Toptal Engineering Blog

Your software isn’t fully tested until you write integration tests for it. While unit tests help ensure that functions are properly written, integration tests help ensure that the system is working properly as a whole.

In this article, Toptal Software Engineer Luka Blažecki uses Node.js to explain why integration testing is important for every development platform and how to write clean, composable integration tests.

WordPress plugins can be both a blessing and a curse. With more than 45,000 plugins available in its official repository, WordPress users can customize their website to their heart’s content. However, not all plugins follow the standards necessary to keep the platform performant and secure while also delivering a solid user experience.

In this tutorial, Toptal Software Engineer Ratko Solaja shows us how to build a robust WordPress plugin, following all the necessary best practices.

In the past few years, Microsoft has pulled a few aces from up its sleeve. Yes, they messed up Skype, failed with smartphones, and almost succeeded with tablets. But, they did some really amazing things as well.

Relinquishing their closed empire approach, they open-sourced .NET, joined the Linux Foundation, released SQL Server for Linux, and created this great new tool called Visual Studio for Mac.

In this post, Head of Open Source Demir Selmanovic details how to make an Android and iOS app in C# on your Mac.

Limited SQL scalability has prompted the industry to develop and deploy a number of NoSQL database management systems, with a focus on performance, reliability, and consistency. The trend was driven by proprietary NoSQL databases developed by Google and Amazon. Eventually, open-source systems like MongoDB, Cassandra, and Hypertable brought NoSQL within reach of everyone.

In this post, Toptal Software Engineer Mohamad Altarade dives into some of them and explains why NoSQL will probably be with us for years to come.

WordPress, one of the most popular publishing platforms, has stood the test of time and now powers a significant portion of the web. Sadly, its reputation is plagued by claims of poor performance and complexity with scaling. However, the root causes of such performance issues are often bad code and poorly implemented plugins and themes.

In this post, Toptal Software Engineer Martín Di Felice shares tips and tricks for WordPress developers who want to build better plugins and themes and destroy the notion that WordPress is a slow platform.

Your website is gaining traction, and you are growing rapidly. Ruby/Rails is your programming language of choice. Your team is bigger and you’ve given up on “fat models, skinny controllers” as a design style for your Rails apps. However, you still don’t want to abandon using Rails? No problem.

In this article, Toptal Software Engineer Eqbal Quran explains how you can decouple and isolate your Rails components using nothing Plain Old Ruby Objects. Ruby objects and abstractions can decouple concerns, simplify testing, and help you produce clean, maintainable code.

You’ve heard that Magento is the eCommerce platform to use if you’re serious about your business – and you’re serious about your business – so you’ve decided on Magento. But do you know what you’re getting into?

In this post, Toptal Software Engineer Andrew Hughes walks us through the difference between WordPress WooCommerce and Magento. While Magento is the expert’s eCommerce platform of choice, it’s not always the right solution, depending on your client.

With the rise of big data and data science, storage and retrieval have become a critical pipeline component for data use and analysis. Recently, new data storage technologies have emerged. But the question is: Which one should you choose? Which one is best suited for data engineering?

In this article, Toptal Data Scientist Ken Hu compares three prominent storage technologies within the context of data engineering.

Most modern programming languages, in the hopes of enhanced maintainability and reusability of code, offer some constructs that help the developer keep the definition of behavior and its implementation separate.

Swift takes the idea of interfaces a step further with protocols. With protocols and protocol extensions, Swift allows developers to enforce elaborate conformity rules without compromising the expressiveness of the language.

In this article, Toptal Software Engineer Alexander Gaidukov explores Swift protocols and how protocol-oriented programming can improve the maintainability and reusability of your code.

Let’s face it: Sometimes you just need to rant. Fortunately, there’s an app for that. It’s called devRant, and it’s the place for developers to vent about clients from hell, non-technical friends and family, and clueless recruiters.

In this roundup, devRant Co-Founder David Fox shares his favorite collection of rants since launching. Some will make you laugh. Others will make you laugh so hard you cry. And just about all of them will make you empathize with the author.

If you’re a veteran frontender, you’ve probably had some not-so-great experiences with designers, and chances are some designers have had an equally bad experience working with you. How can you make sure you get exactly what you need from your designer, without placing an undue burden on them?

