diff --git a/rescript/bsconfig.json b/rescript/bsconfig.json
index 0b355495..ba1378cf 100644
--- a/rescript/bsconfig.json
+++ b/rescript/bsconfig.json
@@ -6,7 +6,7 @@
     "subdirs" : true
   },
   "package-specs": {
-    "module": "es6",
+    "module": "commonjs",
     "in-source": true
   },
   "suffix": ".bs.js",
diff --git a/rescript/src/Demo.bs.js b/rescript/src/Demo.bs.js
deleted file mode 100644
index 957c5c98..00000000
--- a/rescript/src/Demo.bs.js
+++ /dev/null
@@ -1,9 +0,0 @@
-// Generated by ReScript, PLEASE EDIT WITH CARE
-
-
-console.log("Hello, ReScript");
-
-export {
-  
-}
-/*  Not a pure module */
diff --git a/rescript/src/Demo.res b/rescript/src/Demo.res
deleted file mode 100644
index fcea153b..00000000
--- a/rescript/src/Demo.res
+++ /dev/null
@@ -1,2 +0,0 @@
-
-Js.log("Hello, ReScript")
\ No newline at end of file
diff --git a/rescript/src/Demo_test.bs.js b/rescript/src/Demo_test.bs.js
deleted file mode 100644
index f150754e..00000000
--- a/rescript/src/Demo_test.bs.js
+++ /dev/null
@@ -1,12 +0,0 @@
-// Generated by ReScript, PLEASE EDIT WITH CARE
-
-import * as Jest from "@glennsl/rescript-jest/src/jest.bs.js";
-
-Jest.test("hey", (function (param) {
-        return Jest.Expect.toBe(Jest.Expect.expect(1), 1);
-      }));
-
-export {
-  
-}
-/*  Not a pure module */
diff --git a/rescript/src/Demo_test.res b/rescript/src/Demo_test.res
deleted file mode 100644
index 3fba7fb8..00000000
--- a/rescript/src/Demo_test.res
+++ /dev/null
@@ -1,6 +0,0 @@
-open Jest
-open Expect
-
-test("hey", () => {
-  1->expect->toBe(1)
-})
diff --git a/rescript/src/GildedRose.bs.js b/rescript/src/GildedRose.bs.js
new file mode 100644
index 00000000..f6446add
--- /dev/null
+++ b/rescript/src/GildedRose.bs.js
@@ -0,0 +1,94 @@
+// Generated by ReScript, PLEASE EDIT WITH CARE
+'use strict';
+
+
+function make(name, sellIn, quality) {
+  return {
+          name: name,
+          sellIn: sellIn,
+          quality: quality
+        };
+}
+
+var Item = {
+  make: make
+};
+
+function updateQuality(items) {
+  return items.map(function (item) {
+              var newItem = item;
+              if (item.name !== "Aged Brie" && item.name !== "Backstage passes to a TAFKAL80ETC concert") {
+                if (item.quality > 0 && item.name !== "Sulfuras, Hand of Ragnaros") {
+                  newItem = {
+                    name: item.name,
+                    sellIn: item.sellIn,
+                    quality: item.quality - 1 | 0
+                  };
+                }
+                
+              } else if (item.quality < 50) {
+                newItem = {
+                  name: item.name,
+                  sellIn: item.sellIn,
+                  quality: item.quality + 1 | 0
+                };
+                if (item.name === "Backstage passes to a TAFKAL80ETC concert") {
+                  if (item.sellIn < 11 && item.quality < 50) {
+                    newItem = {
+                      name: item.name,
+                      sellIn: item.sellIn,
+                      quality: item.quality + 1 | 0
+                    };
+                  }
+                  if (item.sellIn < 6 && item.quality < 50) {
+                    newItem = {
+                      name: item.name,
+                      sellIn: item.sellIn,
+                      quality: item.quality + 1 | 0
+                    };
+                  }
+                  
+                }
+                
+              }
+              if (item.name !== "Sulfuras, Hand of Ragnaros") {
+                newItem = {
+                  name: item.name,
+                  sellIn: item.sellIn - 1 | 0,
+                  quality: item.quality
+                };
+              }
+              if (item.sellIn < 0) {
+                if (item.name !== "Aged Brie") {
