diff --git a/.travis.yml b/.travis.yml
index 15bacc0..273d6cd 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -1,7 +1,7 @@
 language: node_js
 dist: trusty
 sudo: required
-node_js: 6
+node_js: 9
 install:
   - npm install -g bower
   - npm install
diff --git a/bower.json b/bower.json
index 80ee726..01571fa 100644
--- a/bower.json
+++ b/bower.json
@@ -17,17 +17,17 @@
     "package.json"
   ],
   "dependencies": {
-    "purescript-console": "^3.0.0",
-    "purescript-exceptions": "^3.0.0",
-    "purescript-lists": "^4.0.0",
-    "purescript-partial": "^1.2.0",
-    "purescript-profunctor": "^3.0.0",
-    "purescript-strings": "^3.5.0",
-    "purescript-transformers": "^3.0.0",
-    "purescript-unsafe-coerce": "^3.0.0",
-    "purescript-typelevel-prelude": "^2.6.0"
+    "purescript-console": "^4.0.1",
+    "purescript-exceptions": "^4.0.0",
+    "purescript-lists": "^5.0.0",
+    "purescript-partial": "^2.0.0",
+    "purescript-profunctor": "^4.0.0",
+    "purescript-strings": "^4.0.0",
+    "purescript-transformers": "^4.1.0",
+    "purescript-unsafe-coerce": "^4.0.0",
+    "purescript-typelevel-prelude": "^3.0.0"
   },
   "devDependencies": {
-    "purescript-quickcheck": "^4.0.0"
+    "purescript-quickcheck": "^5.0.0"
   }
 }
diff --git a/package.json b/package.json
index da76be2..643f6a5 100644
--- a/package.json
+++ b/package.json
@@ -6,9 +6,9 @@
     "test": "pulp test"
   },
   "devDependencies": {
-    "pulp": "^11.0.0",
+    "pulp": "^12.3.0",
     "purescript-psa": "^0.5.0",
-    "purescript": "^0.11.1",
+    "purescript": "^0.12.0",
     "rimraf": "^2.5.4"
   }
 }
diff --git a/src/Pathy/Gen.purs b/src/Pathy/Gen.purs
index 5939c7b..823015f 100644
--- a/src/Pathy/Gen.purs
+++ b/src/Pathy/Gen.purs
@@ -21,7 +21,7 @@ import Data.Foldable (foldr)
 import Data.List as L
 import Data.NonEmpty ((:|))
 import Data.String.Gen as SG
-import Data.String.NonEmpty (cons)
+import Data.String.NonEmpty.CodeUnits (cons)
 import Pathy (AbsDir, AbsFile, AbsPath, Dir, File, RelDir, RelFile, RelPath, (</>))
 import Pathy as P
 
diff --git a/src/Pathy/Name.purs b/src/Pathy/Name.purs
index c3043c0..186a39b 100644
--- a/src/Pathy/Name.purs
+++ b/src/Pathy/Name.purs
@@ -6,7 +6,7 @@ import Data.Maybe (Maybe(..), fromMaybe)
 import Data.Newtype (class Newtype)
 import Data.String as S
 import Data.String.NonEmpty (NonEmptyString)
-import Data.String.NonEmpty as NES
+import Data.String.NonEmpty.CodeUnits as NES
 import Data.Symbol (class IsSymbol, SProxy(..))
 import Data.Symbol (reflectSymbol) as Symbol
 import Pathy.Phantom (kind DirOrFile)
@@ -34,7 +34,7 @@ instance showName :: Show (Name a) where
 -- | splitName (Name "foo.baz") == { name: "foo",  extension: Just "baz" }
 -- | ```
 -- | _Note, in real code all strings from this examples would be `NonEmptyString`._
--- | 
+-- |
 -- | Also for any `Name` this property holds:
 -- | ```purescript
 -- | joinName <<< splitName = id
@@ -61,7 +61,7 @@ joinName { name, ext } = Name $ case ext of
   Just ext' -> name <> NES.singleton '.' <> ext'
 
