diff --git a/test/features.test.js b/test/features.test.js
new file mode 100644
index 0000000..2fc5fe6
--- /dev/null
+++ b/test/features.test.js
@@ -0,0 +1,35 @@
+import assert from "assert";
+import Core from "../lib";
+
+describe("features", function () {
+  let core;
+  it("a feature's schema is loaded", async function () {
+    const cards = {
+      schema: `
+      create table if not exists cards(
+        id INTEGER PRIMARY KEY
+      );`,
+    };
+    core = await Core.init({ features: [cards] }, { internals: true });
+
+    const tables = core._internals.listTables;
+    assert.ok(tables.includes("cards"));
+  });
+  it("a feature's handlers can be declared", async function () {
+    const cards = {
+      schema: `
+      create table if not exists cards(
+        id INTEGER PRIMARY KEY
+      );`,
+      handlers: {
+        myHandler: (handlerArg) => {
+          assert.ok(handlerArg);
+          return "myHandler";
+        },
+      },
+    };
+    core = await Core.init({ features: { cards } });
+    const result = core.cards.myhandler();
+    assert.strictEqual(result, "myHandler");
+  });
+});
diff --git a/test/features.test.ts b/test/features.test.ts
deleted file mode 100644
index 69cb437..0000000
--- a/test/features.test.ts
+++ /dev/null
@@ -1,18 +0,0 @@
-import * as assert from "assert";
-import Core, { App } from "../lib";
-
-describe("init", function() {
-  let core: App;
-  it("each feature context is loaded", async function(){
-    const cards  = {
-      schema: `
-      create table if not exists cards(
-        id INTEGER PRIMARY KEY
-      );`
-    }
-    core = await Core.init({features: [cards]}, {internals: true});
-
-   const tables =  core._internals.listTables
-   assert.ok(tables.includes('cards'))
-  })
-});
diff --git a/test/helpers.ts b/test/helpers.js
similarity index 100%
rename from test/helpers.ts
rename to test/helpers.js
diff --git a/test/init.test.js b/test/init.test.js
new file mode 100644
index 0000000..0c8e006
--- /dev/null
+++ b/test/init.test.js
@@ -0,0 +1,17 @@
+import * as assert from "assert";
+import Core, { App } from "../lib";
+
+describe("init", function () {
+  let core: App;
+  it("before initialization, no other keys are set", async function () {
+    assert.ok("init" in Core);
+    assert.rejects("state" in Core);
+    core = await Core.init();
+    assert.ok("state" in core);
+    assert.ok("init" in core);
+  });
+  it("adds access to _internals when internals option is true", async function () {
+    core = await Core.init({}, { internals: true });
+    assert.ok("_internals" in core);
+  });
+});
diff --git a/test/init.test.ts b/test/init.test.ts
deleted file mode 100644
index dec1868..0000000
--- a/test/init.test.ts
+++ /dev/null
@@ -1,17 +0,0 @@
-import * as assert from "assert";
-import Core, { App } from "../lib";
-
-describe("init", function() {
-  let core: App;
-  it("core contains critical keys", async function() {
-    core = await Core.init();
-    assert.ok('init' in core);
-    assert.ok('state' in core);
-    assert.ok('pushState' in core);
-    assert.ok('setState' in core);
-  });
-  it("core adds an _internals key when internals option is true", async function() {
-    core = await Core.init({}, {internals: true});
-    assert.ok('_internals' in core);
-  });
-});
diff --git a/test/pushState.test.ts b/test/pushState.test.ts
deleted file mode 100644
index 23bd99e..0000000
--- a/test/pushState.test.ts
+++ /dev/null
@@ -1,23 +0,0 @@
-import * as assert from "assert";
-import Core, { App } from "../lib";
-
-describe("state", function() {
-  let core: App;
-  it("calls pushState on init", async function() {
-    var called = false;
-    core = await Core.init({
-      refreshCards: () => [],
-      pushState: () => (called = true)
-    });
-    assert.equal(called, true);
-  });
-  it("calls pushState on handler call", async function() {
-    let callCount = 0;
-    core = await Core.init({
-      refreshCards: () => [],
-      pushState: () => (callCount += 1)
-    });
-    core.setState.resetViewer();
-    assert.equal(callCount, 2);
-  });
-});
diff --git a/test/state.test.js b/test/state.test.js
new file mode 100644
index 0000000..8ccc294
--- /dev/null
+++ b/test/state.test.js
@@ -0,0 +1,30 @@
+import assert from "assert";
+import Core from "../lib";
+
+describe("state", function () {
+  let core;
+  it("core.state is empty object by default", async function () {
+    core = await Core.init();
+    assert.strictEqual(core.state, {});
+  });
+  it("core.state returns declared state columns", async function () {
+    core = await Core.init({
+      stateColumns: ["my_column integer"],
+    });
+    assert.notStrictEqual(core.state, { my_column: null });
+  });
+
+  it("core.state calls buildState", async function () {
+    let calls = 0;
+    core = await Core.init({
+      buildState: (partial, core) => {
+        calls++;
+        assert.strictEqual(partial, {});
+        assert.ok(core); //gets a truthy value
+        return { my_state: true };
+      },
+    });
+    assert.strictEqual(calls, 1);
+    assert.strictEqual(core.state, { my_column: null });
+  });
+});
diff --git a/test/state.test.ts b/test/state.test.ts
deleted file mode 100644
index af22119..0000000
--- a/test/state.test.ts
+++ /dev/null
@@ -1,13 +0,0 @@
-import * as assert from "assert";
-import Core, { App } from "../lib";
-
-describe("state", function() {
-  let core: App;
-  it("core.state returns current client state", async function() {
-    core = await Core.init({ refreshCards: () => [] });
-    assert.notStrictEqual(core.state, {
-      viewingId: null,
-      viewing: null
-    });
-  });
-});