diff --git a/2019/day12/day12.hs b/2019/day12/day12.hs
new file mode 100644
index 0000000..76b56d9
--- /dev/null
+++ b/2019/day12/day12.hs
@@ -0,0 +1,28 @@
+{-# LANGUAGE LambdaCase #-}
+
+import Data.List.Split
+import Linear.V3
+
+main = do
+    moons <- parseContent <$> readFile "testinput"
+    let velocity = replicate 4 $ V3 0 0 0
+    print $ energy $ step (moons,velocity) 1000
+
+removeJunk :: String -> String
+removeJunk xs = [ x | x <- xs, x `notElem` " <>xyz=" ]
+
+parseContent :: String -> [V3 Int]
+parseContent = map ((\[x,y,z]->V3 x y z) . map read . splitOn ",") . lines . removeJunk
+
+gravity :: [V3 Int] -> [V3 Int]
+gravity xs = [sum [signum $ x-y | x<-xs, y/=x] | y<-xs]
+
+step :: ([V3 Int],[V3 Int]) -> Int -> ([V3 Int],[V3 Int])
+step (moons,vel) 0 = (moons,vel)
+step (moons,vel) n = step (zipWith (+) moons newVel,newVel) (n-1)
+    where dVel = gravity moons
+          newVel = zipWith (+) vel dVel
+
+energy :: ([V3 Int],[V3 Int]) -> Int
+energy (x,y) = sum $ zipWith (*) (geten x) (geten y) where
+    geten = map (sum . abs)
diff --git a/2019/day12/input b/2019/day12/input
new file mode 100644
index 0000000..49300d0
--- /dev/null
+++ b/2019/day12/input
@@ -0,0 +1,4 @@
+<x=5, y=4, z=4>
+<x=-11, y=-11, z=-3>
+<x=0, y=7, z=0>
+<x=-13, y=2, z=10>