diff --git a/tests/tests.lua b/tests/tests.lua
new file mode 100644
index 0000000..af141e0
--- /dev/null
+++ b/tests/tests.lua
@@ -0,0 +1,281 @@
+-- tests.lua - Комплексные тесты для СУБД futriix
+
+local test_utils = {}
+
+function test_utils.assert(condition, message)
+    if not condition then
+        error("TEST FAILED: " .. (message or "Assertion failed"))
+    end
+end
+
+function test_utils.run_test(test_name, test_func)
+    print("Running test: " .. test_name)
+    local success, result = pcall(test_func)
+    if success then
+        print("✓ " .. test_name .. " - PASSED")
+        return true
+    else
+        print("✗ " .. test_name .. " - FAILED: " .. result)
+        return false
+    end
+end
+
+-- 1. Регрессионный тест
+function regression_test()
+    -- Проверяем, что базовые операции работают корректно
+    create_space("regression_test_space")
+    
+    -- Тест создания документа
+    local test_data = {name = "test", value = 42, tags = {"a", "b", "c"}}
+    insert("regression_test_space", "doc1", json_encode(test_data))
+    
+    -- Тест чтения
+    local result = get("regression_test_space", "doc1")
+    test_utils.assert(result ~= "null", "Document should exist")
+    
+    local parsed = json_decode(result)
+    test_utils.assert(parsed.name == "test", "Name should match")
+    test_utils.assert(parsed.value == 42, "Value should match")
+    
+    -- Тест обновления
+    local update_data = {name = "updated", value = 100, new_field = "added"}
+    update("regression_test_space", "doc1", json_encode(update_data))
+    
+    local updated = json_decode(get("regression_test_space", "doc1"))
+    test_utils.assert(updated.name == "updated", "Name should be updated")
+    test_utils.assert(updated.new_field == "added", "New field should exist")
+    
+    -- Тест удаления
+    delete("regression_test_space", "doc1")
+    local deleted = get("regression_test_space", "doc1")
+    test_utils.assert(deleted == "null", "Document should be deleted")
+    
+    -- Очистка
+    delete_space("regression_test_space")
+    
+    return "Regression test completed successfully"
+end
+
+-- 2. Smoke-тест (проверка работоспособности)
+function smoke_test()
+    -- Проверяем базовую функциональность системы
+    test_utils.assert(pcall(create_space, "smoke_test_space"), "Should create space")
+    test_utils.assert(pcall(delete_space, "smoke_test_space"), "Should delete space")
+    
+    -- Проверяем функции JSON
+    local test_obj = {test = true, number = 123}
+    local encoded = json_encode(test_obj)
+    local decoded = json_decode(encoded)
+    test_utils.assert(decoded.test == true, "JSON encode/decode should work")
+    test_utils.assert(decoded.number == 123, "JSON numbers should work")
+    
+    -- Проверяем MD5
+    local hash = md5("test")
+    test_utils.assert(type(hash) == "string", "MD5 should return string")
+    test_utils.assert(#hash == 32, "MD5 hash should be 32 characters")
+    
+    return "Smoke test passed - system is operational"
+end
+
+-- 3. Unit-тест (тестирование отдельных функций)
+function unit_test_md5()
+    -- Тестируем функцию MD5 хеширования
+    local test_cases = {
+        {"", "d41d8cd98f00b204e9800998ecf8427e"},
+        {"hello", "5d41402abc4b2a76b9719d911017c592"},
+        {"futriix", "3e8c8d2e7e7a6e8f7b6c8a9d0e1f2a3b"} -- пример хеша
+    }
+    
+    for i, case in ipairs(test_cases) do
+        local input, expected = case[1], case[2]
+        local result = md5(input)
+        test_utils.assert(result == expected, 
+            string.format("MD5('%s') should be '%s', got '%s'", input, expected, result))
+    end
+    
+    return "MD5 unit test passed"
+end
+
+function unit_test_json()
+    -- Тестируем JSON функции
+    local complex_obj = {
+        string = "test",
+        number = 42.5,
+        boolean = true,
+        array = {1, 2, 3},
+        nested = {key = "value"}
+    }
+    
+    local encoded = json_encode(complex_obj)
+    local decoded = json_decode(encoded)
+    
+    test_utils.assert(decoded.string == "test", "String should match")
+    test_utils.assert(decoded.number == 42.5, "Number should match")
+    test_utils.assert(decoded.boolean == true, "Boolean should match")
+    test_utils.assert(#decoded.array == 3, "Array length should match")
+    test_utils.assert(decoded.nested.key == "value", "Nested object should match")
+    
+    return "JSON unit test passed"
+end
+
+-- 4. Нагрузочный тест
+function load_test()
+    local space_name = "load_test_space"
+    create_space(space_name)
+    
+    local start_time = os.time()
+    local operations_count = 100  -- Уменьшено для демонстрации
+    
+    -- Тест записи
+    for i = 1, operations_count do
+        local data = {
+            id = i,
+            timestamp = os.time(),
+            data = string.rep("X", 100) -- 100 байт данных
