diff --git a/demo/gdml/src/jsMain/kotlin/space/kscience/visionforge/gdml/demo/GDMLAppComponent.kt b/demo/gdml/src/jsMain/kotlin/space/kscience/visionforge/gdml/demo/GDMLAppComponent.kt
index 4f6560b6..0c52257d 100644
--- a/demo/gdml/src/jsMain/kotlin/space/kscience/visionforge/gdml/demo/GDMLAppComponent.kt
+++ b/demo/gdml/src/jsMain/kotlin/space/kscience/visionforge/gdml/demo/GDMLAppComponent.kt
@@ -1,6 +1,9 @@
 package space.kscience.visionforge.gdml.demo
 
 import kotlinx.browser.window
+import kotlinx.coroutines.CompletableDeferred
+import kotlinx.coroutines.Deferred
+import org.w3c.files.File
 import org.w3c.files.FileReader
 import org.w3c.files.get
 import react.*
@@ -27,32 +30,43 @@ external interface GDMLAppProps : RProps {
 @JsExport
 val GDMLApp = functionalComponent<GDMLAppProps>("GDMLApp") { props ->
     val visionManager = useMemo(props.context) { props.context.fetch(Solids).visionManager }
-    var vision: Solid? by useState { props.vision?.apply { root(visionManager) } }
+    var deferredVision: Deferred<Solid?> by useState {
+        CompletableDeferred(props.vision)
+    }
 
-    fun loadData(name: String, data: String) {
-        val parsedVision = when {
-            name.endsWith(".gdml") || name.endsWith(".xml") -> {
-                val gdml = Gdml.decodeFromString(data)
-                gdml.toVision().apply {
-                    root(visionManager)
-                    console.info("Marking layers for file $name")
-                    markLayers()
+    fun readFileAsync(file: File): Deferred<Solid?> {
+        val deferred = CompletableDeferred<Solid?>()
+        FileReader().apply {
+            onload = {
+                val data = result as String
+                val name = file.name
+                val parsedVision = when {
+                    name.endsWith(".gdml") || name.endsWith(".xml") -> {
+                        val gdml = Gdml.decodeFromString(data)
+                        gdml.toVision().apply {
+                            root(visionManager)
+                            console.info("Marking layers for file $name")
+                            markLayers()
+                        }
+                    }
+                    name.endsWith(".json") -> visionManager.decodeFromString(data)
+                    else -> {
+                        window.alert("File extension is not recognized: $name")
+                        error("File extension is not recognized: $name")
+                    }
                 }
+                deferred.complete(parsedVision as? Solid ?: error("Parsed vision is not a solid"))
             }
-            name.endsWith(".json") -> visionManager.decodeFromString(data)
-            else -> {
-                window.alert("File extension is not recognized: $name")
-                error("File extension is not recognized: $name")
-            }
+            readAsText(file)
         }
 
-        vision = parsedVision as? Solid ?: error("Parsed vision is not a solid")
+        return deferred
     }
 
     child(ThreeCanvasWithControls) {
         attrs {
             this.context = props.context
-            this.solid = vision
+            this.builderOfSolid = deferredVision
             this.selected = props.selected
             tab("Load") {
                 h2 {
@@ -61,13 +75,7 @@ val GDMLApp = functionalComponent<GDMLAppProps>("GDMLApp") { props ->
                 fileDrop("(drag file here)") { files ->
                     val file = files?.get(0)
                     if (file != null) {
-                        FileReader().apply {
-                            onload = {
-                                val string = result as String
-                                loadData(file.name, string)
-                            }
-                            readAsText(file)
-                        }
+                        deferredVision = readFileAsync(file)
                     }
                 }
             }
diff --git a/demo/js-playground/src/main/kotlin/JsPlaygroundApp.kt b/demo/js-playground/src/main/kotlin/JsPlaygroundApp.kt
index a54e48c9..55407e4f 100644
--- a/demo/js-playground/src/main/kotlin/JsPlaygroundApp.kt
+++ b/demo/js-playground/src/main/kotlin/JsPlaygroundApp.kt
@@ -1,5 +1,4 @@
 import kotlinx.browser.document
-import kotlinx.coroutines.GlobalScope
 import kotlinx.coroutines.delay
 import kotlinx.coroutines.isActive
 import kotlinx.coroutines.launch
@@ -17,6 +16,7 @@ import space.kscience.visionforge.VisionClient
 import space.kscience.visionforge.plotly.PlotlyPlugin
 import space.kscience.visionforge.ring.ThreeCanvasWithControls
 import space.kscience.visionforge.ring.ThreeWithControlsPlugin
+import space.kscience.visionforge.ring.solid
 import space.kscience.visionforge.solid.*
 import space.kscience.visionforge.startApplication
 import styled.css
@@ -38,51 +38,6 @@ private class JsPlaygroundApp : Application {
 
         val bouncingSphereTrace = Trace()
 
