Batching with partition
Sometimes data must be batch processed. Clojure’s got just what you need in partition . Read article
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Latest posts
On keys and their usage
In Clojure, you can namespace your keys — a seemingly trivial detail with major implications. Let’s explore how this helps with data modeling. Read article
An umlaut too far
Unicode is everywhere. But in some places, it’s still safest to use the good old ASCII character set, and in this post we’ll look at Unicode normalization as a way to get there. Read article
A week with Tailwind CSS
Close to a decade after everyone else, I finally tried my hand at Tailwind CSS. I found some good ideas, some bad ones, and a surprise or two. Read article
Continuously Indignant
Do pull requests conflict with continuous integration? Is continuous integration the same as CI? What about CI/CD? I try to clarify some confusion from my previous post about pull requests. Read article
All PR is good PR?
Pull requests are ubiquitous, even among in-house product teams. They’re so common as to be practically synonymous with using git. Is that a good thing? Should every change come through a pull request? I’m not so sure. Read article
Some letters are more equal than others
In the previous post, we looked at how full-text search works, treating all symbols in the index as equally important. But that’s not always how it works in practice — for instance, matches on whole words are usually better than matches on word fragments. This can be solved with weighting, which is today’s topic. Read article
Fulltext search from scratch
Imagine, all of Shakespeare’s collected works hidden in a box of alphabet biscuits. That’s roughly the approach we’ll take as we build a tiny search engine in JavaScript to understand how full-text search works. Read article
How I learned to stop worrying and love the API
As a follow-up to my post on backward compatibility , I’m sharing some practical tips today on how to design HTTP APIs that provide a great user experience over time. Read article
Stop Breaking My Stuff
The IT industry seems to love redoing old things. In our endless chase for the perfect API, we throw out things that work just fine, just to serve up something that looks different on the surface but does basically the same thing underneath. It’s more trouble than it’s worth. Read article
Stateless, data-driven UIs
A practical example of how to write stateless, data-driven UIs Read article
First-Class Analytics
Web analytics for 100% of users without dreadful consent dialogs is possible — here’s how. Read article
Simpler and Better Modals
All modern browsers now include a built-in building block that helps us create accessible modals with less code. If you, like me, had no idea this existed, then this post is for you. Read article
Walking is good for you
There’s a lot to enjoy in Clojure: pure functions, immutability, and the REPL, to name some of the big things. Today, let’s instead look at two tiny but very useful functions. Read article
What's the domain of the frontend?
A prerequisite for hitting the mark with software design is having good control over the domain you operate in. But what exactly is the domain of your frontend code? Read article
What Exactly Is a REPL?
The REPL breathes life into your program and lets you develop it from inside the running process. Join me as I try to explain exactly why a REPL is the essential tool you might not know you’re missing in your (work) life. Read article
Zero downtime Kubernetes deployments
When you deploy your app to that spaceship of a rig called Kubernetes, it happens without any form of downtime, right? Bad news: unless you have actively worked for it, your services most likely have some downtime during deployment. But why? Read article
Continuous Delivery on the Frontend
You have a Single Page Application (SPA). Users typically keep the app open in their browser for a long time - many days, or even weeks. At the same time, you’re pushing out new versions several times a day. How on earth do you ensure that people don’t end up stuck on an old frontend that may have bugs you’ve already fixed, or are using an outdated API client? Well, here’s…
Achieve more by doing less
A short story about how a new feature in an open source library was scaled down and yet became more useful. Read article
Partitioning data
Functions like map , filter , and reduce are useful tools that many developers keep in their toolbox. partition may not be as commonly known, but in this post I’ll show you why it should be. Read article
Proper URLs for your SPA on S3 behind Cloudfront
In this post I’ll show you how to use Lambda@Edge to give JavaScript frontends (“Single Page Applications”) on AWS S3 behind Cloudfront proper URLs even when all you have is a single HTML file and some JavaScript. Read article
Editing for cleaner merges
As we add new code to existing files, it feels natural to append – add new functions at the end of the file, new requires at the end of the list of requires, and so on. This approach introduces some friction, and in this post I’ll share some pointers for improved editing and git workflow. Read article
Devops! Dev? Ops!
There is currently no shortage of companies in the IT world boasting about doing Devops. But are they really? If the solution is a “devops team” or job ads for “a devopser,” unfortunately the chances of getting the best that devops has to offer are slim. Read article
JavaScript Coercion 101
Developers love pointing out the madness in JavaScript, like [] + 2 === "2" , but if your job is to write code in this language, or languages that compile to JavaScript without hiding this behavior (for example TypeScript and ClojureScript), you will save a lot of time debugging and coding by understanding why things are the way they are. Read article
When the AWS Bill Skyrockets
It’s easy to get up and running in the cloud. Unfortunately, it’s also much too easy to end up in a situation where you’re practically throwing money in Amazon’s direction. What do you do when you discover that the AWS bill is much higher than you expected? Read article
AWS Free Tier
This is a short story about how EFS almost killed our Kubernetes cluster, and how you can avoid ending up in the same pickle — even if you don’t use EFS. Read article
CSS Grid
CSS grids have finally given us a simple and flexible model for web layout. With just a few properties, you can pretty much retire float , gain full control over source order, and get a powerful tool for responsive design in the bargain. Read article
Clojure in Production with tools.deps
A lean and fast setup for packaging Clojure applications for production using tools.deps Read article
tools.deps, figwheel-main, Devcards, and Emacs
A primer on setting up a ClojureScript project with tools.deps, figwheel.main, devcards, and optionally Emacs. Read article
A Unified Specification
An approach to describing the structure of data in ClojureScript applications in one place, and using it to power Datascript schemas, specs, and coercions for data from external sources. Read article
Git Subtree for Multiple Directories
How to split Git repos. Read article
Processing data with Clojure and Go
Porting some recent Go code to Clojure, and musing a little about the difference between these two languages when it comes to data processing (performance, typing, etc). Read article
A Better Playlist Shuffle with Go
Shuffling music playlists with less random and more cleverness, using Go. Read article
Webslides Syntax Highlighting with Prism
Adding Prism.js syntax highlighting to webslides. Read article
Optimized Optimus Asset Paths from ClojureScript
How to write a Clojure macro that exposes Optimus’ optimized paths to the client-side ClojureScript build. Read article
Securing HAProxy sites with Let's Encrypt TLS Certificates
A step by step howto on setting up Let’s Encrypt TLS certificates with HAProxy. Read article
Setting up an Api Gateway Proxy Resource using Cloudformation
How to configure an AWS Api Gateway catch-all endpoint to proxy to another HTTP service with Cloudformation. Read article
Idempotent Cloudformation Updates
A guide to making Cloudformation updates idempotent. Read article
Annotating Datomic transactions
Datomic creates a transaction entity every time you transact data. These entities can be freely extended for a multitude of use cases. Read article
Querying across Datomic databases
Among its many, many unique and interesting features, Datomic supports datalog queries across multiple databases. I recently had a chance to actually use this feature, and thought I’d share an actual example of it. Read article
Referentially transparent CRUD
Managing side-effects functionally with Datomic’s transaction data. Read article
Clojure to die for
A selection of the details that makes Clojure such an enjoyable language to work with. Read article
Building static sites in Clojure with Stasis
An in-depth code-along guide to building static web sites powered by the Stasis library. Read article
An introduction to Emacs Lisp
A long, thorough introduction to programming in Lisp in general, and Emacs Lisp in particular Read article