 -- | Retrieves the extension of a name. also see [`splitName`](#v:splitName)
--- | 
+-- |
 -- | ```purescript
 -- | extension (Name ".foo")    == Nothing
 -- | extension (Name "foo.")    == Nothing
@@ -76,7 +76,7 @@ extension = splitName >>> _.ext
 -- | or modified. see [`splitName`](#v:splitName) and [`joinName`](#v:joinName)
 -- | for how a `Name` is split into name and extention part and joined back
 -- | into a `Name`.
--- | 
+-- |
 -- | Also for any `Name` this property holds:
 -- | ```purescript
 -- | alterExtension id = id
@@ -89,7 +89,7 @@ alterExtension
 alterExtension f n =
   let spn = splitName n
   in joinName spn{ext = f spn.ext}
-  
+
 -- | A class for creating `Name` values from type-level strings. This allows us
 -- | to guarantee that a name is not empty at compile-time.
 class IsName sym where
diff --git a/src/Pathy/Parser.purs b/src/Pathy/Parser.purs
index e7f4605..cb3a9b0 100644
--- a/src/Pathy/Parser.purs
+++ b/src/Pathy/Parser.purs
@@ -16,9 +16,11 @@ import Data.Either (Either(..), either)
 import Data.List (List(..), (:))
 import Data.List as L
 import Data.Maybe (Maybe(..))
-import Data.String as S
+import Data.String (split) as S
+import Data.String.CodeUnits (take, takeRight) as S
 import Data.String.NonEmpty (NonEmptyString)
 import Data.String.NonEmpty as NES
+import Data.String.Pattern (Pattern(..)) as S
 import Pathy.Name (Name(..))
 import Pathy.Path (AbsDir, AbsFile, Path, RelDir, RelFile, currentDir, extendPath, parentOf, rootDir)
 import Pathy.Phantom (class IsRelOrAbs, Dir)
diff --git a/src/Pathy/Phantom.purs b/src/Pathy/Phantom.purs
index a17fac2..2e4b33e 100644
--- a/src/Pathy/Phantom.purs
+++ b/src/Pathy/Phantom.purs
@@ -24,8 +24,8 @@ class IsRelOrAbs (a :: RelOrAbs) where
     -> f a b
     -> r
 
-instance relIsRelOrAbs :: IsRelOrAbs Rel where onRelOrAbs f _ = f id
-instance absIsRelOrAbs :: IsRelOrAbs Abs where onRelOrAbs _ f = f id
+instance relIsRelOrAbs :: IsRelOrAbs Rel where onRelOrAbs f _ = f identity
+instance absIsRelOrAbs :: IsRelOrAbs Abs where onRelOrAbs _ f = f identity
 
 -- | Folds over a value that uses `RelOrAbs` to produce a new result.
 foldRelOrAbs
@@ -59,8 +59,8 @@ class IsDirOrFile (b :: DirOrFile) where
     -> f b
     -> r
 
-instance isDirOrFileDir :: IsDirOrFile Dir where onDirOrFile f _ = f id
-instance isDirOrFileFile :: IsDirOrFile File where onDirOrFile _ f = f id
+instance isDirOrFileDir :: IsDirOrFile Dir where onDirOrFile f _ = f identity
+instance isDirOrFileFile :: IsDirOrFile File where onDirOrFile _ f = f identity
 
 -- | Folds over a value that uses `DirOrFile` to produce a new result.
 foldDirOrFile
diff --git a/src/Pathy/Printer.purs b/src/Pathy/Printer.purs
index 709a402..423ca2c 100644
--- a/src/Pathy/Printer.purs
+++ b/src/Pathy/Printer.purs
@@ -16,16 +16,18 @@ import Prelude
 
 import Data.Foldable (fold)
 import Data.Maybe (Maybe(..), maybe)
-import Data.Monoid (class Monoid)
 import Data.Newtype (class Newtype, un, unwrap)
-import Data.String as Str
+import Data.String (Pattern(..)) as Str
+import Data.String.CodeUnits (singleton) as Str
 import Data.String.NonEmpty (NonEmptyString)
-import Data.String.NonEmpty as NES
+import Data.String.NonEmpty (NonEmptyReplacement(..), replaceAll, toString, unsafeFromString) as NES
+import Data.String.NonEmpty.CodeUnits (cons, singleton) as NES
 import Partial.Unsafe (unsafePartial)
 import Pathy.Name (Name)
 import Pathy.Path (Path, foldPath, (</>))
 import Pathy.Phantom (class IsDirOrFile, class IsRelOrAbs, Dir, Rel, foldDirOrFile, foldRelOrAbs, kind DirOrFile, kind RelOrAbs)
 import Pathy.Sandboxed (SandboxedPath, sandboxRoot, unsandbox)
+import Prim.TypeError (class Warn, Text)
 
 -- | A `Printer` defines options for printing paths.
 -- |
@@ -81,7 +83,7 @@ printPath r sp =
   in
     printPathRep
       r
-      (foldRelOrAbs (root </> _) id p)
+      (foldRelOrAbs (root </> _) identity p)
 
 -- | Prints a `SandboxedPath` into its canonical `String` representation, using
 -- | the specified printer. This will print a relative path if `b ~ Rel`, which
@@ -100,7 +102,7 @@ unsafePrintPath r sp = printPathRep r (unsandbox sp)
 -- | compile time as a reminder!
 debugPrintPath
   :: forall a b
-   . Warn "debugPrintPath usage"
+   . Warn (Text "debugPrintPath usage")
   => IsRelOrAbs a
   => IsDirOrFile b
   => Printer
@@ -155,7 +157,7 @@ instance semigroupEscaper :: Semigroup Escaper where
   append (Escaper e1) (Escaper e2) = Escaper (e1 <<< e2)
 
 instance monoidEscaper :: Monoid Escaper where
-  mempty = Escaper id
+  mempty = Escaper identity
 
