Category: JavaScript

JavaScript Testing

Introduction to performance testing with k6

Writing unit and integration tests is a great way to verify the business logic in our code. Unfortunately, it might not be enough to ensure that our application works as expected in a real-life scenario. When hundreds, thousands, or millions of users use our API, it strains it. We simulate the above circumstances through performance […]


Rendering long lists using virtualization with React

When working on web applications, we often display lists of data. If the data is not particularly lengthy, we are probably okay with rendering all elements at once. However, as our data grows, we might notice performance issues. In this article, we create a simple React application that aims to render thousands of images using […]

JavaScript NestJS

API with NestJS #62. Introduction to MikroORM with PostgreSQL

This entry is part 62 of 77 in the API with NestJS

So far, in this series, we’ve used a few different solutions for managing databases. To work with MongoDB, we’ve used Mongoose. To manage a PostgreSQL database, we’ve utilized TypeORM and Prisma. This article looks into another Object-relational mapping (ORM) library called MikroORM. By having a broad perspective on what’s available, we can choose the library […]


Dynamic and recursive forms with Formik and TypeScript

Formik is a popular tool that helps us write React forms and keep their code consistent across even big projects. Besides having a fixed number of properties, we sometimes need to allow the user to shape the form to some extent and create recursive data structures. In this article, we learn how to do that […]

JavaScript React

Using AbortController to deal with race conditions in React

When developing applications, data fetching is one of the most fundamental tasks. Despite that, there are some things to watch out for: one of them is race conditions. This article explains what they are and provides a solution using the AbortController. Identifying a race condition A “race condition” is when our application depends on a […]