diff --git a/test/fixtures/transformation/let-scoping/for-break-continue-return/actual.js b/test/fixtures/transformation/let-scoping/for-break-continue-return/actual.js
new file mode 100644
index 0000000000..387d702154
--- /dev/null
+++ b/test/fixtures/transformation/let-scoping/for-break-continue-return/actual.js
@@ -0,0 +1,10 @@
+for (let i in nums) {
+  fns.push(function () { return i; });
+  if (i === 1) {
+    continue;
+  } else if (i === 2) {
+    break;
+  } else if (i === 3) {
+    return i;
+  }
+}
diff --git a/test/fixtures/transformation/let-scoping/for-break-continue-return/expected.js b/test/fixtures/transformation/let-scoping/for-break-continue-return/expected.js
new file mode 100644
index 0000000000..7287b97822
--- /dev/null
+++ b/test/fixtures/transformation/let-scoping/for-break-continue-return/expected.js
@@ -0,0 +1,24 @@
+"use strict";
+
+_loop: for (var i in nums) {
+  var _ret = (function (i) {
+    fns.push(function () {
+      return i;
+    });
+    if (i === 1) {
+      return "continue";
+    } else if (i === 2) {
+      return "break";
+    } else if (i === 3) {
+      return {
+        v: i
+      };
+    }
+  })(i);
+
+  switch (_ret) {
+    case "break": break _loop;
+    case "continue": continue _loop;
+    default: if (typeof _ret === "object") return _ret.v;
+  }
+}
diff --git a/test/fixtures/transformation/let-scoping/for-break/actual.js b/test/fixtures/transformation/let-scoping/for-break/actual.js
new file mode 100644
index 0000000000..ef32b88f58
--- /dev/null
+++ b/test/fixtures/transformation/let-scoping/for-break/actual.js
@@ -0,0 +1,4 @@
+for (let i in nums) {
+  fns.push(function () { return i; });
+  break;
+}
diff --git a/test/fixtures/transformation/let-scoping/for-break/expected.js b/test/fixtures/transformation/let-scoping/for-break/expected.js
new file mode 100644
index 0000000000..96fc3616ef
--- /dev/null
+++ b/test/fixtures/transformation/let-scoping/for-break/expected.js
@@ -0,0 +1,12 @@
+"use strict";
+
+_loop: for (var i in nums) {
+  var _ret = (function (i) {
+    fns.push(function () {
+      return i;
+    });
+    return "break";
+  })(i);
+
+  if (_ret === "break") break _loop;
+}
diff --git a/test/fixtures/transformation/let-scoping/for-continue/actual.js b/test/fixtures/transformation/let-scoping/for-continue/actual.js
new file mode 100644
index 0000000000..4107632d3b
--- /dev/null
+++ b/test/fixtures/transformation/let-scoping/for-continue/actual.js
@@ -0,0 +1,4 @@
+for (let i in nums) {
+  fns.push(function () { return i; });
+  continue;
+}
diff --git a/test/fixtures/transformation/let-scoping/for-continue/expected.js b/test/fixtures/transformation/let-scoping/for-continue/expected.js
new file mode 100644
index 0000000000..658e48536b
--- /dev/null
+++ b/test/fixtures/transformation/let-scoping/for-continue/expected.js
@@ -0,0 +1,12 @@
+"use strict";
+
+_loop: for (var i in nums) {
+  var _ret = (function (i) {
+    fns.push(function () {
+      return i;
+    });
+    return "continue";
+  })(i);
+
+  if (_ret === "continue") continue _loop;
+}
diff --git a/test/fixtures/transformation/let-scoping/for-return-undefined/actual.js b/test/fixtures/transformation/let-scoping/for-return-undefined/actual.js
new file mode 100644
index 0000000000..b7613b4f31
--- /dev/null
+++ b/test/fixtures/transformation/let-scoping/for-return-undefined/actual.js
@@ -0,0 +1,4 @@
+for (let i in nums) {
+  fns.push(function () { return i; });
+  return;
+}
diff --git a/test/fixtures/transformation/let-scoping/for-return-undefined/expected.js b/test/fixtures/transformation/let-scoping/for-return-undefined/expected.js
new file mode 100644
index 0000000000..4937ff43c2
--- /dev/null
+++ b/test/fixtures/transformation/let-scoping/for-return-undefined/expected.js
@@ -0,0 +1,14 @@
+"use strict";
+
+for (var i in nums) {
+  var _ret = (function (i) {
+    fns.push(function () {
+      return i;
+    });
+    return {
+      v: undefined
+    };
