When I start to create a new app in TypeScript, I tend to use relative import at the beginning. But as the app grows, directory structure becomes deep and complicated. And one day, I notice relative path hell appears like below. import * as dbService from "../../../../services/db"; import * as routes…

When you create a prototype, speed and money is super important. You need to show it to user as soon as possible with low cost. Next.js is one of the popular frontend framework which has static generation and server side rendering with simple lambda api. …

Everyone knows writing tests is super important for software development. It enables us to change codes more speedy with less bugs. When it comes to frontend, React Testing Library is becoming popular because it’s easier to test React hooks compared with enzyme. However, because Material UI (MUI) styled component use…

Implement the Basic AAA testing pattern today! — Everyone knows writing tests is super important for software development. It enables us to change codes more speedy with less bugs. When it comes to frontend, React Testing Library is becoming popular because it’s easier to test React hooks compared with enzyme. However, the way to create tests is completely…

Form validation is one of the most complex topic that many frontend engineers face. Although it’s not super difficult to implement it, it’s difficult to organize validation logics. With Vue, you have two main choices, template based validation with vee-validate or model based validation with vuelidate. Both of them are…

Learn webpack bundle config step by step — With create-react-app, you can properly and super easily setup a React TypeScript project. But what if you predict your application becomes big? You would face many problems. For example, you need multiple entry points, you have some node_modules which need to be transpiled to ES5. In such situation, it’s better…

Creating an IoT service is very exciting. You can visualize and analyze many things around you. One of the difficulty of creating IoT service is creating data stream. Because AWS IoT service is very simple, you can easily setup from AWS console. …

Because of network quality and device miniaturization, IoT has been in the news lately. In addition, major clouds, such as AWS, GCP and Azure provides many functions that enables user to create an IoT service. However, some users do not have enough experience on connection between device and cloud because…