Understand what tail recursion with this visual aide and example in Zig.

Tail Recursion

Learn how classes focused on holding data can clean up type definitions and provide discriminants for your TypeScript code.

Data Classes in TypeScript

Learn how to rapidly extend your test boundaries to the database without losing speed or introducing flaky tests.

Isolating PostgreSQL Tests with PGLite

Learn more about PostgreSQL indexing practices and performance measurement in this blog post.

PostgreSQL Performance

Exploring Uber multi-tenancy paradigms and seeing how they can impact testing in TypeScript.

Multi-tenant testing

Customize your TS Rest API calls to enable capabilities such as retries, timeouts and span information

Retries, timeouts and spans for TS Rest clients

Understand how JSON Web Key Sets served from .well-known endpoints enable you to dynamically verify JSON Web Tokens (JWTS).

Well Known JSON Web Key Sets (JWKS)

Understand how mutual transport layer security works (mTLS), configure your own chain of trust and see real-world use cases.

Mutual Transport Layer Security (mTLS)

Ever wondered how to configure your own API keys? This blog post explores API key design options and trade-offs.

Roll Your Own API Keys

Learn how to increase your testing confidence vector with principles and tools like MSW and testcontainers.

The Boundaries of TypeScript Testing

A set of guidelines to reduce code management and improve developer experience in 2025

Effective TypeScript Principles in 2025

A reflection on a recent codebase change where the choice came between handling exceptions from middleware or controlling responses from the controller.

Better .NET Controllers with OneOf

Take a look into AWS' recently announced distributed Aurora SQL solution, now in preview!

AWS Aurora DSQL in Action

An exploration on how Git Worktree makes stash redundant and saves you headaches across large changes.

Exploring Git Worktree

Learn to express your thoughts and opinions better with this guide.

Expressing Your Thoughts in Software

We look into implementing the Acquire and Release Pattern in TypeScript for creating a sequence of operations with compensating actions on failure.

Resource Management in TypeScript

In this blog post, we take a look at libraries such as EffectTS, Zod, Valibot and Joi to understand how they approach a Result-like type and how we could approach building our own.

Creating a Result Type in TypeScript

We tie together everything that we've learned so far about Node.js streams and apply it through a practical example using the AWS CDK, AWS S3 and AWS Transfer Family.

Node.js Streams in Action with the AWS CDK

We looking into the pipeline function from the Node.js stream module.

Stream Pipelines in Node.js

What are Transform streams in Node.js? How do they work? We cover the fourth and final fundamental stream type in this post.

Transform Streams in Node.js

What are Duplex streams in Node.js? How do they work? We cover the third fundamental stream type in this post.

Duplex Streams in Node.js

What are Writable streams in Node.js? How do they work? What are some common use cases for Writable streams? We continue our exploration into streams in this post.

Writable Streams in Node.js

What are readable streams in Node.js? How do they work? What are some common use cases for readable streams? Let's explore these questions in this post.

Readable Streams in Node.js

Everything you need to prepare yourself to know Node.js Streams.

Understanding Node.js Streams

Learn what a Buffer is in Node.js, how to think about it and how it is useful.

Node.js Buffers Explained

Learn how we can use InversifyJS to help dependency injection with it's inversion of control container.

Dependency Injection with InversifyJS

Go 1.22 comes a brand new built-in router option for more complicated server applications. This is a basic dive in for Golang first timers.

Up and running with Go 1.22's new built-in router

Ever wondered how design systems provide an 'as' prop for their components that you can use to inject or change the component type? Let's look at how we can do this with TypeScript.

Type-safe usage of React as a prop for flexible components

After another failed hard drive meant losing data, I decided to look into mounting my own cloud storage. Here is how I did it.

Mounting Your Own Cloud Storage With Cloud Mounter and AWS

This post is for you if you are migrating across from a Prisma application or just want to check out the performance difference with DrizzleORM.

Using Prisma For Migrations And DrizzleORM For Querying

Understand the Node.js profile flag by improving an inefficient approach to getting unique elements from an array.

Node.js --prof and --process-prof flags

One of the JavaScript ecosystems biggest pain points. What are they and why do library maintainers hurt inside when they have to support them all?

Explaining CJS vs AMD vs UMD vs ESM

A walkthrough on setting up a basic Express.js application and writing tests using Supertest for robust APIs.

Mastering API Testing with Supertest, Express.js, and Jest

Join me as we dive deep into TypeScript's type operators, including keyof, index types, and index signatures. I'll be guiding you through practical examples that you can follow along with in the TypeScript Playground. Master these powerful tools with me to boost your TypeScript's code reliability and predictability with an advanced type system.