+  })(i);
+
+  if (typeof _ret === "object") return _ret.v;
+}
diff --git a/test/fixtures/transformation/let-scoping/for-return/actual.js b/test/fixtures/transformation/let-scoping/for-return/actual.js
new file mode 100644
index 0000000000..8c636baaca
--- /dev/null
+++ b/test/fixtures/transformation/let-scoping/for-return/actual.js
@@ -0,0 +1,4 @@
+for (let i in nums) {
+  fns.push(function () { return i; });
+  return i;
+}
diff --git a/test/fixtures/transformation/let-scoping/for-return/expected.js b/test/fixtures/transformation/let-scoping/for-return/expected.js
new file mode 100644
index 0000000000..d26f70a201
--- /dev/null
+++ b/test/fixtures/transformation/let-scoping/for-return/expected.js
@@ -0,0 +1,14 @@
+"use strict";
+
+for (var i in nums) {
+  var _ret = (function (i) {
+    fns.push(function () {
+      return i;
+    });
+    return {
+      v: i
+    };
+  })(i);
+
+  if (typeof _ret === "object") return _ret.v;
+}
diff --git a/test/fixtures/transformation/let-scoping/function/actual.js b/test/fixtures/transformation/let-scoping/function/actual.js
new file mode 100644
index 0000000000..2b9635ec33
--- /dev/null
+++ b/test/fixtures/transformation/let-scoping/function/actual.js
@@ -0,0 +1,3 @@
+function test() {
+  let foo = "bar";
+}
diff --git a/test/fixtures/transformation/let-scoping/function/expected.js b/test/fixtures/transformation/let-scoping/function/expected.js
new file mode 100644
index 0000000000..dfd0ab9301
--- /dev/null
+++ b/test/fixtures/transformation/let-scoping/function/expected.js
@@ -0,0 +1,5 @@
+"use strict";
+
+function test() {
+  var foo = "bar";
+}
diff --git a/test/fixtures/transformation/let-scoping/program/actual.js b/test/fixtures/transformation/let-scoping/program/actual.js
new file mode 100644
index 0000000000..0de89f04bf
--- /dev/null
+++ b/test/fixtures/transformation/let-scoping/program/actual.js
@@ -0,0 +1 @@
+let test = "foo";
diff --git a/test/fixtures/transformation/let-scoping/program/expected.js b/test/fixtures/transformation/let-scoping/program/expected.js
new file mode 100644
index 0000000000..c8ee0b911a
--- /dev/null
+++ b/test/fixtures/transformation/let-scoping/program/expected.js
@@ -0,0 +1,3 @@
+"use strict";
+
+var test = "foo";
diff --git a/test/fixtures/transformation/let-scoping/closure/actual.js b/test/fixtures/transformation/traceur-let-scoping/closure/actual.js
similarity index 100%
rename from test/fixtures/transformation/let-scoping/closure/actual.js
rename to test/fixtures/transformation/traceur-let-scoping/closure/actual.js
diff --git a/test/fixtures/transformation/let-scoping/closure/expected.js b/test/fixtures/transformation/traceur-let-scoping/closure/expected.js
similarity index 100%
rename from test/fixtures/transformation/let-scoping/closure/expected.js
rename to test/fixtures/transformation/traceur-let-scoping/closure/expected.js
diff --git a/test/fixtures/transformation/let-scoping/deep-nested/exec.js b/test/fixtures/transformation/traceur-let-scoping/deep-nested/exec.js
similarity index 100%
rename from test/fixtures/transformation/let-scoping/deep-nested/exec.js
rename to test/fixtures/transformation/traceur-let-scoping/deep-nested/exec.js
diff --git a/test/fixtures/transformation/let-scoping/for-in-initializers/exec.js b/test/fixtures/transformation/traceur-let-scoping/for-in-initializers/exec.js
similarity index 100%
rename from test/fixtures/transformation/let-scoping/for-in-initializers/exec.js
rename to test/fixtures/transformation/traceur-let-scoping/for-in-initializers/exec.js
diff --git a/test/fixtures/transformation/let-scoping/for-initializers/exec.js b/test/fixtures/transformation/traceur-let-scoping/for-initializers/exec.js
similarity index 100%
rename from test/fixtures/transformation/let-scoping/for-initializers/exec.js
rename to test/fixtures/transformation/traceur-let-scoping/for-initializers/exec.js
diff --git a/test/fixtures/transformation/let-scoping/function-declaration/actual.js b/test/fixtures/transformation/traceur-let-scoping/function-declaration/actual.js
