diff --git a/LICENSE b/LICENSE
--- a/LICENSE
+++ b/LICENSE
@@ -1,30 +1,21 @@
-Copyright Lucas David Traverso (c) 2018
-
-All rights reserved.
-
-Redistribution and use in source and binary forms, with or without
-modification, are permitted provided that the following conditions are met:
+MIT License
 
-    * Redistributions of source code must retain the above copyright
-      notice, this list of conditions and the following disclaimer.
+Copyright (c) 2019 Lucas David Traverso
 
-    * 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.
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
 
-    * Neither the name of Lucas David Traverso nor the names of other
-      contributors may be used to endorse or promote products derived
-      from this software without specific prior written permission.
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
 
-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.
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.
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/conferer.cabal b/conferer.cabal
--- a/conferer.cabal
+++ b/conferer.cabal
@@ -4,10 +4,10 @@
 --
 -- see: https://github.com/sol/hpack
 --
--- hash: a139753b9c1bc2266c7b90feb57d35995b1b57ffa23dcf6f7d8a2b8dad4a7238
+-- hash: a30bb964060c98a8149ad2b98ca2bfc764e40aac9a70c603ab2e27722c25d131
 
 name:           conferer
-version:        0.1.0.1
+version:        0.1.0.2
 synopsis:       Configuration management library
 
 description:    Library to abstract the parsing of many haskell config values from different config sources
diff --git a/src/Conferer.hs b/src/Conferer.hs
--- a/src/Conferer.hs
+++ b/src/Conferer.hs
@@ -16,13 +16,13 @@
   --   command line arguments of @.properties@ files
   --
   -- @
-  -- > import Conferer
-  -- > import Conferer.FetchFromConfig.Warp () -- from package conferer-warp
-  -- >
-  -- > main = do
-  -- >   config <- 'defaultConfig' \"awesomeapp\"
-  -- >   warpSettings <- 'getFromConfig' \"warp\" config
-  -- >   runSettings warpSettings application
+  -- import Conferer
+  -- import Conferer.FetchFromConfig.Warp () -- from package conferer-warp
+  --
+  -- main = do
+  --   config <- 'defaultConfig' \"awesomeapp\"
+  --   warpSettings <- 'getFromConfig' \"warp\" config
+  --   runSettings warpSettings application
   -- @
   --
   -- In the above example we see that we are getting a configuration value for
diff --git a/src/Conferer/FetchFromConfig/Basics.hs b/src/Conferer/FetchFromConfig/Basics.hs
--- a/src/Conferer/FetchFromConfig/Basics.hs
+++ b/src/Conferer/FetchFromConfig/Basics.hs
@@ -2,7 +2,7 @@
 module Conferer.FetchFromConfig.Basics where
 
 import           Conferer.Types
-import           Conferer.Core (getKey)
+import           Conferer.Core (getKey, (/.))
 import           Data.Text (Text)
 import qualified Data.Text as Text
 import qualified Data.Text.Encoding as Text
@@ -47,3 +47,21 @@
 fetchFromConfigWith :: (Text -> Maybe a) -> Key -> Config -> IO (Either Text a)
 fetchFromConfigWith parseValue key config =
   (fromValueWith parseValue key =<<) <$> getKey key config
+
+-- | Concatenate many transformations to the config based on keys and functions
+findKeyAndApplyConfig ::
+  FetchFromConfig newvalue
+  => Config -- ^ Complete config
+  -> Key -- ^ Key that indicates the part of the config that we care about
+  -> Key -- ^ Key that we use to find the config (usually concatenating with the
+         -- other key)
+  -> (newvalue -> config -> config) -- ^ Function that knows how to use the
+                                    -- value to update the config
+  -> Either Text config -- ^ Result of the last config updating
+  -> IO (Either Text config) -- ^ Updated config
+findKeyAndApplyConfig config k relativeKey f (Right customConfig) =
+  fetch (k /. relativeKey) config
+    >>= \case
+      Left a -> return $ Right customConfig
+      Right a -> return $ Right $ f a customConfig
+findKeyAndApplyConfig config k relativeKey f (Left e) = return $ Left e