+        }
+        insert(space_name, "key_" .. i, json_encode(data))
+    end
+    
+    -- Тест чтения
+    for i = 1, operations_count do
+        local result = get(space_name, "key_" .. i)
+        test_utils.assert(result ~= "null", "Should read written data")
+    end
+    
+    local end_time = os.time()
+    local duration = end_time - start_time
+    
+    -- Очистка
+    for i = 1, operations_count do
+        delete(space_name, "key_" .. i)
+    end
+    delete_space(space_name)
+    
+    local ops_per_second = operations_count * 2 / duration  -- запись + чтение
+    
+    return string.format("Load test completed: %d operations in %d seconds (%.2f ops/sec)", 
+        operations_count * 2, duration, ops_per_second)
+end
+
+-- 5. Интеграционный тест
+function integration_test()
+    -- Тестируем взаимодействие различных компонентов
+    create_space("users")
+    create_space("profiles")
+    
+    -- Создаем пользователя с профилем
+    local user_data = {
+        username = "testuser",
+        email = "test@example.com",
+        password = md5("password123"),
+        created_at = os.date()
+    }
+    
+    local profile_data = {
+        user_id = "testuser",
+        full_name = "Test User",
+        preferences = {theme = "dark", notifications = true}
+    }
+    
+    insert("users", "testuser", json_encode(user_data))
+    insert("profiles", "testuser_profile", json_encode(profile_data))
+    
+    -- Проверяем связность данных
+    local user = json_decode(get("users", "testuser"))
+    local profile = json_decode(get("profiles", "testuser_profile"))
+    
+    test_utils.assert(user.username == profile.user_id, "User ID should match")
+    test_utils.assert(user.password == md5("password123"), "Password should be hashed")
+    
+    -- Тестируем транзакционность (имитация)
+    local tx_id = "test_tx_" .. os.time()
+    begin_transaction(tx_id)
+    
+    -- В реальной системе здесь были бы операции в транзакции
+    print("Transaction started: " .. tx_id)
+    
+    -- Очистка
+    delete("users", "testuser")
+    delete("profiles", "testuser_profile")
+    delete_space("users")
+    delete_space("profiles")
+    
+    return "Integration test passed - components work together correctly"
+end
+
+-- 6. API тест
+function api_test()
+    -- Тестируем API-подобные операции через быстрые команды
+    -- (это имитация HTTP API вызовов)
+    
+    create_space("api_test_space")
+    
+    -- Имитация POST /document/space/key
+    local post_data = {action = "create", data = {test = "value"}}
+    insert("api_test_space", "api_doc", json_encode(post_data))
+    
+    -- Имитация GET /document/space/key  
+    local get_result = get("api_test_space", "api_doc")
+    test_utils.assert(get_result ~= "null", "API should retrieve document")
+    
+    local parsed_get = json_decode(get_result)
+    test_utils.assert(parsed_get.action == "create", "API data should match")
+    
+    -- Имитация PUT /document/space/key
+    local put_data = {action = "update", data = {test = "new_value"}}
+    update("api_test_space", "api_doc", json_encode(put_data))
+    
+    local updated = json_decode(get("api_test_space", "api_doc"))
+    test_utils.assert(updated.action == "update", "API update should work")
+    
+    -- Имитация DELETE /document/space/key
+    delete("api_test_space", "api_doc")
+    test_utils.assert(get("api_test_space", "api_doc") == "null", "API delete should work")
+    
+    delete_space("api_test_space")
+    
+    return "API test passed - all HTTP verb simulations work correctly"
+end
+
+-- Главная функция запуска всех тестов
+function run_all_tests()
+    print("=== Running futriix Database Tests ===\n")
+    
+    local tests = {
+        {"Smoke Test", smoke_test},
+        {"Unit Test - MD5", unit_test_md5},
+        {"Unit Test - JSON", unit_test_json},
+        {"Regression Test", regression_test},
+        {"Integration Test", integration_test},
+        {"API Test", api_test},
+        {"Load Test", load_test}
+    }
+    
+    local passed = 0
+    local total = #tests
+    
+    for _, test_info in ipairs(tests) do
+        local test_name, test_func = test_info[1], test_info[2]
+        if test_utils.run_test(test_name, test_func) then
+            passed = passed + 1
+        end
+        print()
+    end
+    
+    print(string.format("=== Test Results: %d/%d passed ===", passed, total))
+    
+    if passed == total then
+        print(" ALL TESTS PASSED! ")
+        return true
+    else
+        print("❌ SOME TESTS FAILED")
+        return false
+    end
+end
+
+-- Запуск тестов при прямом выполнении файла
+if arg and arg[0] and string.match(arg[0], "tests.lua") then
+    run_all_tests()
+else
+    print("futriix test library loaded. Call 'run_all_tests()' to execute tests.")
+end