There are always challenges when it comes to debugging applications. Node.js' asynchronous workflows add an extra layer of complexity to this arduous process. Although there have been some updates made to the V8 engine in order to easily access asynchronous stack traces, most of the time, we just get errors on the main thread of our applications, which makes debugging a little bit difficult. As well, when our Node.js applications crash, we usually need to rely on some complicated CLI tooling to analyze the core dumps.


YAML files dominate configuration in the cloud native ecosystem. They’re used by Kuberentes, Helm, Tekton, and many other projects to define custom configuration and workflows. But YAML has its oddities, which is why the Cloud Native Buildpacks project chose TOML as its primary configuration format.

TOML is a minimal configuration file format that's easy to read because of its simple semantics. You can learn more about TOML from the official documentation, but a simple buildpack TOML file looks like this:


I work on Heroku’s Runtime Infrastructure team, which focuses on most of the underlying compute and containerization here at Heroku. Over the years, we’ve tuned our infrastructure in a number of ways to improve performance of customer dynos and harden security.

We recently received a support ticket from a customer inquiring about poor performance in two system calls (more commonly referred to as syscalls) their application was making frequently: clock_gettime(3) and gettimeofday(2).

In this customer’s case, they were using a tool to do transaction tracing to monitor the performance of their application. This tool made many such system calls to measure how long different parts of their...


When API requests are made one-after-the-other they'll quickly hit rate limits and when that happens:

That tweet spawned a discussion that generated a quest to add rate throttling logic to the platform-api gem that Heroku maintains for talking to its API in Ruby.

If the term "rate throttling" is new to you, read Rate limiting, rate throttling, and how they work together

The Heroku API uses Genetic Cell Rate Algorithm (GCRA) as described by...


Over the last few years, GraphQL has emerged as a very popular API specification that focuses on making data fetching easier for clients, whether the clients are a front-end or a third-party.

In a traditional REST-based API approach, the client makes a request, and the server dictates the response:

$ curl https://api.heroku.space/users/1 { "id": 1, "name": "Luke", "email": "luke@heroku.space", "addresses": [ { "street": "1234 Rodeo Drive", "city": "Los Angeles", "country": "USA" } ] } 

But, in GraphQL, the client determines precisely the data it wants from the server....


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