diff --git a/src/passes/operators/operators.ml b/src/passes/operators/operators.ml
index 47627a440..15ed4928a 100644
--- a/src/passes/operators/operators.ml
+++ b/src/passes/operators/operators.ml
@@ -165,6 +165,7 @@ module Simplify = struct
       ("Map.fold" , "MAP_FOLD") ;
       ("Map.empty" , "MAP_EMPTY") ;
       ("Map.literal" , "MAP_LITERAL" ) ;
+      ("Map.size" , "SIZE" ) ;
 
       ("String.length", "SIZE") ;
       ("String.size", "SIZE") ;
@@ -615,6 +616,7 @@ module Typer = struct
       map_update ;
       map_mem ;
       map_find ;
+      map_find_opt ;
       map_map ;
       map_fold ;
       map_iter ;
diff --git a/src/test/contracts/big_map.ligo b/src/test/contracts/big_map.ligo
index 461c2c206..8fb705ab5 100644
--- a/src/test/contracts/big_map.ligo
+++ b/src/test/contracts/big_map.ligo
@@ -27,34 +27,4 @@ function gf (const m : storage_) : int is begin skip end with get_force(23, m.0)
 function get (const m : storage_) : option(int) is
   begin
     skip
-  end with m.0[42]
-
-// the following is not supported (negative test cases):
-
-// const bm : storage_ = big_map
-//   144 -> 23 ;
-//   51 -> 23 ;
-//   42 -> 23 ;
-//   120 -> 23 ;
-//   421 -> 23 ;
-// end
-
-// type foobar is big_map(int, int)
-// const fb : foobar = big_map
-//   23 -> 0 ;
-//   42 -> 0 ;
-// end
-
-// function size_ (const m : storage_) : nat is
-//   block {skip} with (size(m.0))
-
-// function iter_op (const m : storage_) : int is
-//   var r : int := 0 ;
-//   function aggregate (const i : int ; const j : int) : unit is block { r := r + i + j } with unit ;
-//   block {
-//     map_iter(m.0 , aggregate) ;
-//   } with r ;
-
-// function map_op (const m : storage_) : storage_ is
-//   function increment (const i : int ; const j : int) : int is block { skip } with j + 1 ;
-//   block { skip } with map_map(m.0 , increment) ;
+  end with m.0[42]
\ No newline at end of file
diff --git a/src/test/contracts/big_map.mligo b/src/test/contracts/big_map.mligo
new file mode 100644
index 000000000..d032fad8c
--- /dev/null
+++ b/src/test/contracts/big_map.mligo
@@ -0,0 +1,12 @@
+type storage_ = ((int, int) big_map * unit)
+
+let set_ (n : int) (m : storage_) : storage_ =
+    (Map.update 23 (Some(n)) m.(0), ())
+
+let rm (m : storage_) : storage_ =
+    (Map.remove 42 m.(0), ())
+
+let gf (m : storage_) : int = Map.find 23 m.(0)
+
+let get (m: storage_): int option =
+    Map.find_opt 42 m.(0)
\ No newline at end of file
diff --git a/src/test/contracts/map.ligo b/src/test/contracts/map.ligo
index dd6770077..7d843f163 100644
--- a/src/test/contracts/map.ligo
+++ b/src/test/contracts/map.ligo
@@ -2,7 +2,16 @@
 
 type foobar is map(int, int)
 
-const fb : foobar = map
+const empty_map : foobar = map end
+
+const map1 : foobar = map
+  144 -> 23 ;
+  51 -> 23 ;
+  42 -> 23 ;
+  120 -> 23 ;
+  421 -> 23 ;
+end
+const map2 : foobar = map
   23 -> 0 ;
   42 -> 0 ;
 end
@@ -31,20 +40,12 @@ function get_ (const m : foobar) : option(int) is
     skip
   end with map_get(42 , m)
 
