Important update

We've recently made some big updates to our support for Docker and the feature described in this blog post has been deprecated. Learn more in the container registry and runtime dev center documentation.


When Heroku launched the Cedar container stack 4 years ago, we became one of the first companies to use Linux Containers (LXC) to create a secure, performant and scalable cloud platform. Heroku has been a leader in the containerization movement, and we’ve spent years hardening, honing and evolving our runtime container stack. This means that developers can git push apps written in their favorite language and Heroku will build containers that are deployed to a...


At Heroku and at Salesforce, we’re always looking for ways we can help increase the number of young women with access to careers in science, technology, engineering and math. Recently, thanks to a Heroku engineering manager’s involvement on this issue with a local school, we hosted a Technovation Challenge event at the Heroku offices. We wanted to share the story about this great program - the Technovation Challenge is an annual competition, and you could do something similar in your community!

Some background

For the past 3 years, Heroku engineering manager Margaret Le has mentored a group of high school girls at the Immaculate Conception Academy (ICA), a San Francisco high school...


Today we’re excited to announce public beta support for HTTP session affinity, a feature that makes building real-time applications easier than ever. Session affinity improves end user experience in certain types of applications and architectures where you require some level of extra state within your application code, because it ensures related requests get routed to the same instance of your code. This improves performance reducing the need to go and get the needed state for a specific user.

At high level, here's how it works: When you enable session affinity on your application, the Heroku router will set a special cookie on every HTTP request. This cookie will allow our routing...


We’re pleased to announce PostgreSQL 9.4 in general availability for Heroku Postgres. After announcing the beta earlier this year, we’ve had many developers provision databases against this new version. Throughout the beta period, developers raved about the new data type along with the performance enhancements to materialized views. This uptake by early adopters demonstrates an interest in everything that the new version of PostgreSQL provides, from features to performance.

New Features and Performance Updates

One of the most notable new features of 9.4 is the JSONB data type. While the text-based JSON data type has existed in PostgreSQL for some time, JSONB is a binary storage format...


These days, apps are more composed than built. Long past are the days of spinning up your own Elasticsearch cluster to add search to your application. Instead we borrow from previous projects, and adapt a template as a good foundation. It’s a great improvement – but the process of keeping up to date with the right services, tools, and templates can be a time consuming task at best, and an overwhelming flood of new information at worst.

Today we're excited to announce Heroku Elements, a new marketplace that brings all of the pieces within our Heroku ecosystem together in one place. It’s a simpler way to discover and select the best components to build apps fast.

In a nutshell, Heroku...


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