Diving Into Typescript's Type System: Type Operators

See how TypeScript is used with async promises.

Typescript And Promises: Conquering Asynchronous Programming

Implement your own map function with TypeScript.

Typescript And Functional Programming

A practical explanation of how union and intersection types work.

Advanced Union And Intersection Types In Typescript

This post covers the basics of modules in TypeScript.

Typescript Modules For Organizing And Sharing Code Effectively

See how we can use the TypeScript operator keyof to dig into our types.

Harnessing The Power Of The keyof Operator

A look at different implementations of generics for more specific use cases.

Advanced Typescript Generics In Practice

Decorators, a proposed feature for JavaScript, are already available as an experimental feature in TypeScript. See an example of decorators in action in this post exploring the topic.

TypeScript Decorators: An Introduction To Metadata And Annotation

Implementing custom type guards for a complex type validation with deep object structures.

Ensuring Type Safety With Type Guards

Get started with the new Vercel AI SDK in this quick demo with NextJS.

Next.js + Vercel AI Package In Action

Mapped types are a powerful feature that enable us to take existing types and generate new types from them on the fly.

Exploring Typescript Mapped Types And Transformations

See the T extends U ? X : Y syntax in action with simple examples.

Mastering Conditional Types In Typescript

Advanced Use Case: Exploring type inference with conditional types and more complex generic patterns.

Understanding Advance Type Inference In Typescript

Learn how you can statically generate pre-determined Next.js pages using a database for improved build times while still allowing for dynamic content to be generated on the fly.

The Benefits of Combining Static Site Generation with Incremental Static Regeneration

Ever wanted to better understand the unknown type? This blog post walks you through a practical setup and look at working with the unknown type.

A Practical Look At The "Unknown" Type In Typescript

Following the release of Satori and Vercel's new open graph image generation, follow along as I demonstrate how I updated my own open graph images for the blog.

Using The New Vercel Open Graph Image Generation

A look at implementing beautiful graph UI components quickly with Tremor.

Exploring the Tremor dashboard UI library

This post focuses on my work at Visibuild to roll-forward a feature to a more scalable solution.

Iterating on our bulk Visi exports feature

Peel back some of the magic behind discriminated union in TypeScript and how they impact your workflow.

Discriminated Unions In Typescript

Help understand your Rails models easier with the help of the annotate models gem.

Annotated Rails Models

Set up ActiveStorage on your local developer environment with Rails 7.

Local ActiveStorage Development With Rails 7

A short overview on how you can mock both class methods and instance methods when dealing with Minitest.

Mocks With Minitest

Some basic tips on getting more value from the Pry debugger.

Pry Debugger Tips

A quick look at using the SmarterCSV gem.

Ruby SmarterCSV Gem

See how you can use Sidekiq jobs to read and process a local YAML template for populating the database.

Processing Local YAML Files With Sidekiq

See how to upload files to ActiveAdmin using this example that uploads a CSV file and populates data to the database.

Uploading Files In ActiveAdmin

In the final part of the Ruby Gem series, we will be automating the deployment of our recently created gem using GitHub Actions.

Automating Ruby Gem Package Releases With Github Actions

In this post we will take our basic code from the previous exercises and package it up as a Ruby gem to install in other projects.

Creating Your Own Ruby Gem

In part two of the Ruby gem series, we will take the gem we created in the previous part and deploy it to RubyGems.

Deploying Your Gem To RubyGems

In this short overview, see how MiniTest can be incorporated into your GitHub Actions workflows.

MiniTest With GitHub Actions

In this short overview, see how RSpec can be incorporated into your GitHub Actions workflows.

RSpec With GitHub Actions

In this short post, see how you can visualize your domain model quickly using the rails-erd gem.

Rails Entity-Relationship Diagrams

Following up on the previous post, we will be looking at the last through associations that come baked into Rails.

Through Rails Associations

In part ten of the Devise series, we start a new project from scratch to explore how the devise-token-auth gem can be setup with a Rails 7 application.

Devise Part 10: Devise Token Auth

In part eleven of the Devise series, we continue on with the previous project to add the capability of authenticating to a public API using authentication tokens with Doorkeeper.

Devise Part 11: Authentication Tokens With Doorkeeper

In this post, we go through all six of the possible Rails associations with visualizations to help us understand what associations are supported and how they work in Rails 7.

Understanding Rails Associations

This post is a reflection on my first look at using Ahoy analytics in a Rails 7 application.