-const bm : foobar = map
-  144 -> 23 ;
-  51 -> 23 ;
-  42 -> 23 ;
-  120 -> 23 ;
-  421 -> 23 ;
-end
-
-function iter_op (const m : foobar) : int is
-  var r : int := 0 ;
-  function aggregate (const i : int ; const j : int) : unit is block { r := r + i + j } with unit ;
-  block {
-    map_iter(m , aggregate) ;
-  } with r ;
+function iter_op (const m : foobar) : unit is
+  function aggregate (const i : int ; const j : int) : unit is block
+    { if (i=j) then skip else failwith("fail") } with unit ;
+  block {skip}
+    // map_iter(m , aggregate) ;
+  with map_iter(m, aggregate) ;
 
 function map_op (const m : foobar) : foobar is
   function increment (const i : int ; const j : int) : int is block { skip } with j + 1 ;
diff --git a/src/test/contracts/map.mligo b/src/test/contracts/map.mligo
index 375a69507..0d6ec9918 100644
--- a/src/test/contracts/map.mligo
+++ b/src/test/contracts/map.mligo
@@ -1,7 +1,31 @@
 type foobar = (int , int) map
 
-let foobar : foobar = Map.empty
+let empty_map : foobar = Map.empty
 
-let foobarz : foobar = Map.literal [ (1 , 10) ; (2 , 20) ]
+let map1 : foobar = Map.literal
+  [ (144 , 23) ; (51 , 23) ; (42 , 23) ; (120 , 23) ; (421 , 23) ]
+let map2 : foobar = Map [ (23 , 0) ; (42 , 0) ]
 
-let foo : int = Map.find 1 foobarz
+let set_ (n : int) (m : foobar) : foobar =
+    Map.update 23 (Some n) m
+
+let rm (m : foobar) : foobar = Map.remove 42 m
+
+let size_ (m : foobar) : nat = Map.size m
+
+let gf (m : foobar) : int = Map.find 23 m
+
+let get (m : foobar) : int option = Map.find_opt 42 m
+let get_ (m : foobar) : int option = Map.find_opt 42 m
+
+let iter_op (m : foobar) : unit =
+    let assert_eq = fun (i : int) (j : int) -> assert(i=j) in
+    Map.iter m assert_eq
+
+let map_op (m : foobar) : foobar =
+    let increment = fun (i : int) (j : int) -> j+1 in
+    Map.map m increment
+
+let fold_op (m : foobar) : foobar =
+    let aggregate = fun (i : int) (j : (int * int)) -> i + j.(0) + j.(1) in
+    Map.fold m 10 aggregate
\ No newline at end of file
diff --git a/src/test/integration_tests.ml b/src/test/integration_tests.ml
index 2961a5979..fbc966747 100644
--- a/src/test/integration_tests.ml
+++ b/src/test/integration_tests.ml
@@ -377,36 +377,13 @@ let moption () : unit result =
   in
   ok ()
 