similarity index 100%
rename from test/fixtures/transformation/let-scoping/function-declaration/actual.js
rename to test/fixtures/transformation/traceur-let-scoping/function-declaration/actual.js
diff --git a/test/fixtures/transformation/let-scoping/function-declaration/expected.js b/test/fixtures/transformation/traceur-let-scoping/function-declaration/expected.js
similarity index 100%
rename from test/fixtures/transformation/let-scoping/function-declaration/expected.js
rename to test/fixtures/transformation/traceur-let-scoping/function-declaration/expected.js
diff --git a/test/fixtures/transformation/let-scoping/in-class/exec.js b/test/fixtures/transformation/traceur-let-scoping/in-class/exec.js
similarity index 100%
rename from test/fixtures/transformation/let-scoping/in-class/exec.js
rename to test/fixtures/transformation/traceur-let-scoping/in-class/exec.js
diff --git a/test/fixtures/transformation/let-scoping/in-closure/exec.js b/test/fixtures/transformation/traceur-let-scoping/in-closure/exec.js
similarity index 100%
rename from test/fixtures/transformation/let-scoping/in-closure/exec.js
rename to test/fixtures/transformation/traceur-let-scoping/in-closure/exec.js
diff --git a/test/fixtures/transformation/let-scoping/in-for-break-inner/exec.js b/test/fixtures/transformation/traceur-let-scoping/in-for-break-inner/exec.js
similarity index 100%
rename from test/fixtures/transformation/let-scoping/in-for-break-inner/exec.js
rename to test/fixtures/transformation/traceur-let-scoping/in-for-break-inner/exec.js
diff --git a/test/fixtures/transformation/let-scoping/in-for-break-named/exec.js b/test/fixtures/transformation/traceur-let-scoping/in-for-break-named/exec.js
similarity index 100%
rename from test/fixtures/transformation/let-scoping/in-for-break-named/exec.js
rename to test/fixtures/transformation/traceur-let-scoping/in-for-break-named/exec.js
diff --git a/test/fixtures/transformation/let-scoping/in-for-break/exec.js b/test/fixtures/transformation/traceur-let-scoping/in-for-break/exec.js
similarity index 100%
rename from test/fixtures/transformation/let-scoping/in-for-break/exec.js
rename to test/fixtures/transformation/traceur-let-scoping/in-for-break/exec.js
diff --git a/test/fixtures/transformation/let-scoping/in-for-continue-inner/exec.js b/test/fixtures/transformation/traceur-let-scoping/in-for-continue-inner/exec.js
similarity index 100%
rename from test/fixtures/transformation/let-scoping/in-for-continue-inner/exec.js
rename to test/fixtures/transformation/traceur-let-scoping/in-for-continue-inner/exec.js
diff --git a/test/fixtures/transformation/let-scoping/in-for-continue-named/exec.js b/test/fixtures/transformation/traceur-let-scoping/in-for-continue-named/exec.js
similarity index 100%
rename from test/fixtures/transformation/let-scoping/in-for-continue-named/exec.js
rename to test/fixtures/transformation/traceur-let-scoping/in-for-continue-named/exec.js
diff --git a/test/fixtures/transformation/let-scoping/in-for-continue/exec.js b/test/fixtures/transformation/traceur-let-scoping/in-for-continue/exec.js
similarity index 100%
rename from test/fixtures/transformation/let-scoping/in-for-continue/exec.js
rename to test/fixtures/transformation/traceur-let-scoping/in-for-continue/exec.js
diff --git a/test/fixtures/transformation/let-scoping/in-for/exec.js b/test/fixtures/transformation/traceur-let-scoping/in-for/exec.js
similarity index 100%
rename from test/fixtures/transformation/let-scoping/in-for/exec.js
rename to test/fixtures/transformation/traceur-let-scoping/in-for/exec.js
diff --git a/test/fixtures/transformation/let-scoping/in-properties/exec.js b/test/fixtures/transformation/traceur-let-scoping/in-properties/exec.js
similarity index 100%
rename from test/fixtures/transformation/let-scoping/in-properties/exec.js
rename to test/fixtures/transformation/traceur-let-scoping/in-properties/exec.js