It’s a tall order, but in this article Freelance Software Engineer Vedran Aberle Tokic outlines and addresses a number of potential issues that may become roadblocks for your execution. Implementing these suggestions may result in overhead for designers, but they can save enormous amounts of time and headache elsewhere.

Nobody wants to leave valuable customer data behind. Unfortunately, though, the hardest part of data migration to a complex CRM system, such as Salesforce, is the handling of legacy data.

In this article, Toptal Software Engineer Marian Paul provides 10 tips for successful legacy data migration to Salesforce.

Client-server interactions play a vital role in most modern mobile applications. By leveraging available backend services these mobile applications can provide some really amazing functionalities. However, as mobile applications grow complex it becomes essential to keep the networking module as clean and maintainable as possible - separated from the rest of the application logic.

In this article, Toptal freelance software engineer Alexander Gaidukov walks us through the design of a simple networking module that allows your iOS application to interact with RESTful APIs.

The Hadoop Distributed File System (HDFS) is a scalable, open source solution for storing and processing large volumes of data. With its built-in replication and resilience to disk failures, HDFS is an ideal system for storing and processing data for analytics.

In this step-by-step tutorial, Toptal Database Developer Dallas H. Snider details how to migrate existing data from a PostgreSQL database into the more efficient HDFS.

Genome data is one of the most widely analyzed datasets in the realm of Bioinformatics. The SciPy stack offers a suite of popular Python packages designed for numerical computing, data transformation, analysis and visualization, which is ideal for many bioinformatic analysis needs.

In this tutorial, Toptal Software Engineer Zhuyi Xue walks us through some of the capabilities of the SciPy stack. He also answers some interesting questions about the human genome, including: How much of the genome is incomplete? How long is a typical gene?

Swift is the new programming language created to be a modern replacement for Objective-C in iOS and OS X application development. In general, a skilled Swift developer is usually someone who is already experienced with Objective-C, and that, among other things, might lead them to write Swift code using Objective-C best practices, which can cause some bad mistakes.

In this article, Toptal Freelance Software Engineer Nilson Souto outlines the most common mistakes Swift developers should be aware of.

Any experienced developer will tell you that their best code isn’t code they wrote. It’s code they took from someone else’s work. Many of the problems we encounter have already been solved—and the remedies packaged into libraries available to anyone. Why reinvent the wheel when free wheels are everywhere?

In this guide, Senior Android Engineer Gilad Haimov will take you on a quick tour of some the most powerful Android libraries out there. Robust as a hammer, faster than a drill, and more precise than any scalpel; no Android developer should leave home without these must-have tools.

Google formally announced Android 7.0 a few weeks ago, but as usual, you’ll have to wait for it. Thanks to the Android update model, most users won’t get their Android 7.0 over-the-air (OTA) updates for months. However, this does not mean developers can afford to ignore Android Nougat.

In this article, Toptal Technical Editor Nermin Hajdarbegovic takes a closer look at Android 7.0, outlining new features and changes. While Android 7.0 is by no means revolutionary, the introduction of a new graphics API, a new JIT compiler, and a range of UI and performance tweaks will undoubtedly unlock more potential and generate a few new possibilities.

Apple’s iOS is the second-largest mobile operating system in the world. It also has a very high adoption rate, with more than 85 percent of users on the latest version. These highly engaged users have high expectations: If your app has bugs, you’ll hear about it. And once the one-star reviews start rolling in, it’s hard to recover.

In this article, Toptal Software Engineer Nikita Tuk outlines the 10 most common mistakes that developers make—and how to avoid them.

Gone are the days where front-end developers for web applications could use ad-hoc JavaScript with jQuery and such all in a single JavaScript file. Modern web applications require more effort from the developer to adopt an overall architecture and development process. Building such front-end applications relies on lots of external dependencies and modular source code, and these elements necessitate automation to save developers time and reduce the chances of mistakes.

In this article, Toptal Freelance Software Engineer Eric Grosse shows us how various combinations of the popular tools Webpack, Browserify, Gulp and Npm can benefit us by enhancing our development environment and allowing us to focus on writing the app itself.

Caching is a powerful technique for increasing performance, but the whole idea behind caching works only as long as the result we cached remains valid. And here we get to the hard part of the problem: How do we determine when a cached item has become invalid and needs to be recreated?

In this article, Toptal Freelance Software Engineer Daniel Ivanov provides an ASP.NET-based solution to replace invalid cached items and assure high throughput and performance of web applications designed to handle a high load.