diff --git a/input.txt b/input.txt
deleted file mode 100644
index 1ba8437..0000000
--- a/input.txt
+++ /dev/null
@@ -1,4 +0,0 @@
-1abc2
-pqr3stu8vwx
-a1b2c3d4e5f
-treb7uchet
\ No newline at end of file
diff --git a/justfile b/justfile
index 1c3a9d2..ff83977 100644
--- a/justfile
+++ b/justfile
@@ -10,7 +10,7 @@ test:
 
 # Run the project with ghcid auto-recompile
 run:
-   stack build --file-watch --fast --ghc-options='-O0 -fbyte-code' --exec "elara --dump-shunted --dump-core --dump-typed --run"
+   stack build --file-watch --fast --ghc-options='-O1 -fbyte-code' --exec "elara --dump-shunted --dump-core --dump-typed --run"
 
 # Start Hoogle server for project dependencies
 docs:
diff --git a/list.elr b/list.elr
index f2f4486..881d676 100644
--- a/list.elr
+++ b/list.elr
@@ -5,4 +5,54 @@ def isEmpty : [a] -> Bool
 let isEmpty l =
     match l with
         [] -> True
-        (x::xs) -> False
\ No newline at end of file
+        (x::xs) -> False
+
+def length : [a] -> Int
+let length l =
+    match l with
+        [] -> 0
+        (x::xs) -> 1 + length xs
+
+def sum : [Int] -> Int	
+let sum a = 	
+    match a with	
+      [] -> 0	
+      (x::xs) -> x + sum xs
+
+def reverse : [a] -> [a]	
+let reverse a = 	
+    match a with	
+      [] -> []	
+      (x::xs) -> reverse xs <> [x]	
+
+def head : [a] -> a	
+let head a = 	
+    match a with	
+      [] -> undefined	
+      (x::xs) -> x	
+
+def last : [a] -> a	
+let last a = 	
+    match a with	
+      [] -> undefined	
+      (x::xs) -> if xs == [] then x else last xs	
+
+
+def map : (a -> b) -> [a] -> [b]	
+let map f a = 	
+    match a with	
+      [] -> []	
+      (x::xs) -> f x :: map f xs	
+
+def filter : (a -> Bool) -> [a] -> [a]	
+let filter f a = 	
+    match a with	
+      [] -> []	
+      (x::xs) -> if f x then x :: filter f xs else filter f xs	
+
+infixr 5 <>	
+def (<>) : [a] -> [a] -> [a]	
+let (<>) a b = 	
+    match a with	
+      [] -> b	
+      (x::xs) -> x :: (xs <> b)	
\ No newline at end of file
diff --git a/prelude.elr b/prelude.elr
index 92cd66b..0b7e944 100644
--- a/prelude.elr
+++ b/prelude.elr
@@ -42,50 +42,13 @@ let charToInt c =
     else if c == '9' then 9	
     else -1	
 
-infixr 5 <>	
-def (<>) : [a] -> [a] -> [a]	
-let (<>) a b = 	
-    match a with	
-      [] -> b	
-      (x::xs) -> x :: (xs <> b)	
+
 
 infixr 5 ++	
 def (++) : String -> String -> String	
 let (++) a b = listToString ((stringToList a) <> (stringToList b))	
 
 
-def reverse : [a] -> [a]	
-let reverse a = 	
-    match a with	
-      [] -> []	
-      (x::xs) -> reverse xs <> [x]	
-
-
-def head : [a] -> a	
-let head a = 	
-    match a with	
-      [] -> undefined	
-      (x::xs) -> x	
-
-def last : [a] -> a	
-let last a = 	
-    match a with	
-      [] -> undefined	
-      (x::xs) -> if xs == [] then x else last xs	
-
-
-def map : (a -> b) -> [a] -> [b]	
-let map f a = 	
-    match a with	
-      [] -> []	
-      (x::xs) -> f x :: map f xs	
-
-def filter : (a -> Bool) -> [a] -> [a]	
-let filter f a = 	
-    match a with	
-      [] -> []	
-      (x::xs) -> if f x then x :: filter f xs else filter f xs	
-
 def not : Bool -> Bool	
 let not a = 	
     if a then False else True	
@@ -95,18 +58,6 @@ let (/=) a b =
     not (a == b)	
 
 
-def sum : [Int] -> Int	
-let sum a = 	
-    match a with	
-      [] -> 0	
-      (x::xs) -> x + sum xs	
-
-def isEmpty : [a] -> Bool	
-let isEmpty a =	
-    match a with	
-      [] -> True
-      (x::xs) -> False
-
 def listToString : [Char] -> String
 let listToString a =	
     match a with	
diff --git a/source.elr b/source.elr
index d8579ae..ef491c6 100644
--- a/source.elr
+++ b/source.elr
@@ -4,11 +4,5 @@ import Elara.Prim
 def l : List Int
 let l = [1, 2, 3]
 
-def map : (a -> b) -> List a -> List b
-let map f l = 
-    match l with
-        Nil -> Nil
-        Cons x xs -> Cons (f x) (map f xs)
-
 let main = 
-    print (stringToList "hello")
+    print (stringToList "hello" |> map identity |> length)