diff --git a/lib/ansi.mligo b/lib/ansi.mligo
new file mode 100644
index 0000000..1b23905
--- /dev/null
+++ b/lib/ansi.mligo
@@ -0,0 +1,29 @@
+(* MIT License
+
+   Copyright (c) 2022 Marigold <contact@marigold.dev>
+
+   Permission is hereby granted, free of charge, to any person obtaining a copy
+   of this software and associated documentation files (the "Software"), to deal in
+   the Software without restriction, including without limitation the rights to
+   use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
+   the Software, and to permit persons to whom the Software is furnished to do so,
+   subject to the following conditions:
+
+   The above copyright notice and this permission notice shall be included in all
+   copies or substantial portions of the Software.
+
+   THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+   IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+   FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+   AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+   LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+   OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+   SOFTWARE. *)
+
+let top = Option.unopt (Test.chr 27n)
+
+let green message =
+  top ^ "[32m" ^ message ^ top ^ "[0m"
+
+let red message =
+  top ^ "[31m" ^ message ^ top ^ "[0m"
\ No newline at end of file
diff --git a/lib/model.mligo b/lib/model.mligo
index bfa8818..f8ec75b 100644
--- a/lib/model.mligo
+++ b/lib/model.mligo
@@ -23,6 +23,7 @@
 #import "util.mligo" "Util"
 #import "logger.mligo" "Logger"
 #import "result.mligo" "Result"
+#import "ansi.mligo" "Ansi"
 
 (** Describes the model of the test engine. *)
 
@@ -63,10 +64,12 @@ let perform_case (log_level: Logger.level) (case : case) : (bool * string) =
 
 (** Pretty print the result of a test. *)
 let pp_case_result (is_succeed : bool) (message : string) (case : case) =
-  let flag = if is_succeed then "[v]" else "[x]" in
+  let flag, color = if is_succeed then "v", Ansi.green else "x", Ansi.red in
   let full_message =
-    flag ^ " " ^ case.case_name ^ " | " ^ case.case_desc
-    ^ ":\n    " ^ message
+    "[" ^ (color flag) ^ "]" 
+    ^ case.case_name ^ " | " 
+    ^ case.case_desc ^ ":\n    " 
+    ^ color message
   in
   Test.println full_message
 
@@ -93,10 +96,12 @@ let run_suite (log_level: Logger.level) (suite: suite) : bool =
  let is_succeed = failed_test = 0n in
  let () =
    if not is_succeed then
-     Test.println
-        ("There is some tests ("
+     let message = 
+        "There is some tests ("
         ^ Util.nat_to_string_without_suffix failed_test
-        ^ ") that fails")
+        ^ ") that fails"
+     in Test.println (Ansi.red message)
+        
  in
  is_succeed