diff --git a/.gitignore b/.gitignore
index b4b23c1..f4827a8 100644
--- a/.gitignore
+++ b/.gitignore
@@ -4,7 +4,7 @@
 *.gcov
 *.gcda
 *.gcno
-binary
+os
 test
 example
-coverage
+deps/
\ No newline at end of file
diff --git a/.travis.yml b/.travis.yml
index 3cb95fa..26add4e 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -1,7 +1,17 @@
 language: c
+
+services:
+  - docker
+
 compiler:
-- clang
-- gcc
-script: make run-test
+  - clang
+  - gcc
+
+before_install:
+  - docker pull abranhe/clib
+  - docker run -it -v $(pwd):/src -w /src abranhe/clib sh -c "clib install"
+
+script: docker run -it -v $(pwd):/src -w /src abranhe/clib sh -c "make run-test"
+
 notifications:
-  email: false
+  email: false
\ No newline at end of file
diff --git a/cli.c b/cli.c
index 5ba6e47..ebf1974 100644
--- a/cli.c
+++ b/cli.c
@@ -7,41 +7,72 @@
 
 #include <stdio.h>
 #include <string.h>
+#include <stdlib.h>
 #include "os.h"
 
-const char*
-show_help() {
- return "\n\
- Wanna know your operating system? - I know right :)\n\n\
- Usage:\n\n\
-   $ os <flag> \n\n\
- Options:\n\n\
-   -v,  --version     output version number\n\
-   -h,  --help        output usage information\n\n\
- Example:\n\n\
-   $ os\n\
-   macOS\n\n";
+/*
+ * os version.
+ */
+
+#define VERSION "1.0.1"
+
+/*
+ * Output usage information.
+ */
+
+void
+usage(void) {
+  fprintf(stderr,
+    "\n  Usage: os [options]"
+    "\n"
+    "\n  Options:"
+    "\n"
+    "\n    -h, --help      output help information"
+    "\n    -v, --version   output os version"
+    "\n"
+    "\n  Examples:"
+    "\n"
+    "\n    $ os"
+    "\n    macOS"
+    "\n"
+    "\n"
+    );
+  exit(1);
 }
 
-/* CLI. */
+/*
+ * Output os version.
+ */
+
+void
+version(void) {
+  printf("%s\n", VERSION);
+  exit(0);
+}
+
+/*
+ * CLI
+ */
+
 int
 main(int argc, char **argv) {
   char *a = argv[1];
 
   if (argc == 2) {
     if (!strcmp(a, "-v") || !strcmp(a, "--version")) {
-      printf("%s", "1.0.0\n");
+      version();
       return 0;
     }
 
     if (!strcmp(a, "-h") || !strcmp(a, "--help")) {
-			printf("%s", show_help());
+			usage();
       return 0;
     }
 	}
 
   if (argc > 1) {
-		fprintf(stderr, "\033[31mSee `--help` for details.\033[0m\n");
+		fprintf(stderr, 
+      "\033[31mSee `--help` for details.\033[0m\n");
     return 1;
   }
 
diff --git a/deps/os.c/os.c b/deps/os.c/os.c
deleted file mode 100644
index eb05963..0000000
--- a/deps/os.c/os.c
+++ /dev/null
@@ -1,26 +0,0 @@
-//
-// os.c
-// Get to know your operating system
-//
-// MIT licensed.
-// Copyright (c) Abraham Hernandez <abraham@abranhe.com>
-//
-
-const char * operating_system()
-{
-    #ifdef _WIN32
-    return "win32";
-    #elif _WIN64
-    return "win64";
-    #elif __unix || __unix__
-    return "unix";
-    #elif __APPLE__ || __MACH__
-    return "macOS";
-    #elif __linux__
-    return "linux";
-    #elif __FreeBSD__
-    return "freeBSD";
-    #else
-    return "other";
-    #endif
-}
diff --git a/deps/os.c/os.h b/deps/os.c/os.h
deleted file mode 100644
index 5908921..0000000
--- a/deps/os.c/os.h
+++ /dev/null
@@ -1,21 +0,0 @@
-#ifndef OS_H
-#define OS_H
-
-//
-// os.h
-//
-// MIT licensed.
-// Copyright (c) Abraham Hernandez <abraham@abranhe.com>
-//
-
-#ifdef __cplusplus
-extern "C" {
-#endif
-
-const char * operating_system(void);
-
-#ifdef __cplusplus
-}
-#endif
-
-#endif // OS_H
diff --git a/deps/os.c/package.json b/deps/os.c/package.json
deleted file mode 100644
index 49cb501..0000000
--- a/deps/os.c/package.json
+++ /dev/null
@@ -1,21 +0,0 @@
-{
-  "name": "os.c",
-  "version": "1.0.2",
-  "description": "Small C library to know your operating system",
-  "license": "MIT",
-  "keywords": [
-    "os",
-    "macos",
-    "linux",
-    "windows",
-    "win32",
-    "win64",
-    "operating-system",
-    "tool"
-  ],
-  "repo": "abranhe/os.c",
-  "src": [
-    "os.h",
-    "os.c"
-  ]
-}
diff --git a/package.json b/package.json
index 0ec95ed..4a848aa 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "os",
-  "version": "1.0.0",
-  "description": "Wanna know your operating system? - I know right :)",
+  "version": "1.0.1",
+  "description": "Wanna know your operating system?",
   "license": "MIT",
   "keywords": [
     "operating-system",
@@ -16,7 +16,7 @@
   ],
   "repo": "abranhe/os",
   "dependencies": {
-    "abranhe/os.c": "1.0.2"
+    "abranhe/os.c": "1.0.3"
   },
   "install": "make install"
 }
diff --git a/readme.md b/readme.md
index fa6cf42..46cee3d 100644
--- a/readme.md
+++ b/readme.md
@@ -40,21 +40,17 @@ $ os --help
 You will get:
 
 ```
-Wanna know your operating system? - I know right :)
+  Usage: os [options]
 
- Usage:
+  Options:
 
-   $ os <flag>
+    -h, --help      output help information
+    -v, --version   output os version
 
- Options:
+  Examples:
 
-   -v,  --version     output version number
-   -h,  --help        output usage information
-
- Example:
-
-   $ os
-   macOS
+    $ os
+    macOS
 ```
 
 ## Related
diff --git a/test.sh b/test.sh
index f94fb56..9a83c39 100644
--- a/test.sh
+++ b/test.sh
@@ -19,11 +19,11 @@ function assert {
 
 describe "Help"
   ./os --help > /dev/null 2>&1
-  assert $? 0
+  assert $? 1
 
 describe "Help: short flag"
   ./os -h > /dev/null 2>&1
-  assert $? 0
+  assert $? 1
 
 describe "Version"
   ./os --version > /dev/null 2>&1
@@ -37,6 +37,14 @@ describe "Execute: more than two arguments"
   ./os foo bar baz > /dev/null 2>&1
   assert $? 1
 
+describe "Execute: no arguments"
+  ./os > /dev/null 2>&1
+  assert $? 0
+
+describe "Execute: one argumet or flag"
+  ./os foo > /dev/null 2>&1
+  assert $? 1
+
 printf "\033[32m\n(✓) Passed $tests assertions without errors\033[0m\n"
 
 exit 0