, v)
+			for (v in value) {
+				resolvedBound.write(out, v)
+			}
 		}
 
 		out.endArray()
@@ -70,21 +72,23 @@ private class ListAdapter<T>(private val bound: Class<T>, private val stringAdap
 	}
 }
 
-private class MapAdapter<K, V>(private val boundKey: Class<K>, private val boundValue: Class<V>, private val stringAdapter: TypeAdapter<String>) : TypeAdapter<Map<K, V>>() {
+private class MapAdapter<K, V>(private val boundKey: Class<K>, private val boundValue: Class<V>, private val stringAdapter: TypeAdapter<String>) : TypeAdapter<Map<K, V>?>() {
 	private val resolvedKey by lazy { resolveBound(boundKey, stringAdapter) }
 	private val resolvedValue by lazy { resolveBound(boundValue, stringAdapter) }
 
-	override fun write(out: JsonWriter, value: Map<K, V>) {
+	override fun write(out: JsonWriter, value: Map<K, V>?) {
 		out.beginArray()
 
-		val resolvedKey = resolvedKey
-		val resolvedValue = resolvedValue
+		if (value != null) {
+			val resolvedKey = resolvedKey
+			val resolvedValue = resolvedValue
 
-		for ((k, v) in value) {
-			out.beginArray()
-			resolvedKey.write(out, k)
-			resolvedValue.write(out, v)
-			out.endArray()
+			for ((k, v) in value) {
+				out.beginArray()
+				resolvedKey.write(out, k)
+				resolvedValue.write(out, v)
+				out.endArray()
+			}
 		}
 
 		out.endArray()
@@ -110,17 +114,19 @@ private class MapAdapter<K, V>(private val boundKey: Class<K>, private val bound
 	}
 }
 
-private class StringMapAdapter<V>(private val bound: Class<V>, private val stringAdapter: TypeAdapter<String>, private val interner: () -> Interner<String>) : TypeAdapter<Map<String, V>>() {
+private class StringMapAdapter<V>(private val bound: Class<V>, private val stringAdapter: TypeAdapter<String>, private val interner: () -> Interner<String>) : TypeAdapter<Map<String, V>?>() {
 	private val resolvedBound by lazy { resolveBound(bound, stringAdapter) }
 
-	override fun write(out: JsonWriter, value: Map<String, V>) {
+	override fun write(out: JsonWriter, value: Map<String, V>?) {
 		val resolvedBound = resolvedBound
 
 		out.beginObject()
 
-		for ((k, v) in value) {
-			out.name(k)
-			resolvedBound.write(out, v)
+		if (value != null) {
+			for ((k, v) in value) {
+				out.name(k)
+				resolvedBound.write(out, v)
+			}
 		}
 
 		out.endObject()
@@ -155,15 +161,22 @@ private class LazyTypeProvider<T : Any?>(private val bound: Class<T>) : TypeAdap
 	}
 }
 
+private data class PackedProperty<Clazz : Any, T>(
+	val property: KProperty1<Clazz, T>,
+	val adapter: TypeAdapter<T>,
+	val transformer: (T) -> T = { it }
+) {
+	val returnType = property.returnType
+}
+
 /**
  * TypeAdapter для классов которые создаются единожды и более не меняются ("бетонных классов").
  */
-class KConcreteTypeAdapter<T : Any>(
+class KConcreteTypeAdapter<T : Any> private constructor(
 	val bound: KClass<T>,
-	val types: ImmutableList<Pair<KProperty1<T, *>, TypeAdapter<*>>>,
-	val asList: Boolean = false
+	private val types: ImmutableList<PackedProperty<T, *>>,
+	private val asJsonArray: Boolean = false
 ) : TypeAdapter<T>() {
-	private val returnTypeCache = Object2ObjectArrayMap<KProperty1<T, *>, KType>()
 	private val mapped = Object2IntArrayMap<String>()
 	private val internedStrings = Interners.newWeakInterner<String>()
 	private val loggedMisses = ObjectArraySet<String>()
@@ -171,14 +184,10 @@ class KConcreteTypeAdapter<T : Any>(
 	var currentSymbolicName by ThreadLocal<String>()
 
 	init {
-		for ((field) in types) {
-			returnTypeCache[field] = field.returnType
-		}
-
 		mapped.defaultReturnValue(-1)
 
 		for ((i, pair) in types.withIndex()) {
-			mapped[pair.first.name] = i
+			mapped[pair.property.name] = i
 		}
 	}
 
