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How-to guides, tooling tips and real-world advice for developers and product managers tired of broken software. Let’s fix this mess together.

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How-to guides, tooling tips and real-world advice for developers and product managers tired of broken software. Let’s fix this mess together.

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Tradeoffs chart for changeability, cost, and reliability

What is legacy software in the age of AI?

Software becomes legacy by succeeding long enough to accumulate the weight of every decision and shortcut made along the way. Users feel it as friction. Engineers feel their momentum slip. The business watches costs climb. AI changes two of those. The third may be getting worse.

Todd Kaufman

Legacy modernization

Three people emerge from darkness toward light and a neon green path

In the age of AI we’re in this together

River Lynn Bailey

River Lynn Bailey

Cognitive hazard study diagram showing a laptop, coffee mug, and documentation sinking into a tarpit

Organizational observability: The AI alignment problem starts upstream

Dave Mosher

$Puzzled math meme with a rubber duck wearing a fedora and trench coat$

The shockingly simple math for why we need test automation

Gabriel Côté-Carrier

Gabriel Côté-Carrier

Double Takes

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Double Takes

TDDing with Claude is like having a pair that removes all the failing assertions every time you go to the bathroom.

Steve Jackson

State machines are the answer for those seeking determinism in the era of AI agents.

Dave Mosher

A Slack conversation left Doc reflecting on what bug bashes say about the systems we work in.

Doc Norton

Test-driven development is to programming what double-entry bookkeeping is to accounting.

Neal Lindsay

The fundamental character flaw of the software creator is not the misguided belief that they can solve any problem with software. Instead, it is the belief they can understand how their own software works before they create it.

Steve Jackson

We may need a SaaS appendix for Zawinski's law:

Any SaaS platform attempts to expand until it is a social network.

Matt Jones

Embracing clarity: Shifting away from a culture of certainty

If your organization feels stuck, and you’re continuing to push features that seem to fail in the marketplace, perhaps you’re stuck in the Culture of Certainty. That’s okay, because you’re not alone.

Michael Toland

Communication & teams

communication

product-innovation

professional-growth

teams

Code generation tools are easy to start, but hard to master

Software consultant Daniel Huss has experimented with using Copilot. Here's his review of code generation tools as a developer.

Daniel Huss

ai-ml

How product managers turn ideas into profit (and prevent disasters)

Product managers do more than prioritize backlogs—they help align strategy, reduce waste, and deliver software that customers love, ensuring long-term success.

Test Double Editorial Board

Test Double Editorial Board

Product management

budgeting

kpi

Icon illustration showing a speaker blasting noise that overwhelms a person

Work around Rails schema noise with one weird trick

Discover a simple and effective trick to handle unwanted changes in db/schema.rb on your Rails projects. Perfect for lazy developers!

Kevin Baribeau

Software tooling & tips

rails

testing

Airplane taking off

From aerospace to DevOps: 4 surprising lessons for better software

Think compliance is boring? Think again! Discover how lessons from high-risk industries can lead to high-quality, sustainable code that saves time and money. 🚀 #DevOps #SoftwareDevelopment

James Zimmerman

James Zimmerman

DevOps & security

regulatory-compliance

consulting

Getting the exercises in Programming Flutter working

Flutter and Dart have had some updates since the book Programming Flutter was published in 2020. Let's look at the updates that will allow you to get the exercises in the book working.

Josh Justice

Software tooling & tips

flutter

Terminal screen showing Typescript example

A quick guide to TypeScript conditional types

Discover how to leverage TypeScript conditional types to enhance your code's type accuracy and reusability. Get practical tips and elevate your TypeScript skills.

Lewis M Sparlin

Lewis M Sparlin

Software tooling & tips

typescript

automation

javascript

14 tools every Ruby developer will love for performance and debugging

Discover 14 of the best tools and gems for Ruby developers, with top picks for feedback loops, performance, debugging, and data management.

Joé Dupuis

Software tooling & tips

rails

postgres

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