-        val bouncingSphere = SolidGroup {
-            sphere(5.0, "ball") {
-                detail = 16
-                color("red")
-                val h = 100.0
-                y = h
-                GlobalScope.launch {
-                    val g = 10.0
-                    val dt = 0.1
-                    var time = 0.0
-                    var velocity = 0.0
-                    while (isActive) {
-                        delay(20)
-                        time += dt
-                        velocity -= g * dt
-                        y = y.toDouble() + velocity * dt
-                        bouncingSphereTrace.appendXY(time, y)
-                        if (y.toDouble() <= 2.5) {
-                            //conservation of energy
-                            velocity = sqrt(2 * g * h)
-                        }
-                    }
-                }
-            }
-
-            box(200, 5, 200, name = "floor") {
-                y = -2.5
-            }
-        }
-        val random = Random(112233)
-
-        val visionOfSpheres = SolidGroup {
-            repeat(100) {
-                sphere(5, name = "sphere[$it]") {
-                    x = random.nextDouble(-300.0, 300.0)
-                    y = random.nextDouble(-300.0, 300.0)
-                    z = random.nextDouble(-300.0, 300.0)
-                    material {
-                        color(random.nextInt())
-                    }
-                    detail = 16
-                }
-            }
-        }
-
         render(element) {
             styledDiv {
                 css {
@@ -94,18 +49,46 @@ private class JsPlaygroundApp : Application {
                 SmartTabs("gravity") {
                     Tab("gravity") {
                         styledDiv {
-                            css{
+                            css {
                                 height = 50.vh
                             }
                             child(ThreeCanvasWithControls) {
                                 attrs {
                                     context = playgroundContext
-                                    solid = bouncingSphere
+                                    solid {
+                                        sphere(5.0, "ball") {
+                                            detail = 16
+                                            color("red")
+                                            val h = 100.0
+                                            y = h
+                                            launch {
+                                                val g = 10.0
+                                                val dt = 0.1
+                                                var time = 0.0
+                                                var velocity = 0.0
+                                                while (isActive) {
+                                                    delay(20)
+                                                    time += dt
+                                                    velocity -= g * dt
+                                                    y = y.toDouble() + velocity * dt
+                                                    bouncingSphereTrace.appendXY(time, y)
+                                                    if (y.toDouble() <= 2.5) {
+                                                        //conservation of energy
+                                                        velocity = sqrt(2 * g * h)
+                                                    }
+                                                }
+                                            }
+                                        }
+
+                                        box(200, 5, 200, name = "floor") {
+                                            y = -2.5
+                                        }
+                                    }
                                 }
                             }
                         }
                         styledDiv {
-                            css{
+                            css {
                                 height = 40.vh
                             }
 
