At Heroku, we're always working towards improving operational stability with the services we offer. As we recently launched Apache Kafka on Heroku, we've been increasingly focused on hardening Apache Kafka, as well as our automation around it. This particular improvement in stability concerns Kafka's compacted topics, which we haven't talked about before. Compacted topics are a powerful and important feature of Kafka, and as of 0.9, provide the capabilities supporting a number of important features.

Meet the Bug

The bug we had been seeing is that an internal thread that's used by Kafka to implement compacted topics (which we'll explain more of shortly) can die in...


As we begin 2017, we want to thank you for supporting Heroku. Your creativity and innovation continues to inspire us, and pushed us to deliver even more new products and features in 2016. We especially want to thank everyone who helped us by beta testing, sharing Heroku with others, and providing feedback. Here are the highlights of what became generally available in 2016.

Advancing the Developer Experience

Heroku Pipelines

A new way to structure, manage and visualize continuous delivery.

Heroku Review Apps

Test code at a shareable URL using disposable Heroku apps that spin up with each GitHub pull request.

Free SSL for Apps on Paid Dynos

Get SSL encryption on custom domains for...


The Ruby maintainers continued their annual tradition by gifting us a new Ruby version to celebrate the holiday: Ruby 2.4 is now available and you can try it out on Heroku.

Ruby 2.4 brings some impressive new features and performance improvements to the table, here are a few of the big ones:


During the development of the recently released Heroku SSL feature, a lot of work was carried out to stabilize the system and improve its speed. In this post, I will explain how we managed to improve the speed of our TLS handshakes by 4-5x.

The initial reports of speed issues were sent our way by beta customers who were unhappy about the low level of performance. This was understandable since, after all, we were not greenfielding a solution for which nothing existed, but actively trying to provide an alternative to the SSL Endpoint add-on, which is provided by a dedicated team working on elastic load balancers at AWS. At the same time, another of the worries we had was to figure out how...


Today we are announcing the newest version of the Heroku CLI. We know how much time you spend in the CLI as developers and how much pride you take in being able to get things done quickly. Our new CLI has big improvements in performance as well as enhanced readability for humans and machines.

Tuned for Performance

CLI response time is made up of two parts: the API response time and the performance of the CLI itself, and the latter is where we’ve made big improvements. While a typical Unix user should experience responses that are around half a second faster, the biggest gains are for Windows users, as the new CLI no longer has a Ruby wrapper.

When we measured the time it takes for the...


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