diff --git a/.travis.yml b/.travis.yml
index 2e30c22..a3c2cac 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -1,17 +1,22 @@
+
 language: node_js
-dist: trusty
 sudo: required
-node_js: stable
+dist: trusty
+node_js: 8
+env:
+  - PATH=$HOME/purescript:$PATH
 install:
+  - TAG=$(wget -q -O - https://github.com/purescript/purescript/releases/latest --server-response --max-redirect 0 2>&1 | sed -n -e 's/.*Location:.*tag\///p')
+  - wget -O $HOME/purescript.tar.gz https://github.com/purescript/purescript/releases/download/$TAG/linux64.tar.gz
+  - tar -xvf $HOME/purescript.tar.gz -C $HOME/
+  - chmod a+x $HOME/purescript
   - npm install -g bower
   - npm install
 script:
-  - bower install --production
-  - npm run -s build
   - bower install
-  - npm -s test
+  - pulp test
 after_success:
 - >-
   test $TRAVIS_TAG &&
   echo $GITHUB_TOKEN | pulp login &&
-  echo y | pulp publish --no-push
+  echo y | pulp publish --no-push
\ No newline at end of file
diff --git a/bower.json b/bower.json
index 638a0d7..2fe4531 100644
--- a/bower.json
+++ b/bower.json
@@ -22,12 +22,12 @@
   },
   "license": "MIT",
   "dependencies": {
-    "purescript-argonaut-core": "#compiler/0.12",
-    "purescript-integers": "#compiler/0.12",
-    "purescript-maybe": "#compiler/0.12",
-    "purescript-foreign-object": "#compiler/0.12"
+    "purescript-argonaut-core": "^4.0.0",
+    "purescript-integers": "^4.0.0",
+    "purescript-maybe": "^4.0.0",
+    "purescript-foreign-object": "^1.0.0"
   },
   "devDependencies": {
     "purescript-strongcheck": "#compiler/0.12"
   }
-}
+}
\ No newline at end of file
diff --git a/package.json b/package.json
index 7f64eea..824132e 100644
--- a/package.json
+++ b/package.json
@@ -6,9 +6,8 @@
     "test": "pulp test"
   },
   "devDependencies": {
-    "pulp": "^12.0.1",
+    "pulp": "^12.2.0",
     "purescript-psa": "^0.6.0",
-    "purescript": "^0.11.1",
     "rimraf": "^2.6.1"
   }
-}
+}
\ No newline at end of file
diff --git a/src/Data/Argonaut/Decode/Class.purs b/src/Data/Argonaut/Decode/Class.purs
index b60895c..7dac424 100644
--- a/src/Data/Argonaut/Decode/Class.purs
+++ b/src/Data/Argonaut/Decode/Class.purs
@@ -12,7 +12,7 @@ import Data.Int (fromNumber)
 import Data.List (List(..), (:), fromFoldable)
 import Data.Map as M
 import Data.Maybe (maybe, Maybe(..))
-import Data.String (charAt)
+import Data.String (CodePoint, codePointAt)
 import Data.Traversable (traverse)
 import Data.Tuple (Tuple(..))
 import Foreign.Object as FO
@@ -63,10 +63,10 @@ instance decodeJsonString :: DecodeJson String where
 instance decodeJsonJson :: DecodeJson Json where
   decodeJson = Right
 
-instance decodeJsonChar :: DecodeJson Char where
+instance decodeJsonChar :: DecodeJson CodePoint where
   decodeJson j =
     maybe (Left $ "Expected character but found: " <> stringify j) Right
-      =<< charAt 0 <$> decodeJson j
+      =<< codePointAt 0 <$> decodeJson j
 
 instance decodeForeignObject :: DecodeJson a => DecodeJson (FO.Object a) where
   decodeJson
diff --git a/src/Data/Argonaut/Encode/Class.purs b/src/Data/Argonaut/Encode/Class.purs
index 7d2f16e..ba8fb4d 100644
--- a/src/Data/Argonaut/Encode/Class.purs
+++ b/src/Data/Argonaut/Encode/Class.purs
@@ -8,7 +8,9 @@ import Data.Int (toNumber)
 import Data.List (List(..), (:), toUnfoldable)
 import Data.Map as M
 import Data.Maybe (Maybe(..))
-import Data.String (singleton)
+import Data.String (CodePoint)
+import Data.String.CodePoints as CP
+import Data.String.CodeUnits as CU
 import Data.Tuple (Tuple(..))
 import Foreign.Object as FO
 
@@ -48,8 +50,11 @@ instance encodeJsonJString :: EncodeJson String where
 instance encodeJsonJson :: EncodeJson Json where
   encodeJson = identity
 
+instance encodeJsonCodePoint :: EncodeJson CodePoint where
+  encodeJson = encodeJson <<< CP.singleton
+
 instance encodeJsonChar :: EncodeJson Char where
-  encodeJson = encodeJson <<< singleton
+  encodeJson = encodeJson <<< CU.singleton
 
 instance encodeJsonArray :: EncodeJson a => EncodeJson (Array a) where
   encodeJson json = fromArray (encodeJson <$> json)