@@ -129,10 +112,28 @@ private class JsPlaygroundApp : Application {
 //                        }
 //                    }
                     Tab("spheres") {
-                        child(ThreeCanvasWithControls) {
-                            attrs {
-                                context = playgroundContext
-                                solid = visionOfSpheres
+                        styledDiv {
+                            css {
+                                height = 90.vh
+                            }
+                            child(ThreeCanvasWithControls) {
+                                val random = Random(112233)
+                                attrs {
+                                    context = playgroundContext
+                                    solid {
+                                        repeat(100) {
+                                            sphere(5, name = "sphere[$it]") {
+                                                x = random.nextDouble(-300.0, 300.0)
+                                                y = random.nextDouble(-300.0, 300.0)
+                                                z = random.nextDouble(-300.0, 300.0)
+                                                material {
+                                                    color(random.nextInt())
+                                                }
+                                                detail = 16
+                                            }
+                                        }
+                                    }
+                                }
                             }
                         }
                     }
diff --git a/ui/ring/src/main/kotlin/ringui/Loader.kt b/ui/ring/src/main/kotlin/ringui/Loader.kt
new file mode 100644
index 00000000..c58d51c1
--- /dev/null
+++ b/ui/ring/src/main/kotlin/ringui/Loader.kt
@@ -0,0 +1,19 @@
+@file:JsModule("@jetbrains/ring-ui/components/loader/loader")
+@file:JsNonModule
+
+package ringui
+
+import react.ComponentClass
+import react.dom.WithClassName
+
+// https://github.com/JetBrains/ring-ui/blob/master/components/loader/loader.js
+public external interface LoaderProps : WithClassName {
+    public var size: Number
+    public var colors: Array<String>
+    public var message: String
+    public var stop: Boolean
+    public var deterministic: Boolean
+}
+
+@JsName("default")
+public external val Loader: ComponentClass<LoaderProps>
\ No newline at end of file
diff --git a/ui/ring/src/main/kotlin/ringui/LoaderScreen.kt b/ui/ring/src/main/kotlin/ringui/LoaderScreen.kt
new file mode 100644
index 00000000..8d0bf578
--- /dev/null
+++ b/ui/ring/src/main/kotlin/ringui/LoaderScreen.kt
@@ -0,0 +1,16 @@
+@file:JsModule("@jetbrains/ring-ui/components/loader-screen/loader-screen")
+@file:JsNonModule
+
+package ringui
+
+import react.ComponentClass
+import react.dom.WithClassName
+
+// https://github.com/JetBrains/ring-ui/blob/master/components/loader-screen/loader-screen.js
+public external interface LoaderScreenProps : WithClassName {
+    public var containerClassName: String
+    public var message: String
+}
+
+@JsName("default")
+public external val LoaderScreen: ComponentClass<LoaderScreenProps>
\ No newline at end of file
diff --git a/ui/ring/src/main/kotlin/space.kscience.visionforge.ring/ThreeViewWithControls.kt b/ui/ring/src/main/kotlin/space.kscience.visionforge.ring/ThreeViewWithControls.kt
index a14d23ca..06cffdd0 100644
--- a/ui/ring/src/main/kotlin/space.kscience.visionforge.ring/ThreeViewWithControls.kt
+++ b/ui/ring/src/main/kotlin/space.kscience.visionforge.ring/ThreeViewWithControls.kt
@@ -1,18 +1,19 @@
 package space.kscience.visionforge.ring
 
+import kotlinx.coroutines.Deferred
+import kotlinx.coroutines.async
+import kotlinx.coroutines.launch
 import kotlinx.css.*
 import react.*
 import react.dom.div
 import react.dom.span
-import ringui.Island
-import ringui.IslandContent
-import ringui.IslandHeader
-import ringui.Link
+import ringui.*
 import space.kscience.dataforge.context.Context
 import space.kscience.dataforge.names.Name
 import space.kscience.dataforge.names.NameToken
 import space.kscience.dataforge.names.isEmpty
 import space.kscience.dataforge.names.length
+import space.kscience.visionforge.Vision
 import space.kscience.visionforge.VisionGroup
 import space.kscience.visionforge.computeProperties
 import space.kscience.visionforge.react.ThreeCanvasComponent
@@ -20,17 +21,24 @@ import space.kscience.visionforge.react.flexColumn
 import space.kscience.visionforge.react.flexRow
 import space.kscience.visionforge.react.propertyEditor
 import space.kscience.visionforge.solid.Solid
+import space.kscience.visionforge.solid.SolidGroup
 import space.kscience.visionforge.solid.specifications.Canvas3DOptions
 import styled.css
 import styled.styledDiv
 
 public external interface ThreeCanvasWithControlsProps : RProps {
     public var context: Context
-    public var solid: Solid?
+    public var builderOfSolid: Deferred<Solid?>
     public var selected: Name?
     public var additionalTabs: Map<String, RBuilder.() -> Unit>?
 }
 
+public fun ThreeCanvasWithControlsProps.solid(block: SolidGroup.() -> Unit) {
+    builderOfSolid = context.async {
+        SolidGroup(block)
+    }
+}
+
 public fun ThreeCanvasWithControlsProps.tab(title: String, block: RBuilder.() -> Unit) {
     additionalTabs = (additionalTabs ?: emptyMap()) + (title to block)
 }
@@ -72,6 +80,13 @@ public fun RBuilder.nameCrumbs(name: Name?, link: (Name) -> Unit): ReactElement
 public val ThreeCanvasWithControls: FunctionComponent<ThreeCanvasWithControlsProps> =
     functionalComponent("ThreeViewWithControls") { props ->
         var selected by useState { props.selected }
+        var solid: Solid? by useState(null)
+
+        useEffect {
+            props.context.launch {
+                solid = props.builderOfSolid.await()
+            }
+        }
 
         val onSelect: (Name?) -> Unit = {
             selected = it
@@ -83,15 +98,16 @@ public val ThreeCanvasWithControls: FunctionComponent<ThreeCanvasWithControlsPro
             }
         }
 