+                  if (item.name !== "Backstage passes to a TAFKAL80ETC concert") {
+                    if (item.quality > 0 && item.name !== "Sulfuras, Hand of Ragnaros") {
+                      newItem = {
+                        name: item.name,
+                        sellIn: item.sellIn,
+                        quality: item.quality - 1 | 0
+                      };
+                    }
+                    
+                  } else {
+                    newItem = {
+                      name: item.name,
+                      sellIn: item.sellIn,
+                      quality: 0
+                    };
+                  }
+                } else if (item.quality < 50) {
+                  newItem = {
+                    name: item.name,
+                    sellIn: item.sellIn,
+                    quality: item.quality + 1 | 0
+                  };
+                }
+                
+              }
+              return newItem;
+            });
+}
+
+exports.Item = Item;
+exports.updateQuality = updateQuality;
+/* No side effect */
diff --git a/rescript/src/GildedRose.res b/rescript/src/GildedRose.res
new file mode 100644
index 00000000..4af4758d
--- /dev/null
+++ b/rescript/src/GildedRose.res
@@ -0,0 +1,65 @@
+module Item = {
+  type t = {
+    name: string,
+    sellIn: int,
+    quality: int,
+  }
+
+  let make = (~name, ~sellIn, ~quality): t => {
+    name,
+    sellIn,
+    quality,
+  }
+}
+
+let updateQuality = (items: array<Item.t>) => {
+  items->Js.Array2.map(item => {
+    let newItem = ref(item)
+
+    if item.name != "Aged Brie" && item.name != "Backstage passes to a TAFKAL80ETC concert" {
+      if item.quality > 0 {
+        if item.name != "Sulfuras, Hand of Ragnaros" {
+          newItem := {...item, quality: item.quality - 1}
+        }
+      }
+    } else if item.quality < 50 {
+      newItem := {...item, quality: item.quality + 1}
+
+      if item.name == "Backstage passes to a TAFKAL80ETC concert" {
+        if item.sellIn < 11 {
+          if item.quality < 50 {
+            newItem := {...item, quality: item.quality + 1}
+          }
+        }
+
+        if item.sellIn < 6 {
+          if item.quality < 50 {
+            newItem := {...item, quality: item.quality + 1}
+          }
+        }
+      }
+    }
+
+    if item.name != "Sulfuras, Hand of Ragnaros" {
+      newItem := {...item, sellIn: item.sellIn - 1}
+    }
+
+    if item.sellIn < 0 {
+      if item.name != "Aged Brie" {
+        if item.name != "Backstage passes to a TAFKAL80ETC concert" {
+          if item.quality > 0 {
+            if item.name != "Sulfuras, Hand of Ragnaros" {
+              newItem := {...item, quality: item.quality - 1}
+            }
+          }
+        } else {
+          newItem := {...item, quality: 0}
+        }
+      } else if item.quality < 50 {
+        newItem := {...item, quality: item.quality + 1}
+      }
+    }
+
+    newItem.contents
+  })
+}
diff --git a/rescript/src/GildedRose_test.bs.js b/rescript/src/GildedRose_test.bs.js
new file mode 100644
index 00000000..522b02ac
--- /dev/null
+++ b/rescript/src/GildedRose_test.bs.js
@@ -0,0 +1,20 @@
+// Generated by ReScript, PLEASE EDIT WITH CARE
+'use strict';
+
+var Jest = require("@glennsl/rescript-jest/src/jest.bs.js");
+var Caml_array = require("rescript/lib/js/caml_array.js");
+var GildedRose = require("./GildedRose.bs.js");
+
+Jest.describe("Gilded Rose", (function (param) {
+        Jest.test("should foo", (function (param) {
+                var items = [{
+                    name: "foo",
+                    sellIn: 0,
+                    quality: 0
+                  }];
+                var updatedItems = GildedRose.updateQuality(items);
+                return Jest.Expect.toBe(Jest.Expect.expect(Caml_array.get(updatedItems, 0).name), "fixme");
