diff --git a/LICENSE b/LICENSE
new file mode 100644
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+++ b/LICENSE
@@ -0,0 +1,202 @@
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diff --git a/UNLICENSE b/UNLICENSE
deleted file mode 100644
--- a/UNLICENSE
+++ /dev/null
@@ -1,24 +0,0 @@
-This is free and unencumbered software released into the public domain.
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diff --git a/codex.cabal b/codex.cabal
--- a/codex.cabal
+++ b/codex.cabal
@@ -1,9 +1,9 @@
 name:                codex
-version:             0.0.1.6
+version:             0.0.1.7
 synopsis:            A ctags file generator for cabal project dependencies.
 description:         
   This tool download and cache the source code of packages in your local hackage,
-  he can then use this cache to generate `tags` files aggregating the sources of all the dependencies of your cabal projects.
+  it can then use this cache to generate `tags` files aggregating the sources of all the dependencies of your cabal projects.
   . 
   You basically do `codex update` in your cabal project directory and you'll get a `codex.tags` file
   that you can use in your favorite text editor.
@@ -11,8 +11,8 @@
   Usage overview can be found in the <http://github.com/aloiscochard/codex#codex README>.
 
 homepage:            http://github.com/aloiscochard/codex
-license:             OtherLicense
-license-file:        UNLICENSE
+license:             Apache-2.0
+license-file:        LICENSE
 author:              Alois Cochard
 maintainer:          alois.cochard@gmail.com
 category:            Development
@@ -25,6 +25,7 @@
   ghc-options:       -fwarn-incomplete-patterns
   exposed-modules:
     Codex
+    Codex.Project
     Codex.Internal
     Distribution.Hackage.Utils
   build-depends:       
diff --git a/src/Codex/Project.hs b/src/Codex/Project.hs
new file mode 100644
--- /dev/null
+++ b/src/Codex/Project.hs
@@ -0,0 +1,55 @@
+module Codex.Project where
+
+import Control.Exception (try, SomeException)
+import Data.Functor
+import Data.Maybe
+import Data.String.Utils
+import Data.Traversable (traverse)
+import Distribution.InstalledPackageInfo
+import Distribution.Hackage.DB (readHackage)
+import Distribution.Hackage.Utils
+import Distribution.PackageDescription
+import Distribution.PackageDescription.Parse
+import Distribution.Simple.Configure
+import Distribution.Simple.LocalBuildInfo
+import Distribution.Simple.PackageIndex
+import Distribution.Package
+import Distribution.Verbosity
+import System.Directory
+import System.FilePath
+
+import qualified Data.List as List
+
+import Codex.Internal
+
+findPackageDescription :: FilePath -> IO (Maybe GenericPackageDescription)
+findPackageDescription root = do
+  files <- getDirectoryContents root
+  traverse (readPackageDescription silent) $ List.find (endswith ".cabal") files
+
+resolveCurrentProjectDependencies :: IO (PackageIdentifier, [PackageIdentifier])
+resolveCurrentProjectDependencies = resolveProjectDependencies "."
+
+resolveProjectDependencies :: FilePath -> IO (PackageIdentifier, [PackageIdentifier])
+resolveProjectDependencies root = do
+  pd <- maybe (error "No cabal file found.") id <$> findPackageDescription root
+  xs <- either (fallback pd) return =<< resolveProjectInstalledDependencies root
+  return (identifier pd, xs) where
+    fallback pd e = do
+      putStrLn $ concat ["cabal: ", show e]
+      putStrLn "codex: *warning* falling back on dependency resolution using hackage"
+      resolveWithHackage pd
+    resolveWithHackage pd = do
+      db <- readHackage
+      return $ identifier <$> resolveDependencies db pd
+
+resolveProjectInstalledDependencies :: FilePath -> IO (Either SomeException [PackageIdentifier])
+resolveProjectInstalledDependencies root = try $ do
+  lbi <- getPersistBuildConfig distPref
+  let pkg   = localPkgDescr lbi
+      ipkgs = installedPkgs lbi
+      clbis = snd <$> allComponentsInBuildOrder lbi
+      pkgs  = componentPackageDeps =<< clbis
+      xs = fmap sourcePackageId $ (maybeToList . lookupInstalledPackageId ipkgs) =<< fmap fst pkgs
+  return xs where
+    distPref = joinPath [root, "dist"]
diff --git a/src/Main.hs b/src/Main.hs
--- a/src/Main.hs
+++ b/src/Main.hs
@@ -5,26 +5,24 @@
 import Control.Monad
 import Control.Monad.Trans.Either hiding (left, right)
 import Data.Either
-import Data.Traversable (traverse)
+import Data.Functor
 import Data.String.Utils
+import Data.Traversable (traverse)
 import Data.Yaml
-import Distribution.Hackage.DB (readHackage)
-import Distribution.PackageDescription
-import Distribution.PackageDescription.Parse
+import Distribution.Hackage.Utils (getHackagePath)
 import Distribution.Text
-import Distribution.Verbosity
 import GHC.Generics
+import Paths_codex (version)
 import System.Directory
 import System.Environment
 import System.FilePath
 import System.Exit
 
