Volumes and bind mounts let you share files between the host machine and container so that you can persist data even after the container is stopped. If you’re running Docker on Linux, you have a third option: tmpfs mounts. When you create a container with a tmpfs mount, the container can create files outside the container’s writable layer. As opposed to volumes and bind mounts, a tmpfs mount is temporary, and only persisted in the host memory. Read more...

The remediation of the recent log4j security vulnerability has solidified an idea in my mind. Services and infrastructure must be regularly deployed to be considered healthy long-term. I’ve read through several Reddit threads where people in companies with a strong devops culture had an easier time doing the dependency update and deploy as opposed to others. The issue people tend to have were updating services that have had infrequent and/or manual deploys. Read more...

Hey everybody, thanks for signing up for my email list. I’m going to try to send something out at least weekly. This first newsletter I want to highlight a very useful Kubernetes feature that I started leveraging recently: port forwarding. You can bind a port from a kubernetes cluster to your development machine you can hit private endpoints on your kubernetes cluster. In the past week I’ve used it to access private endpoints and leverage a datadog agent that was on a cluster but not on my local development machine. Read more...

Table of Contents Background Gotchas with Actions on GitHub Enterprise Server Caching isn’t available GitHub Enterprise Server is behind GitHub Enterprise Cloud Using Public GitHub.com Actions Dockerhub pull rate limiting General Limitations No dropdowns for manually triggered jobs Self-hosted runner default labels You can’t restart a single job of a workflow Slow log output You can’t have actions that call other actions Metrics and observability Workflow YAML Syntax can confusing Closing Background I’ve been leading a team at my dayjob to migrate every engineering team to GitHub Actions (GHA) Read more...

Say you’re a developer working on a feature, and you want to get early feedback from other teammates. How would you go about it? Most companies don’t have a good process for this, and it ends up crippling their ability to ship features and iterate. The process at companies without review app environments: An engineer works on a UI feature that she wants to get some early feedback on how it looks and feels. Read more...

The latest version of macOS (Catalina) includes zsh by default instead of bash. I’ve been using zsh for many years and along the way I’ve started using a handful of tools that make me more productive in my terminal. asdf (version manager) asdf is a plugin-based version manager. For example, instead of using nvm to manage node versions and rvm to manage ruby versions, you can use asdf to manage everything in one tool. Read more...

When you first start learning Clojure, you’ll eventually come across the loop/recur construct that enables you to essentially do tail recursion. Why does Clojure need to have loop/recur when you can simply use a function and call it again? Let’s say you’re writing a tail-recursive (iterative) function that calculates the nth fibonacci number. Since we’re recursing from the tail position, what’s the difference between calling the function by its name: Read more...

Many people coming to Clojure are often coming from Ruby, Python, or Javascript: These languages have their own set of web frameworks, both small and large. Examples of web frameworks are Flask and Django for Python and Sinatra and Rails for Ruby. What typically happens is they learn the basics of Clojure and want to do a more tangible project. Since the majority of people are coming from a web development background and that’s what the majority of people use Clojure for, that’s what they start with: Read more...

UPDATE: 2017-05-12 A few more thoughts have come to mind after writing the original post. I realized that I didn’t talk about the clojurescript side of things. Clojurescript provides a great alternative to plain javascript or ES6. The thing about clojurescript is clojurescript has the clojure standard library, which includes many more functions than javascript. The left-pad incident made me realize how weak a standard library javascript has. People need to write so many tiny libraries in order to get functionality that would exist in other languages. Read more...

People coming from opinionated frameworks like Ruby on Rails often become disoriented in a Clojure project. Rails, being a framework, has the code already organized for you. You just had to learn where to put your models, views, and controllers. Clojure doesn’t have a major opinionated framework like Ruby on Rails that forces you to follow its conventions. A lot of beginners get confused and have questions like the following: Read more...