Choices are an important part of a healthy open source software community. That’s why we’re excited about Yarn, a new package manager that addresses many of the problems with Node’s default package manager, npm. While npm has done a fantastic job creating a large and vibrant JavaScript ecosystem, I want to share why Yarn is an important addition to the Node.js ecosystem, how it will improve your Node.js development experience, and how Heroku has incorporated it into the build process for your Heroku apps.

Yarn Logo

We began testing Yarn almost immediately after it was released, and began fully supporting it on December 16.

About Yarn

Yarn was released in October 2016 and made a big splash...

Heroku bumped its Bundler version to 1.13.7 almost a month ago, and since then we've had a large number of support tickets opened, many a variant of the following:

Your Ruby version is <X>, but your Gemfile specified <Y> 

I wanted to talk about why you might get this error while deploying to Heroku, and what you can do about it, along with some bonus features provided by the new Bundler version.


First off, why are you getting this error? On Heroku in our Ruby Version docs, we mention that you can use a Ruby directive in your Gemfile to specify a version of Ruby. For example if you wanted 2.3.3 then you would need this:

# Gemfile ruby "2.3.3" 

This is still...

As part of our commitment to security and support, we periodically upgrade the stack image, so that we can install updated package versions, address security vulnerabilities, and add new packages to the stack. Recently we had an incident during which some applications running on the Cedar-14 stack image experienced higher than normal rates of segmentation faults and other “hard” crashes for about five hours. Our engineers tracked down the cause of the error to corrupted dyno filesystems caused by a failed stack upgrade. The sequence of events leading up to this failure, and the technical details of the failure, are unique, and worth exploring.


Heroku runs application...

Today we’re happy to announce that the Sydney, Australia region is now generally available for use with Heroku Private Spaces. Sydney joins Virginia, Oregon, Frankfurt, and Tokyo as regions where Private Spaces can be created by any Heroku Enterprise user. Developers can now deploy Heroku apps closer to customers in the Asia-Pacific area to reduce latency and take advantage of the advanced network & trust controls of Spaces to ensure sensitive data stays protected.


To create a Private Space in Sydney, select the Spaces tab in Heroku Dashboard in Heroku Enterprise, then click the “New Space” button and choose “Sydney, Australia” from the the Space Region dropdown.

After a...

We’re excited to announce that Heroku Autoscaling is now generally available for apps using web dynos.

We’ve always made it seamless and simple to scale apps on Heroku - just move the slider. But we want to go further, and help you in the face of unexpected demand spikes or intermittent activity. Part of our core mission is delivering a first-class operational experience that provides proactive notifications, guidance, and—where appropriate—automated responses to particular application events. Today we take another big step forward in that mission with the introduction of Autoscaling.

Autoscaling makes it effortless to meet demand by horizontally scaling your web dynos based on what’s...

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