-import qualified Data.List as List
-
-import Distribution.Hackage.Utils
-
 import Codex
+import Codex.Project (resolveCurrentProjectDependencies)
 
+-- TODO Implement workspace resolution mechanism
+-- TODO Add 'cache dump' to dump all tags in stdout (usecase: pipe to grep)
 -- TODO Use a mergesort algorithm for `assembly`
 -- TODO Better error handling and fine grained retry
 
@@ -35,11 +33,6 @@
     Left ls -> fmap (left (++ ls)) x
     Right r -> return $ Right r
 
-getCurrentProject :: IO (Maybe GenericPackageDescription)
-getCurrentProject = do
-  files <- getDirectoryContents $ joinPath ["."]
-  traverse (readPackageDescription silent) $ List.find (endswith ".cabal") files
-
 tagsFile :: FilePath
 tagsFile = joinPath ["codex.tags"]
 
@@ -56,31 +49,33 @@
       return . fmap (fp </>) $ filter (not . startswith ".") xs
 
 update :: Codex -> Bool -> IO ()
-update cx force = getCurrentProject >>= resolve where
-  resolve Nothing = putStrLn "No cabal file found."
-  resolve (Just project) = do
-    dependencies <- fmap (\db -> resolveDependencies db project) readHackage
-    shouldUpdate <- runEitherT . isUpdateRequired tagsFile $ fmap identifier dependencies
-    when (either (const True) id shouldUpdate || force) $ do
+update cx force = do
+    (project, dependencies) <- resolveCurrentProjectDependencies
+    shouldUpdate <- either (const True) id <$> (runEitherT $ isUpdateRequired tagsFile dependencies)
+    if (shouldUpdate || force) then do
       fileExist <- doesFileExist tagsFile
       when fileExist $ removeFile tagsFile 
-      putStrLn $ concat ["Updating ", display . identifier $ project]
-      results <- traverse (retrying 3 . runEitherT . getTags . identifier) dependencies 
+      putStrLn $ concat ["Updating ", display project]
+      results <- traverse (retrying 3 . runEitherT . getTags) dependencies 
       traverse (putStrLn . show) . concat $ lefts results
-      generate dependencies where
-        getTags i = status cx i >>= \x -> case x of
-          (Source Tagged)   -> return ()
-          (Source Untagged) -> tags cx i >>= (const $ getTags i)
-          (Archive)         -> extract cx i >>= (const $ getTags i)
-          (Remote)          -> fetch cx i >>= (const $ getTags i)
-        generate xs = do 
-          res <- runEitherT $ assembly cx (fmap identifier xs) tagsFile
-          either (putStrLn . show) (const $ return ()) res
+      generate dependencies 
+    else 
+      putStrLn "Nothing to update."
+    where
+      getTags i = status cx i >>= \x -> case x of
+        (Source Tagged)   -> return ()
+        (Source Untagged) -> tags cx i >>= (const $ getTags i)
+        (Archive)         -> extract cx i >>= (const $ getTags i)
+        (Remote)          -> fetch cx i >>= (const $ getTags i)
+      generate xs = do 
+        res <- runEitherT $ assembly cx xs tagsFile
+        either (putStrLn . show) (const $ return ()) res
 
 help :: IO ()
 help = putStrLn $
   unlines [ "Usage: codex [update] [cache clean] [set tagger [hasktags|ctags]]"
           , "             [--help]"
+          , "             [--version]"
           , ""
           , " update                Synchronize the `codex.tags` file in the current cabal project directory"
           , " update --force        Discard `codex.tags` file hash and force regeneration"
@@ -99,6 +94,7 @@
     run cx ["update", "--force"]  = update cx True
     run cx ["set", "tagger", "ctags"]     = encodeConfig $ cx { tagsCmd = taggerCmd Ctags }
     run cx ["set", "tagger", "hasktags"]  = encodeConfig $ cx { tagsCmd = taggerCmd Hasktags }
+    run cx ["--version"] = putStrLn $ concat ["codex: ", display version]
     run cx ["--help"] = help
     run cx []         = help
     run cx (x:_)      = do