@@ -193,7 +202,7 @@ class KConcreteTypeAdapter<T : Any>(
 				val nextParam = iterator.next()
 
 				val a = param.type
-				val b = nextParam.first.returnType
+				val b = nextParam.returnType
 
 				if (!a.isSupertypeOf(b) || a.isMarkedNullable != b.isMarkedNullable) {
 					return@first false
@@ -210,7 +219,7 @@ class KConcreteTypeAdapter<T : Any>(
 	 * Синтетический конструктор класса, который создаётся Kotlin'ном, для создания классов со значениями по умолчанию
 	 */
 	private val syntheticFactory: Constructor<T>? = try {
-		bound.java.getDeclaredConstructor(*types.map { (it.first.returnType.classifier as KClass<*>).java }.also {
+		bound.java.getDeclaredConstructor(*types.map { (it.returnType.classifier as KClass<*>).java }.also {
 			it as MutableList
 			it.add(Int::class.java)
 			it.add(DefaultConstructorMarker::class.java)
@@ -260,7 +269,7 @@ class KConcreteTypeAdapter<T : Any>(
 	}
 
 	override fun read(reader: JsonReader): T {
-		if (asList) {
+		if (asJsonArray) {
 			reader.beginArray()
 		} else {
 			reader.beginObject()
@@ -271,7 +280,7 @@ class KConcreteTypeAdapter<T : Any>(
 		val readValues = arrayOfNulls<Any>(types.size)
 
 		// Если нам необходимо читать объект как набор данных массива, то давай
-		if (asList) {
+		if (asJsonArray) {
 			val iterator = types.iterator()
 			var fieldId = 0
 
@@ -344,7 +353,7 @@ class KConcreteTypeAdapter<T : Any>(
 			}
 		}
 
-		if (asList) {
+		if (asJsonArray) {
 			reader.endArray()
 		} else {
 			reader.endObject()
@@ -353,11 +362,11 @@ class KConcreteTypeAdapter<T : Any>(
 		// если у нас есть все значения для конструктора (все значения присутствуют в исходном json объекте)
 		// или у нас нет синтетического конструктора, то делаем вызов "обычного" конструктора
 		if (syntheticFactory == null || presentValues.all { it }) {
-			for ((i, pair) in types.withIndex()) {
-				val (field) = pair
+			for ((i, tuple) in types.withIndex()) {
+				val (field) = tuple
 
 				if (readValues[i] == null) {
-					if (!returnTypeCache[field]!!.isMarkedNullable) {
+					if (!tuple.returnType.isMarkedNullable) {
 						throw JsonSyntaxException("Field ${field.name} of ${bound.qualifiedName} does not accept nulls")
 					}
 
@@ -399,19 +408,19 @@ class KConcreteTypeAdapter<T : Any>(
 
 			val syntheticPrimitives = syntheticPrimitives!!
 
-			for ((i, pair) in types.withIndex()) {
+			for ((i, tuple) in types.withIndex()) {
 				if (copied[i] != null) {
 					continue
 				}
 
-				val (field) = pair
+				val (field) = tuple
 				val param = regularFactory.parameters[i]
 
 				if (!param.isOptional && !presentValues[i]) {
 					throw JsonSyntaxException("Field ${field.name} of ${bound.qualifiedName} is missing")
 				}
 
-				if (returnTypeCache[field]!!.isMarkedNullable) {
+				if (tuple.returnType.isMarkedNullable) {
 					continue
 				}
 
@@ -431,7 +440,7 @@ class KConcreteTypeAdapter<T : Any>(
 	 * Позволяет построить класс [KConcreteTypeAdapter] на основе заданных параметров
 	 */
 	class Builder<T : Any>(val clazz: KClass<T>) {
-		private val types = ArrayList<Pair<KProperty1<T, *>, TypeAdapter<*>>>()
+		private val types = ArrayList<PackedProperty<T, *>>()
 		private var interner by Delegates.notNull<Interner<String>>()
 
 		private val internedStringAdapter: TypeAdapter<String> = object : TypeAdapter<String>() {
@@ -448,32 +457,33 @@ class KConcreteTypeAdapter<T : Any>(
 		 * Добавляет поле с определённым адаптером
 		 */
 		fun <V> plain(field: KProperty1<T, V>, adapter: TypeAdapter<V>): Builder<T> {
-			types.add(field to adapter)
+			types.add(PackedProperty(field, adapter))
 			return this
 		}
 
 		/**
 		 * Добавляет поле(я) без generic типов и без преобразователей
 		 */
+		@Suppress("unchecked_cast")
 		fun plain(vararg fields: KProperty1<T, *>): Builder<T> {
 			for (field in fields) {
 				val returnType = field.returnType
 				val classifier = returnType.classifier as? KClass<*> ?: throw ClassCastException("Unable to cast ${returnType.classifier} to KClass of property ${field.name}!")
 
