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diff --git a/Math/LinProg/LPSolve.hs b/Math/LinProg/LPSolve.hs
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+++ b/Math/LinProg/LPSolve.hs
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+{-# LANGUAGE ViewPatterns #-}
+
+module Math.LinProg.LPSolve where
+
+import Control.Applicative
+import Control.Monad
+import Data.List
+import Control.Lens
+import Math.LinProg.LPSolve.FFI hiding (solve)
+import qualified Math.LinProg.LPSolve.FFI as F
+import Math.LinProg.Compile
+import Math.LinProg.Types
+import qualified Data.Map as M
+import Prelude hiding (EQ)
+
+solve :: (Eq v, Ord v) => LinProg Double v () -> IO (Either (Maybe ResultCode) [(v, Double)])
+solve (compile -> lp) = do
+    model <- makeLP nconstr nvars
+    case model of
+      Nothing -> return (Left Nothing)
+      Just m' -> with m' $ \m -> do
+
+        -- Eqs
+        forM_ (zip [1..] $ lp ^. equals) $ \(i, eq) ->
+          forM_ (M.keys varLUT) $ \v -> do
+            let w = getVar v $ fst eq
+                c = negate $ snd eq
+            when (w /= 0) $ do
+              setMat m i (varLUT M.! v) w
+              setConstrType m i EQ
+              setRHS m i c
+              return ()
+
+        -- Leqs
+        forM_ (zip [1+nequals..] $ lp ^. leqs) $ \(i, eq) ->
+          forM_ (M.keys varLUT) $ \v -> do
+            let w = getVar v $ fst eq
+                c = negate $ snd eq
+            when (w /= 0) $ do
+              setMat m i (varLUT M.! v) w
+              setConstrType m i LE
+              setRHS m i c
+              return ()
+
+        -- Objective
+        forM_ (M.keys varLUT) $ \v -> do
+          let w = getVar v $ lp ^. objective
+          when (w /= 0) $ void $ setMat m 0 (varLUT M.! v) w
+
+        res <- F.solve m
+        case res of
+          Optimal -> do
+            sol <- snd <$> getSol nvars m
+            return $ Right (zip (M.keys varLUT) sol)
+          _ -> return $ Left (Just res)
+  where
+    nconstr = length allConstr
+    nvars = M.size varLUT
+    nequals = length (lp ^. equals)
+
+    allConstr = (lp ^. equals) ++ (lp ^. leqs)
+    varLUT = M.fromList $ zip (sort $ nub $ concatMap (vars . fst) allConstr) [1..]
+
+    with m f = do
+      r <- f m
+      freeLP m
+      return r