diff --git a/editor/src/main/kotlin/com/bartlomiejpluta/base/editor/main/view/MainView.kt b/editor/src/main/kotlin/com/bartlomiejpluta/base/editor/main/view/MainView.kt
index ae769b9b..e202a130 100644
--- a/editor/src/main/kotlin/com/bartlomiejpluta/base/editor/main/view/MainView.kt
+++ b/editor/src/main/kotlin/com/bartlomiejpluta/base/editor/main/view/MainView.kt
@@ -30,7 +30,7 @@ class MainView : View("BASE Game Editor") {
             Tab().apply {
                val vm = GameMapVM(map)
                setInScope(vm, scope)
-               projectContext.project?.maps?.get(map.uid)?.let { textProperty().bindBidirectional(it.nameProperty) }
+               projectContext.project?.maps?.first { it.uid == map.uid }?.let { textProperty().bindBidirectional(it.nameProperty) }
                content = find<MapFragment>(scope).root
                setOnClosed { mainController.openMaps.remove(scope) }
             }
diff --git a/editor/src/main/kotlin/com/bartlomiejpluta/base/editor/main/view/ProjectStructureView.kt b/editor/src/main/kotlin/com/bartlomiejpluta/base/editor/main/view/ProjectStructureView.kt
index b2796970..4b716223 100644
--- a/editor/src/main/kotlin/com/bartlomiejpluta/base/editor/main/view/ProjectStructureView.kt
+++ b/editor/src/main/kotlin/com/bartlomiejpluta/base/editor/main/view/ProjectStructureView.kt
@@ -3,6 +3,7 @@ package com.bartlomiejpluta.base.editor.main.view
 import com.bartlomiejpluta.base.editor.map.asset.GameMapAsset
 import com.bartlomiejpluta.base.editor.project.context.ProjectContext
 import com.bartlomiejpluta.base.editor.util.fx.BindingUtil
+import javafx.beans.binding.Bindings
 import javafx.beans.property.SimpleStringProperty
 import javafx.collections.ObservableList
 import javafx.scene.control.TreeItem
@@ -21,7 +22,7 @@ class ProjectStructureView : View() {
       projectContext.projectProperty.addListener { _, _, project ->
          project?.let {
             structureRoot.nameProperty.bind(it.nameProperty)
-            BindingUtil.bindMapValues(structureMaps.items, project.maps)
+            Bindings.bindContent(structureMaps.items, project.maps)
             root.refresh()
          }
       }
diff --git a/editor/src/main/kotlin/com/bartlomiejpluta/base/editor/project/context/DefaultProjectContext.kt b/editor/src/main/kotlin/com/bartlomiejpluta/base/editor/project/context/DefaultProjectContext.kt
index cdad8a77..625b2af6 100644
--- a/editor/src/main/kotlin/com/bartlomiejpluta/base/editor/project/context/DefaultProjectContext.kt
+++ b/editor/src/main/kotlin/com/bartlomiejpluta/base/editor/project/context/DefaultProjectContext.kt
@@ -71,10 +71,10 @@ class DefaultProjectContext : ProjectContext {
 
    override fun importMap(name: String, map: GameMap) {
       project?.let {
-         UID.next(it.maps.keys).let { uid ->
+         UID.next(it.maps.map(Asset::uid)).let { uid ->
             val asset = GameMapAsset(uid, name, map.rows, map.columns)
             map.uid = uid
-            it.maps[uid] = asset
+            it.maps += asset
 
             save()
             File(mapsDirectory, asset.source).outputStream().use { fos -> mapSerializer.serialize(map, fos) }
diff --git a/editor/src/main/kotlin/com/bartlomiejpluta/base/editor/project/model/Project.kt b/editor/src/main/kotlin/com/bartlomiejpluta/base/editor/project/model/Project.kt
index c414702d..4dc4d485 100644
--- a/editor/src/main/kotlin/com/bartlomiejpluta/base/editor/project/model/Project.kt
+++ b/editor/src/main/kotlin/com/bartlomiejpluta/base/editor/project/model/Project.kt
@@ -5,7 +5,6 @@ import javafx.beans.property.SimpleObjectProperty
 import javafx.beans.property.SimpleStringProperty
 import tornadofx.getValue
 import tornadofx.observableListOf
-import tornadofx.observableMapOf
 import tornadofx.setValue
 import java.io.File
 
@@ -16,5 +15,5 @@ class Project {
    val sourceDirectoryProperty = SimpleObjectProperty<File>()
    val sourceDirectory by sourceDirectoryProperty
 
-   val maps = observableMapOf<String, GameMapAsset>()
+   val maps = observableListOf<GameMapAsset>()
 }
diff --git a/editor/src/main/kotlin/com/bartlomiejpluta/base/editor/project/serial/ProtobufProjectDeserializer.kt b/editor/src/main/kotlin/com/bartlomiejpluta/base/editor/project/serial/ProtobufProjectDeserializer.kt
index ee89e638..70c92b80 100644
--- a/editor/src/main/kotlin/com/bartlomiejpluta/base/editor/project/serial/ProtobufProjectDeserializer.kt
+++ b/editor/src/main/kotlin/com/bartlomiejpluta/base/editor/project/serial/ProtobufProjectDeserializer.kt
@@ -4,7 +4,6 @@ import com.bartlomiejpluta.base.editor.map.asset.GameMapAsset
 import com.bartlomiejpluta.base.editor.project.model.Project
 import com.bartlomiejpluta.base.proto.ProjectProto
 import org.springframework.stereotype.Component
-import java.io.File
 import java.io.InputStream
 
 @Component
@@ -14,7 +13,7 @@ class ProtobufProjectDeserializer : ProjectDeserializer {
       val proto = ProjectProto.Project.parseFrom(input)
       val project = Project()
       project.name = proto.name
-      project.maps.putAll(proto.mapsList.map { it.uid to deserializeMap(it) })
+      project.maps.addAll(proto.mapsList.map(this::deserializeMap))
 
       return project
    }
diff --git a/editor/src/main/kotlin/com/bartlomiejpluta/base/editor/project/serial/ProtobufProjectSerializer.kt b/editor/src/main/kotlin/com/bartlomiejpluta/base/editor/project/serial/ProtobufProjectSerializer.kt
index d69e3746..6b34edd3 100644
--- a/editor/src/main/kotlin/com/bartlomiejpluta/base/editor/project/serial/ProtobufProjectSerializer.kt
+++ b/editor/src/main/kotlin/com/bartlomiejpluta/base/editor/project/serial/ProtobufProjectSerializer.kt
@@ -12,7 +12,7 @@ class ProtobufProjectSerializer : ProjectSerializer {
    override fun serialize(item: Project, output: OutputStream) {
       val proto = ProjectProto.Project.newBuilder()
       proto.name = item.name
-      proto.addAllMaps(item.maps.values.map(this::serializeMap))
+      proto.addAllMaps(item.maps.map(this::serializeMap))
       proto.build().writeTo(output)
    }