 -- | An escaper that replaces all `'/'` characters in a name with `'-'`s.
 slashEscaper :: Escaper
diff --git a/src/Pathy/Sandboxed.purs b/src/Pathy/Sandboxed.purs
index 81f0987..5240671 100644
--- a/src/Pathy/Sandboxed.purs
+++ b/src/Pathy/Sandboxed.purs
@@ -29,7 +29,7 @@ sandbox
   => Path Abs Dir
   -> Path a b
   -> Maybe (SandboxedPath a b)
-sandbox root = map (SandboxedPath root) <<< onRelOrAbs (go (root </> _)) (go id)
+sandbox root = map (SandboxedPath root) <<< onRelOrAbs (go (root </> _)) (go identity)
   where
     go :: forall p. (p -> Path Abs b) -> (p -> Path a b) -> p -> Maybe (Path a b)
     go f coe p =
diff --git a/test/Main.purs b/test/Main.purs
index af363b2..e7304b3 100644
--- a/test/Main.purs
+++ b/test/Main.purs
@@ -2,17 +2,18 @@ module Test.Main where
 
 import Prelude
 
-import Control.Monad.Eff (Eff)
-import Control.Monad.Eff.Console (CONSOLE, info)
-import Control.Monad.Eff.Exception (EXCEPTION, throw)
 import Data.Maybe (Maybe(..), maybe)
 import Data.Newtype (un)
 import Data.NonEmpty ((:|))
 import Data.String as Str
 import Data.String.NonEmpty (NonEmptyString)
-import Data.String.NonEmpty as NES
+import Data.String.NonEmpty (fromString) as NES
+import Data.String.NonEmpty.CodeUnits (singleton) as NES
 import Data.Symbol (SProxy(..))
 import Data.Tuple (Tuple(..))
+import Effect (Effect)
+import Effect.Console (info)
+import Effect.Exception (throw)
 import Pathy (class IsDirOrFile, class IsRelOrAbs, Abs, Dir, Name(..), Path, Rel, alterExtension, currentDir, debugPrintPath, dir, extension, file, in', joinName, parentOf, parseAbsDir, parseAbsFile, parseRelDir, parseRelFile, peel, posixParser, posixPrinter, printPath, relativeTo, rename, rootDir, sandbox, sandboxAny, splitName, unsandbox, windowsPrinter, (<..>), (<.>), (</>))
 import Pathy.Gen as PG
 import Pathy.Name (reflectName)
@@ -21,14 +22,14 @@ import Test.QuickCheck as QC
 import Test.QuickCheck.Gen as Gen
 import Unsafe.Coerce (unsafeCoerce)
 
-test :: forall a eff. Show a => Eq a => String -> a -> a -> Eff (console :: CONSOLE, exception :: EXCEPTION | eff) Unit
+test :: forall a. Show a => Eq a => String -> a -> a -> Effect Unit
 test name actual expected= do
   info $ "Test: " <> name
   if expected == actual
     then info $ "Passed: " <> (show expected)
     else throw $ "Failed:\n    Expected: " <> (show expected) <> "\n    Actual:   " <> (show actual)
 
-test' :: forall a b eff. IsRelOrAbs a => IsDirOrFile b => String -> Path a b -> String -> Eff (console :: CONSOLE, exception :: EXCEPTION | eff) Unit
+test' :: forall a b. IsRelOrAbs a => IsDirOrFile b => String -> Path a b -> String -> Effect Unit
 test' n p s = test n (printTestPath p) s
 
 pathPart ∷ Gen.Gen NonEmptyString
@@ -89,12 +90,12 @@ genAmbigiousName =
 checkAlterExtensionId :: Gen.Gen QC.Result
 checkAlterExtensionId = do
   n <- genAmbigiousName
-  pure $ alterExtension id n === id n
+  pure $ alterExtension identity n === identity n
 
 checkJoinSplitNameId :: Gen.Gen QC.Result
 checkJoinSplitNameId = do
   n <- genAmbigiousName
-  pure $ joinName (splitName n) === id n
+  pure $ joinName (splitName n) === identity n
 
 checkPeelIn :: forall b. IsDirOrFile b => Gen.Gen (Path Abs b) -> Gen.Gen QC.Result
 checkPeelIn gen = do
@@ -118,7 +119,7 @@ checkRelative gen = do
           <> "\n\trel:  " <> printTestPath rel
           <> "\n\tp1': " <> printTestPath p1'
 
-main :: QC.QC () Unit
+main :: Effect Unit
 main = do
   info "checking `parse <<< print` for `AbsDir`" *> QC.quickCheck parsePrintAbsDirPath
   info "checking `parse <<< print` for `AbsFile`" *> QC.quickCheck parsePrintAbsFilePath