Exploring Ahoy Analytics With Rails 7

ActiveAdmin is a powerful gem to help us generate admin panels for our internal usage for Rails applications. This post will cover the basics of getting up and running with ActiveAdmin and Ruby on Rails 7.

ActiveAdmin With Ruby On Rails 7

See how the FriendlyID gem makes it simple to convert you URLs into something more useful and friendly with Rails 7.

Getting Started With The FriendlyID Gem In Rails 7

An intro into Ruby memoization with the memoization operator and the Memoist gem.

Ruby Memoization Basics And Memoist

See how to setup SimpleCov for your RSpec tests in a simple Ruby setup and then implement a GitHub Action to comment the coverage results in a pull request.

SimpleCov With Ruby And GitHub Actions

For this part, we look at setting up some helpers for us to log users in when writing controller tests.

Devise Part 7: Testing With RSpec And Factory Bot

This post looks at how we outline required policies in order to fulfill requests in Ruby on Rails using the Pundit gem.

Devise Part 8: Policy Authorization In Rails 7 With Pundit

In part nine, we take a look at how we can set up our API endpoints to return a 401 response if a user is not signed in instead of the default 302 redirect to the login page.

Devise Part 9: Setting Up 302 Redirection vs 401 Unauthorized Handlers

This post will demonstrate how to benchmark and compare code to help us better understand the performance of our Ruby code.

Benchmarking In Ruby

In part five, we set up the OmniAuth configuration for Devise to demonstrate login using GitHub.

Devise Part 5: OAuth With GitHub And OmniAuth

In part six, we enforce the usage of reCAPTCHA v2 to prevent signing up or logging in without passing the reCAPTCHA verification.

Devise Part 6: Adding Recaptcha To Prevent Fraud And Abuse

Follow the basics to send an email using a Postmark template and view it in the browser during development.

Sending Your First Email With ActionMailer In Rails 7

In part one of this six part series on Devise and Ruby on Rails, we demonstrate setting up Devise for Rails 7 with a basic sign up and login flow.

Devise Part 1: Setting Up Devise With Rails 7 And React

In part two of our Devise series, we look at how we can replace the default cookie session store with Redis.

Devise Part 2: Using Redis Sessions Instead Of The Cookie Store

In part three of the series, we walk through how to add TailwindCSS to a Rails 7 project and spruce up our sign in page.

Devise Part 3: Updating Our Devise Views With Tailwind CSS

In part four, we add in a separate Next.js project into the mix and demonstrate how to organize authentication for our main Rails API.

Devise Part 4: Authentication With A Separate Frontend

In the second of two posts, we look at setting up rate-limiting with the rack-attack gem to see how we can limit requests to our API.

Rate Limiting With Rack Attack In Rails 7

This is the first of two posts that will look at rate limiting in Rails application. This post will focus on the rack-throttle gem and its usage with Redis.

Rate Limiting With Rack Throttle In Rails 7

A demonstration on getting a local development environment going with Sidekiq and Redis to run a simple demonstration job in Rails 7.

Getting Started With Sidekiq In Rails 7

An entry-level introduction to setting up the Rails cache and seeing it in action with Redis in development.

Using The Rails Cache With Redis

Implement simple pagination mechanisms using the Kaminari gem with Ruby on Rails 7.

Ruby On Rails Pagination With Kaminari

Continuing on from the last post, we introduce Redux to handle our remote messages and perform actions on our React.js application.

Action Cable Messages With Redux

Dive head-first into using Action Cable with Rails 7 and setup a basic React project that can handle web sockets.

Action Cable Hello World With Rails 7

At this stage of the project, we are introducing Factory Bot to help replace the default fixtures so we can test our PostsRepository code.

Factory Bot With Rails

Continuing on with our project, the next step is to add in dry-validation and dry-monads to help tidy up our code.

Dry Validation With Rails

A look at how we can implement a Railsy-way of the Repository Pattern in our Rails apps.

Repository Pattern In Rails

See how we can use the Dry RB gems dry-matcher and dry-monads to clean up our Ruby code.

Exploring Dry-RB With Dry Matcher And Dry Monads

Follow along as we build out a skeleton Rails 7 server that enables us to use GraphQL.

Setting Up A Base GraphQL Server And GraphiQL With Rails 7

Set up a new Rails 7 project with ESBuild that has TypeScript support out-of-the-box.

Rails 7 Using React With ESBuild

See how you can update your new Ruby on Rails 7 project to use HTM and React without a Node.js setup.

Rails 7 Using React With Htm

This guide will alleviate questions that new Rubyists have around monkey patching and how it works in Ruby.

Dennis O'Keeffe

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Dennis O'Keeffe