diff --git a/CMakeLists.txt b/CMakeLists.txt
index 9ec292f..14d92c5 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -5,8 +5,11 @@ set(CMAKE_MODULE_PATH ${CMAKE_SOURCE_DIR}/cmake/modules)
 find_package(Neon REQUIRED)
 find_package(JsonC REQUIRED)
 
-add_library(yadisk src/yandex_disk_api.c
-        tests/ctest.c)
+add_library(yadisk src/yandex_disk_api.c)
+add_executable(test-app tests/app.c)
 
 target_include_directories(yadisk PRIVATE ${NEON_INCLUDE_DIR} ${JSON_C_INCLUDE_DIR})
-target_link_libraries(yadisk ${NEON_LIBRARIES} ${JSON_C_LIBRARIES})
\ No newline at end of file
+target_link_libraries(yadisk ${NEON_LIBRARIES} ${JSON_C_LIBRARIES})
+
+target_include_directories(test-app PRIVATE "${CMAKE_SOURCE_DIR}/src" ${NEON_INCLUDE_DIR} ${JSON_C_INCLUDE_DIR})
+target_link_libraries(test-app yadisk)
\ No newline at end of file
diff --git a/src/yandex_disk_api.c b/src/yandex_disk_api.c
index b94d92e..5e982ac 100644
--- a/src/yandex_disk_api.c
+++ b/src/yandex_disk_api.c
@@ -17,21 +17,23 @@ static int api_http_request(
 
 void yadisk_get_disk(yadisk_api_client *client, yadisk_disk_info* info) {
     char* output = NULL;
-    int result = api_http_request(client, "GET", "/v1/disk", &output);
+    int error = api_http_request(client, "GET", "/v1/disk", &output);
     json_object* root = json_tokener_parse(output);
-    free(output);
 
-    if (!result) {
+    if (error) {
         json_object_put(root);
         return;
     }
 
     json_object* total_space = NULL;
-    json_object_object_get_ex(root, "total_space", &total_space);
-    info->total_space = json_object_get_int64(total_space);
+    if (!json_object_object_get_ex(root, "total_space", &total_space)) {
+        printf("Key total_space doesn't exists!");
+    }
+    info->total_space = json_object_get_uint64(total_space);
     json_object_put(total_space);
 
     json_object_put(root);
+    free(output);
 }
 
 void yadisk_delete_disk_resources(yadisk_api_client *client) {
diff --git a/src/yandex_disk_api.h b/src/yandex_disk_api.h
index 12bf5c8..add9624 100644
--- a/src/yandex_disk_api.h
+++ b/src/yandex_disk_api.h
@@ -17,7 +17,7 @@ typedef struct yadisk_api_client
 
 typedef struct yadisk_disk_info
 {
-    long total_space;
+    unsigned long total_space;
 } yadisk_disk_info;
 
 void yadisk_get_disk(yadisk_api_client* client, yadisk_disk_info* info);
diff --git a/tests/app.c b/tests/app.c
new file mode 100644
index 0000000..034695b
--- /dev/null
+++ b/tests/app.c
@@ -0,0 +1,25 @@
+//
+// Created by maxim on 27.11.23.
+//
+
+#include <yandex_disk_api.h>
+#include <stdio.h>
+
+int main() {
+    char token[1024];
+
+    printf("Enter OAuth token: ");
+    fgets(token, sizeof(token), stdin);
+
+    yadisk_api_client* client = &(yadisk_api_client){
+            .token = token
+    };
+
+    yadisk_disk_info yadisk_disk_info;
+
+    yadisk_get_disk(client, &yadisk_disk_info);
+
+    printf("Total disk size: %lu", yadisk_disk_info.total_space);
+
+    return 0;
+}
\ No newline at end of file