+              }));
+      }));
+
+/*  Not a pure module */
diff --git a/rescript/src/GildedRose_test.res b/rescript/src/GildedRose_test.res
new file mode 100644
index 00000000..6cf7c024
--- /dev/null
+++ b/rescript/src/GildedRose_test.res
@@ -0,0 +1,11 @@
+open Jest
+open Expect
+open GildedRose
+
+describe("Gilded Rose", () => {
+  test("should foo", () => {
+    let items: array<Item.t> = [{name: "foo", sellIn: 0, quality: 0}]
+    let updatedItems = updateQuality(items)
+    expect(updatedItems[0].name)->toBe("fixme")
+  })
+})
diff --git a/rescript/src/TextTest.bs.js b/rescript/src/TextTest.bs.js
new file mode 100644
index 00000000..1f393649
--- /dev/null
+++ b/rescript/src/TextTest.bs.js
@@ -0,0 +1,42 @@
+// Generated by ReScript, PLEASE EDIT WITH CARE
+'use strict';
+
+var Process = require("process");
+var Belt_Array = require("rescript/lib/js/belt_Array.js");
+var Caml_array = require("rescript/lib/js/caml_array.js");
+var GildedRose = require("./GildedRose.bs.js");
+var Belt_Option = require("rescript/lib/js/belt_Option.js");
+var Caml_format = require("rescript/lib/js/caml_format.js");
+
+console.log("OMGHAI!");
+
+var items = {
+  contents: [
+    GildedRose.Item.make("+5 Dexterity Vest", 10, 20),
+    GildedRose.Item.make("Aged Brie", 2, 0),
+    GildedRose.Item.make("Elixir of the Mongoose", 5, 7),
+    GildedRose.Item.make("Sulfuras, Hand of Ragnaros", 0, 80),
+    GildedRose.Item.make("Sulfuras, Hand of Ragnaros", -1, 80),
+    GildedRose.Item.make("Backstage passes to a TAFKAL80ETC concert", 15, 20),
+    GildedRose.Item.make("Backstage passes to a TAFKAL80ETC concert", 10, 49),
+    GildedRose.Item.make("Backstage passes to a TAFKAL80ETC concert", 5, 49),
+    GildedRose.Item.make("Conjured Mana Cake", 3, 6)
+  ]
+};
+
+var days = Belt_Option.mapWithDefault(Belt_Array.get(Process.argv, 2), 31, Caml_format.int_of_string);
+
+for(var i = 0; i <= days; ++i){
+  console.log("-------- day " + String(i) + " --------");
+  console.log("name, sellIn, quality");
+  for(var j = 0 ,j_finish = items.contents.length; j < j_finish; ++j){
+    var item = Caml_array.get(items.contents, j);
+    console.log(item.name + ", " + String(item.sellIn) + ", " + String(item.quality));
+  }
+  console.log("");
+  items.contents = GildedRose.updateQuality(items.contents);
+}
+
+exports.items = items;
+exports.days = days;
+/*  Not a pure module */
diff --git a/rescript/src/TextTest.res b/rescript/src/TextTest.res
new file mode 100644
index 00000000..b8f208cf
--- /dev/null
+++ b/rescript/src/TextTest.res
@@ -0,0 +1,28 @@
+open GildedRose
+
+Js.log("OMGHAI!")
+
+let items: ref<array<Item.t>> = ref([
+  Item.make(~name="+5 Dexterity Vest", ~sellIn=10, ~quality=20),
+  Item.make(~name="Aged Brie", ~sellIn=2, ~quality=0),
+  Item.make(~name="Elixir of the Mongoose", ~sellIn=5, ~quality=7),
+  Item.make(~name="Sulfuras, Hand of Ragnaros", ~sellIn=0, ~quality=80),
+  Item.make(~name="Sulfuras, Hand of Ragnaros", ~sellIn=-1, ~quality=80),
+  Item.make(~name="Backstage passes to a TAFKAL80ETC concert", ~sellIn=15, ~quality=20),
+  Item.make(~name="Backstage passes to a TAFKAL80ETC concert", ~sellIn=10, ~quality=49),
+  Item.make(~name="Backstage passes to a TAFKAL80ETC concert", ~sellIn=5, ~quality=49),
+  Item.make(~name="Conjured Mana Cake", ~sellIn=3, ~quality=6),
+])
+
+let days = Node.Process.argv->Belt.Array.get(2)->Belt.Option.mapWithDefault(31, int_of_string)
+
+for i in 0 to days {
+  Js.log("-------- day " ++ string_of_int(i) ++ " --------")
+  Js.log("name, sellIn, quality")
+  for j in 0 to Js.Array2.length(items.contents) - 1 {
+    let item = items.contents[j]
+    Js.log(item.name ++ ", " ++ string_of_int(item.sellIn) ++ ", " ++ string_of_int(item.quality))
+  }
+  Js.log("")
+  items := updateQuality(items.contents)
+}