diff --git a/ChangeLog.md b/ChangeLog.md
new file mode 100644
--- /dev/null
+++ b/ChangeLog.md
@@ -0,0 +1,8 @@
+# Changelog for within
+
+## v0.0.1.o
+
+* Add Within Type based on [path](https://hackage.haskell.org/package/path).
+Within is a path within another path.
+* Add several functions for moving between directories and mapping source
+  names.
diff --git a/LICENSE b/LICENSE
new file mode 100644
--- /dev/null
+++ b/LICENSE
@@ -0,0 +1,30 @@
+Copyright Author name here (c) 2020
+
+All rights reserved.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are met:
+
+    * Redistributions of source code must retain the above copyright
+      notice, this list of conditions and the following disclaimer.
+
+    * Redistributions in binary form must reproduce the above
+      copyright notice, this list of conditions and the following
+      disclaimer in the documentation and/or other materials provided
+      with the distribution.
+
+    * Neither the name of Author name here nor the names of other
+      contributors may be used to endorse or promote products derived
+      from this software without specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
diff --git a/README.md b/README.md
new file mode 100644
--- /dev/null
+++ b/README.md
@@ -0,0 +1,8 @@
+# Within
+
+`Within` is a type for simply scoping well-typed paths. A `Within a t` is
+just a `Path Rel t` inside a `Path a Dir`. This is useful for when you want
+to keep track of a filepath within a parent folder and need the extra degree
+of articulation.
+
+Early release, subject to change.
diff --git a/Setup.hs b/Setup.hs
new file mode 100644
--- /dev/null
+++ b/Setup.hs
@@ -0,0 +1,2 @@
+import Distribution.Simple
+main = defaultMain
diff --git a/src/Within.hs b/src/Within.hs
new file mode 100644
--- /dev/null
+++ b/src/Within.hs
@@ -0,0 +1,65 @@
+{-# LANGUAGE DeriveGeneric #-}
+module Within (
+  Within(..)
+, fromWithin
+, toWithin
+, within
+, asWithin
+, whatLiesWithin
+, mapWithin
+, mapWithinT
+, moveWithin
+, moveWithinT
+, blinkWithin
+, moveAndMapT
+, blinkAndMapT
+) where
+
+import Control.Monad.Catch
+import Data.Typeable
+import GHC.Generics
+import Path
+
+newtype Within a t = Within (Path a Dir, Path Rel t)
+  deriving (Typeable, Generic, Eq, Show)
+
+fromWithin :: Within a t -> Path a t
+fromWithin (Within (x,y)) = x </> y
+
+toWithin :: Path a Dir -> Path Rel t -> Within a t
+toWithin = flip within
+
+within :: Path Rel t -> Path a Dir -> Within a t
+within y x = Within (x,y)
+
+asWithin :: MonadThrow m => Path a t -> Path a Dir -> m (Within a t)
+asWithin x y = stripProperPrefix y x >>= \z -> return (Within (y, z))
+
+whatLiesWithin :: Within a t -> Path Rel t
+whatLiesWithin (Within (_,y)) = y
+
+mapWithin :: (Path Rel s -> Path Rel t) -> Within a s -> Within a t
+mapWithin f (Within (x,y)) = Within (x, f y)
+
+mapWithinT :: MonadThrow m => (Path Rel s -> m (Path Rel t)) -> Within a s -> m (Within a t)
+mapWithinT f (Within (x,y)) = f y >>= \z -> return (Within (x, z))
+
+blinkWithin :: Path b Dir -> Within a t -> Within b t
+blinkWithin = moveWithin . const
+
+moveWithin :: (Path a Dir -> Path b Dir) -> Within a t -> Within b t
+moveWithin f (Within (x,y)) = Within (f x, y)
+
+moveWithinT :: MonadThrow m => (Path a Dir -> m (Path b Dir)) -> Within a t -> m (Within b t)
+moveWithinT f (Within (x,y)) = f x >>= \z -> return (Within (z,y))
+
+blinkAndMapT :: MonadThrow m => Path b Dir -> (Path Rel s -> m (Path Rel t)) -> Within a s -> m (Within b t)
+blinkAndMapT k g (Within (_,y)) = do
+  y' <- g y
+  return $ Within (k, y')
+
+moveAndMapT :: MonadThrow m => (Path a Dir -> m (Path b Dir)) -> (Path Rel s -> m (Path Rel t)) -> Within a s -> m (Within b t)
+moveAndMapT f g (Within (x,y)) = do
+  x' <- f x
+  y' <- g y
+  return $ Within (x', y')
diff --git a/within.cabal b/within.cabal
new file mode 100644
--- /dev/null
+++ b/within.cabal
@@ -0,0 +1,35 @@
+cabal-version: 1.12
+
+-- This file has been generated from package.yaml by hpack version 0.33.0.
+--
+-- see: https://github.com/sol/hpack
+--
+-- hash: b387258ad76af8d3a2c66d14e6c7814a0c5b23ceabe75719dbbb8aae3e8a6bde
+
+name:           within
+version:        0.0.1.0
+synopsis:       A path within another path.
+description:    Simple type for representing a well-typed path within another path. Useful for when you need to jump between directories and change filenames independently. Uses the path library.
+category:       Filesystem
+author:         Daniel Firth
+maintainer:     dan.firth@homotopic.tech
+copyright:      2020 Daniel Firth
+license:        MIT
+license-file:   LICENSE
+build-type:     Simple
+extra-source-files:
+    README.md
+    ChangeLog.md
+
+library
+  exposed-modules:
+      Within
+  other-modules:
+      Paths_within
+  hs-source-dirs:
+      src
+  build-depends:
+      base >=4.7 && <5
+    , exceptions
+    , path
+  default-language: Haskell2010