Technology

Nearly every app requires an authorization system on top of an authentication system. We often need a fine-grained permissions model to allow only specific users to access certain resources while simultaneously restricting access for everyone else. In this tutorial, Toptal Freelance Firebase Developer Joaquin Cid teaches how to build just such a system. Called a role-based authentication, we’ll learn how to implement this system in an API using Node.js and Firebase.

Subscription-based apps need a special approach when it comes to analytics. Learn how a variation on the traditional sales funnel helps you work with LTV, subscriber retention, and churn rates to make your app better—and more profitable.

Integration tests provide a lot of value considering the time and effort required for testing. React integration tests improve code maintainability, yet they don’t slow down development. In this article, Toptal Software Developer Anton Rublev demonstrates how you can harness the power of react-testing-library to create superior code without wasting time.

Radio has used fundamentally the same technology since Marconi’s experiments in 1895. However, improved circuit design and signal processing techniques have allowed us to transmit much more and much farther out than before. In this article, with a laptop and less than $30 worth of equipment, we’ll capture images transmitted from the International Space Station and listen to amateur radio conversations at a local repeater.

Five years after Dart 1.0, Google's rewritten open-source language is attracting increasing numbers of developers. What do C# and Java developers need to know to get started with it?

WordPress code, especially back-end PHP code, is often a mess—even in WP core! But legacy code is no excuse. Find out how to develop WP customizations the right way, so your code is readable and maintainable.

The ELK stack boasts a range of impressive capabilities, but in some scenarios, it can be difficult to configure and maintain. In this article, Toptal DevOps Engineer Fabrice Triboix explains why he decided to shift to a serverless solution that requires less maintenance and allows for superior scaling.

Are Vue.js, React, and Angular actually delivering a good developer and user experience, or are they used simply because they're the current de facto standard? Discover some exciting approaches to web development.