diff --git a/index.js b/index.js
index b951fd9..3010a47 100644
--- a/index.js
+++ b/index.js
@@ -215,6 +215,12 @@ var extensions = {
         hook(Object.assign({}, config, { extensions: '.jsx' }));
       },
     },
+    {
+      module: 'jiti/lib/jiti-register.mjs',
+      register: function () {
+        process.env.JITI_JSX = true
+      },
+    },
     'sucrase/register/jsx',
   ],
   '.litcoffee': 'coffeescript/register',
@@ -366,6 +372,7 @@ var extensions = {
   '.ts': [
     'ts-node/register',
     'sucrase/register/ts',
+    'jiti/lib/jiti-register.mjs',
     {
       module: '@babel/register',
       register: function (hook, config) {
@@ -425,10 +432,16 @@ var extensions = {
       },
     },
   ],
-  '.cts': ['ts-node/register'],
+  '.cts': ['ts-node/register', 'jiti/lib/jiti-register.mjs'],
   '.tsx': [
     'ts-node/register',
     'sucrase/register/tsx',
+    {
+      module: 'jiti/lib/jiti-register.mjs',
+      register: function () {
+        process.env.JITI_JSX = true
+      },
+    },
     {
       module: '@babel/register',
       register: function (hook, config) {
diff --git a/test/fixtures/cts/1/package.json b/test/fixtures/cts/1/package.json
new file mode 100644
index 0000000..15f2ac2
--- /dev/null
+++ b/test/fixtures/cts/1/package.json
@@ -0,0 +1,5 @@
+{
+  "dependencies": {
+    "jiti": "^2.4.2"
+  }
+}
diff --git a/test/fixtures/cts/1/test.cts b/test/fixtures/cts/1/test.cts
new file mode 100644
index 0000000..3fa0969
--- /dev/null
+++ b/test/fixtures/cts/1/test.cts
@@ -0,0 +1,19 @@
+var test: {
+  data: {
+    trueKey: boolean;
+    falseKey: boolean;
+    subKey: {
+      subProp: number;
+    };
+  };
+} = {
+  data: {
+    trueKey: true,
+    falseKey: false,
+    subKey: {
+      subProp: 1,
+    },
+  },
+};
+
+export default test;
diff --git a/test/fixtures/cts/1/tsconfig.json b/test/fixtures/cts/1/tsconfig.json
new file mode 100644
index 0000000..ca687b6
--- /dev/null
+++ b/test/fixtures/cts/1/tsconfig.json
@@ -0,0 +1,11 @@
+{
+  "compilerOptions": {
+    "target": "es5",
+    "module": "commonjs",
+    "declaration": false,
+    "noImplicitAny": false,
+    "removeComments": true,
+    "sourceMap": true,
+    "outDir": ".tmp"
+  }
+}
diff --git a/test/fixtures/jsx/2/package.json b/test/fixtures/jsx/2/package.json
new file mode 100644
index 0000000..15f2ac2
--- /dev/null
+++ b/test/fixtures/jsx/2/package.json
@@ -0,0 +1,5 @@
+{
+  "dependencies": {
+    "jiti": "^2.4.2"
+  }
+}
diff --git a/test/fixtures/jsx/2/test.jsx b/test/fixtures/jsx/2/test.jsx
new file mode 100644
index 0000000..1e2bee9
--- /dev/null
+++ b/test/fixtures/jsx/2/test.jsx
@@ -0,0 +1,17 @@
+const React = {
+  createElement: function (Component) {
+    return Component();
+  },
+};
+
+// Test harmony arrow functions
+const Component = () => {
+  var trueKey = true;
+  var falseKey = false;
+  var subKey = { subProp: 1 };
+  // Test harmony object short notation
+  return { data: { trueKey, falseKey, subKey } };
+};
+
+// Test JSX syntax
+module.exports = <Component />;
diff --git a/test/fixtures/ts/5/package.json b/test/fixtures/ts/5/package.json
new file mode 100644
index 0000000..15f2ac2
--- /dev/null
+++ b/test/fixtures/ts/5/package.json
@@ -0,0 +1,5 @@
+{
+  "dependencies": {
+    "jiti": "^2.4.2"
+  }
+}
diff --git a/test/fixtures/ts/5/test.ts b/test/fixtures/ts/5/test.ts
new file mode 100644
index 0000000..5044977
--- /dev/null
+++ b/test/fixtures/ts/5/test.ts
@@ -0,0 +1,15 @@
+var test = {
+  data: {
+    trueKey: true,
+    falseKey: false,
+    subKey: {
+      subProp: 1,
+    },
+  },
+};
+
+var main = {
+  default: test,
+};
+
+export = main;
diff --git a/test/fixtures/tsx/5/package.json b/test/fixtures/tsx/5/package.json
new file mode 100644
index 0000000..15f2ac2
--- /dev/null
+++ b/test/fixtures/tsx/5/package.json
@@ -0,0 +1,5 @@
+{
+  "dependencies": {
+    "jiti": "^2.4.2"
+  }
+}
diff --git a/test/fixtures/tsx/5/test.tsx b/test/fixtures/tsx/5/test.tsx
new file mode 100644
index 0000000..d26bcf1
--- /dev/null
+++ b/test/fixtures/tsx/5/test.tsx
@@ -0,0 +1,18 @@
+const React = {
+  createElement(Component: () => any) {
+    return Component();
+  },
+};
+
+// Test harmony arrow functions.
+const Component = () => {
+  var trueKey: boolean = true;
+  var falseKey: boolean = false;
+  var subKey = { subProp: 1 };
+
+  // Test harmony object short notation.
+  return { data: { trueKey, falseKey, subKey } };
+};
+
+// Test TSX syntax.
+export default <Component />;