diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 43d2897..b6ebf3a 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -13,6 +13,8 @@ jobs:
       - uses: actions/checkout@v2
 
       - uses: purescript-contrib/setup-purescript@main
+        with:
+          purescript: "unstable"
 
       - uses: actions/setup-node@v1
         with:
diff --git a/CHANGELOG.md b/CHANGELOG.md
index 6c69383..5ab5c58 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -5,6 +5,7 @@ Notable changes to this project are documented in this file. The format is based
 ## [Unreleased]
 
 Breaking changes:
+- Migrate FFI to ES modules (#51 by @sigma-andex and @JordanMartinez)
 
 New features:
 
diff --git a/bower.json b/bower.json
index a10913d..cb387df 100644
--- a/bower.json
+++ b/bower.json
@@ -17,19 +17,19 @@
     "package.json"
   ],
   "dependencies": {
-    "purescript-control": "^5.0.0",
-    "purescript-either": "^5.0.0",
-    "purescript-gen": "^3.0.0",
-    "purescript-maybe": "^5.0.0",
-    "purescript-newtype": "^4.0.0",
-    "purescript-nonempty": "^6.0.0",
-    "purescript-partial": "^3.0.0",
-    "purescript-prelude": "^5.0.0",
-    "purescript-tuples": "^6.0.0",
-    "purescript-unfoldable": "^5.0.0"
+    "purescript-control": "master",
+    "purescript-either": "master",
+    "purescript-gen": "master",
+    "purescript-maybe": "master",
+    "purescript-newtype": "master",
+    "purescript-nonempty": "master",
+    "purescript-partial": "master",
+    "purescript-prelude": "master",
+    "purescript-tuples": "master",
+    "purescript-unfoldable": "master"
   },
   "devDependencies": {
-    "purescript-assert": "^5.0.0",
-    "purescript-console": "^5.0.0"
+    "purescript-assert": "master",
+    "purescript-console": "master"
   }
 }
diff --git a/package.json b/package.json
index d3602c1..c8e10e0 100644
--- a/package.json
+++ b/package.json
@@ -6,8 +6,8 @@
     "test": "pulp test"
   },
   "devDependencies": {
-    "pulp": "^15.0.0",
-    "purescript-psa": "^0.8.0",
+    "pulp": "16.0.0-0",
+    "purescript-psa": "^0.8.2",
     "rimraf": "^3.0.2"
   }
 }
diff --git a/src/Data/Enum.js b/src/Data/Enum.js
index 126aca0..3b32bf2 100644
--- a/src/Data/Enum.js
+++ b/src/Data/Enum.js
@@ -1,9 +1,7 @@
-"use strict";
-
-exports.toCharCode = function (c) {
+export function toCharCode(c) {
   return c.charCodeAt(0);
-};
+}
 
-exports.fromCharCode = function (c) {
+export function fromCharCode(c) {
   return String.fromCharCode(c);
-};
+}