diff --git a/test/fixtures/transformation/let-scoping/initializer-for-1/exec.js b/test/fixtures/transformation/traceur-let-scoping/initializer-for-1/exec.js
similarity index 100%
rename from test/fixtures/transformation/let-scoping/initializer-for-1/exec.js
rename to test/fixtures/transformation/traceur-let-scoping/initializer-for-1/exec.js
diff --git a/test/fixtures/transformation/let-scoping/initializer-for-2/exec.js b/test/fixtures/transformation/traceur-let-scoping/initializer-for-2/exec.js
similarity index 100%
rename from test/fixtures/transformation/let-scoping/initializer-for-2/exec.js
rename to test/fixtures/transformation/traceur-let-scoping/initializer-for-2/exec.js
diff --git a/test/fixtures/transformation/let-scoping/initializer-for-3/exec.js b/test/fixtures/transformation/traceur-let-scoping/initializer-for-3/exec.js
similarity index 100%
rename from test/fixtures/transformation/let-scoping/initializer-for-3/exec.js
rename to test/fixtures/transformation/traceur-let-scoping/initializer-for-3/exec.js
diff --git a/test/fixtures/transformation/let-scoping/initializer-for-in/exec.js b/test/fixtures/transformation/traceur-let-scoping/initializer-for-in/exec.js
similarity index 100%
rename from test/fixtures/transformation/let-scoping/initializer-for-in/exec.js
rename to test/fixtures/transformation/traceur-let-scoping/initializer-for-in/exec.js
diff --git a/test/fixtures/transformation/let-scoping/nested-conflict/exec.js b/test/fixtures/transformation/traceur-let-scoping/nested-conflict/exec.js
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rename from test/fixtures/transformation/let-scoping/nested-conflict/exec.js
rename to test/fixtures/transformation/traceur-let-scoping/nested-conflict/exec.js
diff --git a/test/fixtures/transformation/let-scoping/nested-function-1/exec.js b/test/fixtures/transformation/traceur-let-scoping/nested-function-1/exec.js
similarity index 100%
rename from test/fixtures/transformation/let-scoping/nested-function-1/exec.js
rename to test/fixtures/transformation/traceur-let-scoping/nested-function-1/exec.js
diff --git a/test/fixtures/transformation/let-scoping/nested-function-2/exec.js b/test/fixtures/transformation/traceur-let-scoping/nested-function-2/exec.js
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rename from test/fixtures/transformation/let-scoping/nested-function-2/exec.js
rename to test/fixtures/transformation/traceur-let-scoping/nested-function-2/exec.js
diff --git a/test/fixtures/transformation/let-scoping/nested-function-3/exec.js b/test/fixtures/transformation/traceur-let-scoping/nested-function-3/exec.js
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rename from test/fixtures/transformation/let-scoping/nested-function-3/exec.js
rename to test/fixtures/transformation/traceur-let-scoping/nested-function-3/exec.js
diff --git a/test/fixtures/transformation/let-scoping/nested/exec.js b/test/fixtures/transformation/traceur-let-scoping/nested/exec.js
similarity index 100%
rename from test/fixtures/transformation/let-scoping/nested/exec.js
rename to test/fixtures/transformation/traceur-let-scoping/nested/exec.js
diff --git a/test/fixtures/transformation/let-scoping/no-initializer-global/exec.js b/test/fixtures/transformation/traceur-let-scoping/no-initializer-global/exec.js
similarity index 100%
rename from test/fixtures/transformation/let-scoping/no-initializer-global/exec.js
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rename to test/fixtures/transformation/traceur-let-scoping/no-renaming/actual.js
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rename from test/fixtures/transformation/let-scoping/no-renaming/expected.js
rename to test/fixtures/transformation/traceur-let-scoping/no-renaming/expected.js
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rename to test/fixtures/transformation/traceur-let-scoping/with-for/exec.js
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