diff --git a/LICENSE b/LICENSE
new file mode 100644
--- /dev/null
+++ b/LICENSE
@@ -0,0 +1,30 @@
+Copyright (c) 2015, Athan Clark
+
+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 Athan Clark 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/src/Control/Monad/State/Sub.hs b/src/Control/Monad/State/Sub.hs
new file mode 100644
--- /dev/null
+++ b/src/Control/Monad/State/Sub.hs
@@ -0,0 +1,26 @@
+{-# LANGUAGE
+    MultiParamTypeClasses
+  , FlexibleInstances
+  #-}
+
+module Control.Monad.State.Sub where
+
+import Data.Set.Class as Sets
+import Control.Monad.State
+import Control.Monad.Reader
+
+
+-- | > lookup i =<< (putSingle x >> getTotal) ~ return (Just x)
+class MonadSubState i a s m where
+  getTotal  :: m s
+  putSingle :: a -> m ()
+
+instance ( HasInsertWith i a s
+         , MonadState s m
+         , MonadReader i m
+         ) => MonadSubState i a s m where
+  getTotal = get
+  putSingle x = do
+    i <- ask
+    s <- get
+    put $ insertWith i x s
diff --git a/sub-state.cabal b/sub-state.cabal
new file mode 100644
--- /dev/null
+++ b/sub-state.cabal
@@ -0,0 +1,40 @@
+Name:                   sub-state
+Version:                0.0.0.1
+Author:                 Athan Clark <athan.clark@gmail.com>
+Maintainer:             Athan Clark <athan.clark@gmail.com>
+License:                BSD3
+License-File:           LICENSE
+Synopsis:               Get the total, put a single element
+Description:
+  Restrain your data modification to /insert/ minimal amounts, while allowing
+  read access to the whole set.
+Cabal-Version:          >= 1.10
+Build-Type:             Simple
+Category:               Control
+
+Library
+  Default-Language:     Haskell2010
+  HS-Source-Dirs:       src
+  GHC-Options:          -Wall
+  Exposed-Modules:      Control.Monad.State.Sub
+  Build-Depends:        base >= 4.6 && < 5
+                      , sets
+                      , mtl
+
+Test-Suite spec
+  Type:                 exitcode-stdio-1.0
+  Default-Language:     Haskell2010
+  Hs-Source-Dirs:       src
+                      , test
+  Ghc-Options:          -Wall
+  Main-Is:              Spec.hs
+  Build-Depends:        base
+                      , tasty
+                      , tasty-quickcheck
+                      , tasty-hunit
+                      , QuickCheck
+                      , quickcheck-instances
+
+Source-Repository head
+  Type:                 git
+  Location:             https://github.com/athanclark/sub-state
diff --git a/test/Spec.hs b/test/Spec.hs
new file mode 100644
--- /dev/null
+++ b/test/Spec.hs
@@ -0,0 +1,13 @@
+module Spec where
+
+import Control.Monad.State.SubSpec
+
+import Test.Tasty
+
+
+main :: IO ()
+main = defaultMain tests
+
+tests :: TestTree
+tests = testGroup "Testing..."
+  [spec]