-        val selectedVision = useMemo(selected) {
+        val selectedVision: Vision? = useMemo(props.builderOfSolid, selected) {
             selected?.let {
                 when {
-                    it.isEmpty() -> props.solid
-                    else -> (props.solid as? VisionGroup)?.get(it)
+                    it.isEmpty() -> solid
+                    else -> (solid as? VisionGroup)?.get(it)
                 }
             }
         }
 
+
         flexRow {
             css {
                 height = 100.pct
@@ -108,12 +124,20 @@ public val ThreeCanvasWithControls: FunctionComponent<ThreeCanvasWithControlsPro
                     position = Position.relative
                 }
 
-                child(ThreeCanvasComponent) {
-                    attrs {
-                        this.context = props.context
-                        this.solid = props.solid
-                        this.selected = selected
-                        this.options = options
+                if (solid == null) {
+                    LoaderScreen {
+                        attrs {
+                            message = "Loading Three vision"
+                        }
+                    }
+                } else {
+                    child(ThreeCanvasComponent) {
+                        attrs {
+                            this.context = props.context
+                            this.solid = solid
+                            this.selected = selected
+                            this.options = options
+                        }
                     }
                 }
 
@@ -150,7 +174,8 @@ public val ThreeCanvasWithControls: FunctionComponent<ThreeCanvasWithControlsPro
                     minWidth = 400.px
                     flex(1.0, 10.0, FlexBasis("300px"))
                 }
-                ringThreeControls(options, props.solid, selected, onSelect, additionalTabs = props.additionalTabs)
+                ringThreeControls(options, solid, selected, onSelect, additionalTabs = props.additionalTabs)
             }
         }
     }
+
diff --git a/ui/ring/src/main/kotlin/space.kscience.visionforge.ring/ThreeWithControlsPlugin.kt b/ui/ring/src/main/kotlin/space.kscience.visionforge.ring/ThreeWithControlsPlugin.kt
index c4cf64a7..c01b5ae1 100644
--- a/ui/ring/src/main/kotlin/space.kscience.visionforge.ring/ThreeWithControlsPlugin.kt
+++ b/ui/ring/src/main/kotlin/space.kscience.visionforge.ring/ThreeWithControlsPlugin.kt
@@ -1,5 +1,6 @@
 package space.kscience.visionforge.ring
 
+import kotlinx.coroutines.async
 import org.w3c.dom.Element
 import react.child
 import space.kscience.dataforge.context.AbstractPlugin
@@ -28,7 +29,7 @@ public class ThreeWithControlsPlugin : AbstractPlugin(), ElementVisionRenderer {
             child(ThreeCanvasWithControls) {
                 attrs {
                     this.context = this@ThreeWithControlsPlugin.context
-                    this.solid = vision as? Solid
+                    this.builderOfSolid = context.async { vision as Solid}
                 }
             }
         }
diff --git a/visionforge-core/src/jsMain/kotlin/space/kscience/visionforge/Application.kt b/visionforge-core/src/jsMain/kotlin/space/kscience/visionforge/Application.kt
index f9ba8e46..5e1e2470 100644
--- a/visionforge-core/src/jsMain/kotlin/space/kscience/visionforge/Application.kt
+++ b/visionforge-core/src/jsMain/kotlin/space/kscience/visionforge/Application.kt
@@ -1,7 +1,10 @@
 package space.kscience.visionforge
 
 import kotlinx.browser.document
+import kotlinx.coroutines.CoroutineScope
 import kotlinx.dom.hasClass
+import kotlin.coroutines.CoroutineContext
+import kotlin.coroutines.EmptyCoroutineContext
 
 
 public external val module: Module
@@ -25,7 +28,10 @@ public external interface Module {
  *
  * Base interface for applications supporting Hot Module Replacement (HMR).
  */
-public interface Application {
+public interface Application: CoroutineScope {
+
+    override val coroutineContext: CoroutineContext get() = EmptyCoroutineContext
+
     /**
      * Starting point for an application.
      * @param state Initial state between Hot Module Replacement (HMR).