-let mmap () : unit result =
-  let%bind program = mtype_file "./contracts/map.mligo" in
-  let%bind () = expect_eq_evaluate program "foobar"
-      (e_annotation (e_map []) (t_map t_int t_int)) in
-  let%bind () = expect_eq_evaluate program "foobarz"
-      (e_annotation (e_map [(e_int 1 , e_int 10) ; (e_int 2 , e_int 20)]) (t_map t_int t_int)) in
-  let%bind () = expect_eq_evaluate program "foo" (e_int 10) in
-  ok ()
-
-let map () : unit result =
-  let%bind program = type_file "./contracts/map.ligo" in
+let map_ type_f path : unit result =
+  let%bind program = type_f path in
   let ez lst =
     let open Ast_simplified.Combinators in
     let lst' = List.map (fun (x, y) -> e_int x, e_int y) lst in
     e_typed_map lst' t_int t_int
   in
-  let%bind () =
-    let make_input = fun n -> ez [(23, n) ; (42, 4)] in
-    let make_expected = e_int in
-    expect_eq_n program "gf" make_input make_expected
-  in
-  let%bind () =
-    let make_input = fun n -> ez List.(map (fun x -> (x, x)) @@ range n) in
-    let make_expected = e_nat in
-    expect_eq_n_strict_pos_small program "size_" make_input make_expected
-  in
-  let%bind () =
-    let expected = ez [(23, 0) ; (42, 0)] in
-    expect_eq_evaluate program "fb" expected
-  in
   let%bind () =
     let make_input = fun n ->
       let m = ez [(23 , 0) ; (42 , 0)] in
@@ -415,6 +392,21 @@ let map () : unit result =
     let make_expected = fun n -> ez [(23 , n) ; (42 , 0)] in
     expect_eq_n_pos_small program "set_" make_input make_expected
   in
+  let%bind () =
+    let input = ez [(23, 23) ; (42, 42)] in
+    let expected = ez [23, 23] in
+    expect_eq program "rm" input expected
+  in
+  let%bind () =
+    let make_input = fun n -> ez List.(map (fun x -> (x, x)) @@ range n) in
+    let make_expected = e_nat in
+    expect_eq_n_strict_pos_small program "size_" make_input make_expected
+  in
+  let%bind () =
+    let make_input = fun n -> ez [(23, n) ; (42, 4)] in
+    let make_expected = e_int in
+    expect_eq_n program "gf" make_input make_expected
+  in
   let%bind () =
     let make_input = fun n -> ez [(23, n) ; (42, 4)] in
     let make_expected = fun _ -> e_some @@ e_int 4 in
@@ -425,34 +417,35 @@ let map () : unit result =
     let make_expected = fun _ -> e_some @@ e_int 4 in
     expect_eq_n program "get_" make_input make_expected
   in
+  let%bind () = expect_eq_evaluate program "empty_map"
+    (e_annotation (e_map []) (t_map t_int t_int)) in
   let%bind () =
     let expected = ez @@ List.map (fun x -> (x, 23)) [144 ; 51 ; 42 ; 120 ; 421] in
-    expect_eq_evaluate program "bm" expected
+    expect_eq_evaluate program "map1" expected
   in
   let%bind () =
-    let input = ez [(23, 23) ; (42, 42)] in
-    let expected = ez [23, 23] in
-    expect_eq program "rm" input expected
+    let expected = ez [(23, 0) ; (42, 0)] in
+    expect_eq_evaluate program "map2" expected
   in
   let%bind () =
-    let input = ez [(1 , 10) ; (2 , 20) ; (3 , 30) ] in
-    let expected = e_int 66 in
+    let input = ez [(1 , 1) ; (2 , 2) ; (3 , 3) ] in
+    let expected = e_unit () in
     expect_eq program "iter_op" input expected
   in
-  let%bind () =
-    let input = ez [(1 , 10) ; (2 , 20) ; (3 , 30) ] in
-    let expected = e_int 76 in
-    expect_eq program "fold_op" input expected
-  in
   let%bind () =
     let input = ez [(1 , 10) ; (2 , 20) ; (3 , 30) ] in
     let expected = ez [(1 , 11) ; (2 , 21) ; (3 , 31) ] in
     expect_eq program "map_op" input expected
   in
+  let%bind () =
+    let input = ez [(1 , 10) ; (2 , 20) ; (3 , 30) ] in
+    let expected = e_int 76 in
+    expect_eq program "fold_op" input expected
+  in
   ok ()
 
-let big_map () : unit result =
-  let%bind program = type_file "./contracts/big_map.ligo" in
+let big_map_ type_f path : unit result =
+  let%bind program = type_f path in
   let ez lst =
     let open Ast_simplified.Combinators in
     let lst' = List.map (fun (x, y) -> e_int x, e_int y) lst in
@@ -483,6 +476,13 @@ let big_map () : unit result =
   in
   ok ()
 
+
+let map () : unit result = map_ type_file "./contracts/map.ligo"
+let mmap () : unit result = map_ mtype_file "./contracts/map.mligo"
+let big_map () : unit result = big_map_ type_file "./contracts/big_map.ligo"
+let mbig_map () : unit result = big_map_ mtype_file "./contracts/big_map.mligo"
+
+
 let list () : unit result =
   let%bind program = type_file "./contracts/list.ligo" in
   let ez lst =
@@ -853,6 +853,7 @@ let main = test_suite "Integration (End to End)" [
     test "map" map ;
     test "map (mligo)" mmap ;
     test "big_map" big_map ;
+    test "big_map (mligo)" mbig_map ;
     test "list" list ;
     test "loop" loop ;
     test "matching" matching ;