Toptal Engineering Blog

The Toptal Engineering Blog is a hub for in-depth development tutorials and new technology announcements created by professional software engineers in the Toptal network.

authors are vetted experts in their fields and write on topics in which they have demonstrated experience. All of our content is peer reviewed and validated by Toptal experts in the same field.

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authors are vetted experts in their fields and write on topics in which they have demonstrated experience. All of our content is peer reviewed and validated by Toptal experts in the same field.

Accelerate With BERT: NLP Optimization Models

Data collection and preparation slow down traditional NLP projects. However, transfer learning and BERT can reduce the amount of data required and change the way companies execute NLP projects.

6 minute readContinue Reading

Jesse Moore

Jesse is a chief data scientist, CTO, and founder who has launched four companies, including an NLP news-parsing solution that was acquired in 2018. He has consulted at top technology companies like Zalando and MariaDB and is currently the head of data science at THINKAlpha.

Build with Confidence: A Guide to JUnit Tests

In an age of continuous delivery, Java developers have to be confident that their changes don’t break existing code, hence automated testing. There’s more than one valid approach to it, but how can you keep them straight?

11 minute readContinue Reading

Nikhil Bansal

Nikhil (BTech) has automated finance sector code across everything from J2EE to Elasticsearch to Kafka. And, of course, all things AWS.

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How to Build a Role-based API with Firebase Authentication

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 role-based authentication, we’ll learn how to implement this system in an API using Node.js and Firebase.

15 minute readContinue Reading

Joaquin Cid

Joaquin is a full-stack developer with over 12 years of experience working for companies like WebMD and Getty Images.

Make Your App Profitable, Part 2 – Harnessing the Mobile Funnel

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.

10 minute readContinue Reading

Matthew Knippen

Having built 60+ iOS apps since 2008 using Swift and Objective-C, Matthew is most known for going from idea to App Store within eight weeks.

Creating Your First GraphQL API

GraphQL is a domain-specific language for data query and manipulation by Facebook. It is meant to replace the de facto REST standard in API creation.

In this article, Toptal Freelance GraphQL Developer Ioram Gordadze creates a GraphQL API from scratch, summarizing problems new GraphQL developers face. He also teaches us to rethink the standard methods used in REST APIs in a more GraphQL-friendly manner.

16 minute readContinue Reading

Ioram Gordadze

Ioram has designed and developed databases, API services, and more for both private and government organizations.

Increase Code Maintainability With React Integration Testing

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.

7 minute readContinue Reading

Anton Rublev

Anton is a full-stack developer with a strong technical background. He specializes in JavaScript and he’s a fan of test-driven development.

Avoiding Bad Practices in iOS and Android Design

In an era of cross-platform mobile development, it is crucial to understand the specifics of different operating systems and hardware.

In this article, Mobile Developer Martin Doychev lists a number of bad practices employed while creating apps for iOS and Android and explains what you should and shouldn’t do.

9 minute readContinue Reading

Martin Doychev

Martin is a mobile developer and teacher, with ample experience in many languages and frameworks. As of late, he is focused on React Native.

Toptal Engineering Expert

Gabriel Courtemanche

Gabriel is a highly efficient and reliable professional who possesses a broad skill set for web application development. He's been working on a range of products and clients—from working on scalability problems in production engineering teams at Shopify and Autodesk to launching new applications for startups. Most of his work consists of leading technical teams, by creating an easy development environment, fixing technical debts, providing best practices code examples, and mentoring devs.