Red Hat Developer's top 10 articles of 2021.

We're taking a quick break from the winter recharge to share our 10 most read articles of 2021. Some of the best developers in the world work for Red Hat, and we're fortunate that many of them contribute to Red Hat Developer. We think this year's top 10 articles showcase the breadth of our contributors' interests and expertise, as well as that of our readers. Without further ado, here are Red Hat Developer's most popular articles of 2021.

1. How to activate your no-cost Red Hat Enterprise Linux subscription

Following the January 2020 announcement of Red Hat's new no-cost Red Hat Enterprise Linux (RHEL) subscription, this article walks you through everything you need to set up a subscription in three easy steps. No wonder Miroslav Suchý's How to activate your no-cost Red Hat Enterprise Linux subscription was our most-read article in 2021!

2. Distributed transaction patterns for microservices compared

Bilgin Ibryam is co-author of the Kubernetes Patterns e-book and a frequent contributor, with over a dozen articles published on Red Hat Developer to date. In Distributed transaction patterns for microservices compared, he discusses the benefits and drawbacks of five distributed transaction patterns and addresses one of the pain points of modernizing monolithic applications into microservices. We expect readers will seek out this article for years to come.

3. Application modernization patterns with Apache Kafka, Debezium, and Kubernetes

Another article in Bilgin's series tackling the challenges of modernizing legacy applications, this one offers both a well-tested pattern (Strangler, used in tandem with Outbox, Sidecar, and Saga) and standardized tools for implementing it. Application modernization patterns with Apache Kafka, Debezium, and Kubernetes is a must-read for developers interested in using Kubernetes and Apache Kafka to create robust systems that evolve over time.

4. Making environment variables accessible in front-end containers

We published many articles in 2021 about developing and deploying applications in containers, but this one stood out for its focus on building containers for single-page JavaScript applications. As author Joel Lord explains, the application's configuration settings will be different depending on where the container runs, and the challenge is how to make those settings accessible in any environment. Making environment variables accessible in front-end containers leaves you with a solution that you can reuse for any of your future JavaScript projects.

5. C# 9 top-level programs and target-typed expressions

Red Hatter and .NET Core developer Tom Deseyn's C# 9 language features series was our most popular series this year. This article, C# 9 top-level programs and target-typed expressions, started it all.

6. C# 9 pattern matching

The second article in the C# 9 series, C# 9 pattern matching introduces changes to pattern matching in C# 9, including updates and support for combining, inverting, and nesting patterns. A breezy read with many code samples for developers adopting C# 9.

7. Why should I choose Quarkus over Spring for my microservices?

Quarkus is one of our most popular topics on Red Hat Developer, and this article by Quarkus and Spring Boot developer Eric Deandrea helps to explain why. Find out why many Spring developers are switching to Quarkus and how to get started using the Kubernetes-native Java platform for your microservices.

Note: If you're ready to make the leap from Spring to Quarkus, see Eric's e-book, Quarkus for Spring Developers, published by Red Hat Developer in August 2021.

8. Shenandoah in OpenJDK 17: Sub-millisecond GC pauses

The Shenandoah OpenJDK garbage collection project was created to reduce garbage collection pause times, and this article concludes a series explaining how the Shenandoah team did it. Shenandoah GC Project Lead Roman Kennke opens with a retrospective of pause time improvements from JDK 12 through 16, then describes how introducing concurrent thread stack processing solved the remaining garbage collection pause-time challenge in JDK 17.

9. Deploy Helm charts with Jenkins CI/CD in Red Hat OpenShift 4

This quick read by Shailendra Kumar Singh gets you started with Helm and Jenkins CI/CD in a step-by-step tutorial. Start with an overview of the Helm package manager for Kubernetes, then create and deploy your first Helm chart and use it to deploy an application using Jenkins CI/CD and Red Hat OpenShift. A simple, practical introduction written for beginners.

10. How to work around Docker's new download rate limit on OpenShift

This article, a response to Docker's new download rate limits for anonymous users, introduced in November 2020, explains how to get around the unwanted toomanyrequests error without upgrading to a paid Docker account. Note that this hack, presented by Joel Lord, is specifically for developers experimenting with a free OpenShift cluster in the Developer Sandbox for Red Hat OpenShift.


We hope you've enjoyed this recap of Red Hat Developer's 10 most read articles and tutorials published in 2021. During the past year, we've had the pleasure of publishing hundreds of technical articles and other resources (such as cheat sheets, interactive courses, and Developer Sandbox activities) written by developers working at Red Hat. See the following for more of our most sought articles and other resources in 2021:

Happy New Year from all of us on the Red Hat Developer editorial team!

Last updated: September 20, 2023