eferro’s Substack

Scaling Systems and Teams: Five Mental Models for Engineering Leaders

Introduction: It’s Not Performance, It’s Scalability

Nov 23 • 

eferro

2

1

2

Pseudo TDD with AI

Exploring Test-Driven Development with AI Agents

Nov 11 • 

eferro

My Base Setup for Augmented Coding with AI

Repository: eferro/augmentedcode-configuration

Nov 10 • 

eferro

3

1

1

Mutation Testing: When “Good Enough” Tests Weren’t

For weeks, I had been carrying this nagging doubt.

Nov 9 • 

eferro

3

When AI Makes Good Practices Almost Free

Since I started working with AI agents, I’ve had a feeling that was hard to explain.

Nov 4 • 

eferro

5

October 2025

AI and Lean Software Development: Reflections from Experimentation

Exploring how artificial intelligence might be changing the rules of the game in software development - preliminary insights from the trenches

Oct 11 • 

eferro

2

2

2

Lean + XP + Product Thinking – Three Pillars for Sustainable Software Development

When we talk about developing software sustainably, we’re not just talking about taking care of the code or going at a reasonable pace.

Oct 6 • 

eferro

5

1

September 2025

August 2025

Optimize the Whole: From Lean principle to real-world practice

Introduction

Aug 11 • 

eferro

1

1

June 2025

YAGNI and the Value of Learning: An Additional Premise

For years, I’ve been applying—almost without realizing it—an extension of the YAGNI principle that I want to share.

Jun 21 • 

eferro

3

1

Overcoming resistance and creating conditions for quality

Fifth article on quality in Lean Software Development.

Jun 8 • 

eferro

3

May 2025

Lean Software Development: Quality through Collaboration and Visibility

Fourth part of the series on quality in Lean Software Development.

May 25 • 

eferro

3

1