diff --git a/zia-lang.org/crate/Cargo.toml b/zia-lang.org/crate/Cargo.toml
index 902c870c..5371f5b1 100644
--- a/zia-lang.org/crate/Cargo.toml
+++ b/zia-lang.org/crate/Cargo.toml
@@ -26,6 +26,19 @@ features = [
   "KeyboardEvent"
 ]
 
+[dev-dependencies.web-sys]
+version = "^0.3.45"
+features = [
+  "Window",
+  "Document",
+  "Element",
+  "Event",
+  "EventTarget",
+  "EventInit",
+  "KeyboardEventInit",
+  "HtmlTextAreaElement"
+]
+
 [profile.release]
 lto = true
 opt-level = 's'
diff --git a/zia-lang.org/crate/src/lib.rs b/zia-lang.org/crate/src/lib.rs
index 31764609..c7ff396d 100644
--- a/zia-lang.org/crate/src/lib.rs
+++ b/zia-lang.org/crate/src/lib.rs
@@ -144,3 +144,72 @@ pub fn run() {
 
     log!("App started.");
 }
+
+#[cfg(test)]
+mod test {
+    extern crate wasm_bindgen_test;
+    use super::run;
+    use seed::{prelude::JsCast, window};
+    use wasm_bindgen_test::*;
+    use web_sys::{HtmlTextAreaElement, KeyboardEvent, KeyboardEventInit};
+
+    wasm_bindgen_test_configure!(run_in_browser);
+
+    fn load_page() {
+        // Need to insert an element with id="app" to mimic the loading screen
+        // defined in ../../entries/index.hbs
+        let document = window().document().unwrap();
+        let section = document.create_element("section").unwrap();
+        section.set_id("app");
+        document.body().unwrap().append_with_node_1(&section).unwrap();
+
+        // Now we can run the WASM part
+        run();
+    }
+
+    #[wasm_bindgen_test]
+    fn keyboard_input_is_displayed_textarea_element() {
+        load_page();
+        let keyboard_event = KeyboardEvent::new_with_keyboard_event_init_dict(
+            "KeyboardEvent",
+            KeyboardEventInit::new().key("x"),
+        )
+        .unwrap();
+        window().document().unwrap().dispatch_event(&keyboard_event).unwrap();
+        let command_input: HtmlTextAreaElement = JsCast::dyn_into(
+            window()
+                .document()
+                .unwrap()
+                .get_element_by_id("command_input")
+                .unwrap(),
+        )
+        .unwrap();
+        assert_eq!(command_input.value(), "x");
+    }
+
+    #[wasm_bindgen_test]
+    fn submitted_command_moves_from_textarea_to_history() {
+        load_page();
+        // TODO: focus textarea
+
+        // TODO: simulate typing text
+
+        // TODO: simulate pressing "Enter"
+
+        // TODO: assert textarea is empty
+
+        // TODO: assert text submitted appears in an element above textarea
+    }
+
+    #[wasm_bindgen_test]
+    fn height_of_textarea_does_not_change_when_typing_one_line() {
+        load_page();
+        // TODO: get the height of the textarea element
+
+        // TODO: simulate typing text
+
+        // TODO: get the height of the textarea element
+
+        // TODO: assert height of textarea element has not changed
+    }
+}
diff --git a/zia-lang.org/crate/src/page/home.rs b/zia-lang.org/crate/src/page/home.rs
index bc1e3511..45068906 100644
--- a/zia-lang.org/crate/src/page/home.rs
+++ b/zia-lang.org/crate/src/page/home.rs
@@ -82,7 +82,7 @@ pub fn view(model: &Model) -> impl IntoNodes<GlobalMsg> {
             C.outline_none,
             C.overflow_hidden
         ],
-        attrs! {At::Type => "text", At::Name => "input"},
+        attrs! {At::Type => "text", At::Name => "input", At::Id => "command_input"},
         style! {St::Resize => "none", St::Height => model.command_input.get().map_or_else(
             // flatten textarea on first render to prevent it being
             // too tall on subsequent renders
diff --git a/zia-lang.org/crate/tests/test.rs b/zia-lang.org/crate/tests/test.rs
deleted file mode 100644
index 3ce8516a..00000000
--- a/zia-lang.org/crate/tests/test.rs
+++ /dev/null
@@ -1,7 +0,0 @@
-extern crate wasm_bindgen_test;
-use wasm_bindgen_test::*;
-
-#[wasm_bindgen_test]
-fn pass() {
-    assert_eq!(1, 1);
-}
diff --git a/zia-lang.org/crate/webdriver.json b/zia-lang.org/crate/webdriver.json
new file mode 100644
index 00000000..76e9221e
--- /dev/null
+++ b/zia-lang.org/crate/webdriver.json
@@ -0,0 +1,9 @@
+{
+    "moz:firefoxOptions": {
+      "prefs": {
+        "media.navigator.streams.fake": true,
+        "media.navigator.permission.disabled": true
+      },
+      "args": []
+    }
+}
\ No newline at end of file
diff --git a/zia/src/concepts/trait.rs b/zia/src/concepts/trait.rs
index 625b0ff6..cfb660ae 100644
--- a/zia/src/concepts/trait.rs
+++ b/zia/src/concepts/trait.rs
@@ -18,8 +18,12 @@ use super::{
 
 pub trait Concept: Sized {
     type Id: Copy + Display + Eq + Hash + Debug;
-    type IdPairIterator<'a>: Iterator<Item = (Self::Id, Self::Id)>;
-    type IdIterator<'a>: Iterator<Item = Self::Id>;
+    type IdPairIterator<'a>: Iterator<Item = (Self::Id, Self::Id)>
+    where
+        Self: 'a;
+    type IdIterator<'a>: Iterator<Item = Self::Id>
+    where
+        Self: 'a;
     fn id(&self) -> Self::Id;
 
     fn maybe_composition(&self) -> Option<MaybeComposition<Self::Id>>;
diff --git a/zia/src/context_snap_shot/concept.rs b/zia/src/context_snap_shot/concept.rs
index 250aff6b..5de49afd 100644
--- a/zia/src/context_snap_shot/concept.rs
+++ b/zia/src/context_snap_shot/concept.rs
@@ -61,9 +61,14 @@ impl<'a, 'b> From<&'a NewDirectConceptDelta<ConceptId, ConceptId>>
 
 impl<'a> ConceptTrait for Mixed<'a> {
     type Id = ConceptId;
-    type IdIterator<'b> = Box<dyn Iterator<Item = Self::Id> + 'b>;
-    type IdPairIterator<'b> =
-        Box<dyn Iterator<Item = (Self::Id, Self::Id)> + 'b>;
+    type IdIterator<'b>
+    where
+        Self: 'b,
+    = Box<dyn Iterator<Item = Self::Id> + 'b>;
+    type IdPairIterator<'b>
+    where
+        Self: 'b,
+    = Box<dyn Iterator<Item = (Self::Id, Self::Id)> + 'b>;
 
     fn id(&self) -> Self::Id {
         match self {
diff --git a/zia/src/snap_shot.rs b/zia/src/snap_shot.rs
index a4640880..f99d3c77 100644
--- a/zia/src/snap_shot.rs
+++ b/zia/src/snap_shot.rs
@@ -37,7 +37,9 @@ where
         + Debug
         + for<'b> From<
             &'b NewDirectConceptDelta<Self::ConceptId, Self::ConceptId>,
-        >;
+        >
+    where
+        Self: 'a;
     fn get_concept(
         &self,
         concept_id: Self::ConceptId,