 				if (classifier.isSuperclassOf(Float::class)) {
-					types.add(field to TypeAdapters.FLOAT)
+					types.add(PackedProperty(field as KProperty1<T, Float>, TypeAdapters.FLOAT))
 				} else if (classifier.isSuperclassOf(Double::class)) {
-					types.add(field to TypeAdapters.DOUBLE)
+					types.add(PackedProperty(field as KProperty1<T, Double>, TypeAdapters.DOUBLE))
 				} else if (classifier.isSuperclassOf(Int::class)) {
-					types.add(field to TypeAdapters.INTEGER)
+					types.add(PackedProperty(field as KProperty1<T, Int>, TypeAdapters.INTEGER))
 				} else if (classifier.isSuperclassOf(Long::class)) {
-					types.add(field to TypeAdapters.LONG)
+					types.add(PackedProperty(field as KProperty1<T, Long>, TypeAdapters.LONG))
 				} else if (classifier.isSuperclassOf(String::class)) {
-					types.add(field to internedStringAdapter)
+					types.add(PackedProperty(field as KProperty1<T, String>, internedStringAdapter))
 				} else if (classifier.isSuperclassOf(Boolean::class)) {
-					types.add(field to TypeAdapters.BOOLEAN)
+					types.add(PackedProperty(field as KProperty1<T, Boolean>, TypeAdapters.BOOLEAN))
 				} else {
-					types.add(field to LazyTypeProvider(classifier.java))
+					types.add(PackedProperty(field, LazyTypeProvider(classifier.java) as TypeAdapter<Any?>))
 				}
 			}
 
@@ -500,7 +510,7 @@ class KConcreteTypeAdapter<T : Any>(
 		 * Список неизменяем (создаётся объект [ImmutableList])
 		 */
 		fun <V : Any> list(field: KProperty1<T, List<V>?>, type: Class<V>): Builder<T> {
-			types.add(field to ListAdapter(type, internedStringAdapter))
+			types.add(PackedProperty(field, ListAdapter(type, internedStringAdapter)))
 			return this
 		}
 
@@ -519,7 +529,7 @@ class KConcreteTypeAdapter<T : Any>(
 		 * Таблица неизменяема (создаётся объект [ImmutableMap])
 		 */
 		fun <K, V> map(field: KProperty1<T, Map<K, V>>, keyType: Class<K>, valueType: Class<V>): Builder<T> {
-			types.add(field to MapAdapter(keyType, valueType, internedStringAdapter))
+			types.add(PackedProperty(field, MapAdapter(keyType, valueType, internedStringAdapter)))
 			return this
 		}
 
@@ -529,7 +539,7 @@ class KConcreteTypeAdapter<T : Any>(
 		 * Таблица неизменяема (создаётся объект [ImmutableMap])
 		 */
 		fun <K : Any, V : Any> map(field: KProperty1<T, Map<K, V>?>, keyType: KClass<K>, valueType: KClass<V>): Builder<T> {
-			types.add(field to MapAdapter(keyType.java, valueType.java, internedStringAdapter))
+			types.add(PackedProperty(field, MapAdapter(keyType.java, valueType.java, internedStringAdapter)))
 			return this
 		}
 
@@ -539,7 +549,7 @@ class KConcreteTypeAdapter<T : Any>(
 		 * Таблица неизменяема (создаётся объект [ImmutableMap])
 		 */
 		fun <V> map(field: KProperty1<T, Map<String, V>?>, valueType: Class<V>): Builder<T> {
-			types.add(field to StringMapAdapter(valueType, internedStringAdapter, ::interner))
+			types.add(PackedProperty(field, StringMapAdapter(valueType, internedStringAdapter, ::interner)))
 			return this
 		}
 
@@ -549,12 +559,12 @@ class KConcreteTypeAdapter<T : Any>(
 		 * Таблица неизменяема (создаётся объект [ImmutableMap])
 		 */
 		fun <V : Any> map(field: KProperty1<T, Map<String, V>?>, valueType: KClass<V>): Builder<T> {
-			types.add(field to StringMapAdapter(valueType.java, internedStringAdapter, ::interner))
+			types.add(PackedProperty(field, StringMapAdapter(valueType.java, internedStringAdapter, ::interner)))
 			return this
 		}
 
 		fun build(asList: Boolean = false): KConcreteTypeAdapter<T> {
-			return KConcreteTypeAdapter(clazz, ImmutableList.copyOf(types), asList = asList).also {
+			return KConcreteTypeAdapter(clazz, ImmutableList.copyOf(types), asJsonArray = asList).also {
 				interner = it.internedStrings
 			}
 		}