Relevant Mutants in a Flash

Relevant Mutants.

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• Not all surviving mutants indicate weaknesses in tests.
• Not relevant surviving mutants (don’t signal any test weakness):

  • Ignore these ones:

    • In dead code (unreachable code)
    • In legacy seams (intentionally excluded from test execution).
    • Code not used because of legacy seams (also intentional).

  • Mutants in superfluous code:

    • They survive because the mutation did not change any behavior.
    • Still useful 💰: signal a possible simplification (refactoring opportunity).
• Relevant surviving mutants 💰: reveal genuine gaps in the test suite
  • e.g. missing boundaries, too lenient assertions, etc.
• Read Relevant Mutants.

Books I read (January - February 2026)

January
- The Fraud, Zadie Smith
- Son de Mar, Manuel Vicent
- Alien Clay, Adrian Tchaikovsky
- Misterios de Madrid, Antonio Muñoz Molina
- Simple Rules: How to Thrive in a Complex World, Donald Sull, Kathleen M. Eisenhardt
- The war of art, Steven Pressfield
- Solving the procrastination puzzle, Timothy A. Pychyl

February
- Ava en la noche, Manuel Vicent
- Dream Count, Chimamanda Ngozi Adichie
- Saturday night and Sunday morning, Alan Sillitoe
- Vibe Coding, Gene Kim, Steve Yegge

Interesting Talk: No Vibes Allowed: Solving Hard Problems in Complex Codebases

I've just watched this great talk by Dex Horthy

• No Vibes Allowed: Solving Hard Problems in Complex Codebases

Interesting Talk: From Vibe Coding To Vibe Engineering

I've just watched this funny talk by Kitze:

• From Vibe Coding To Vibe Engineering

Interesting Video: Does Code Quality Matter When AI Writes the Code?

I've just watched this interesting video by Tim Corey

• Does Code Quality Matter When AI Writes the Code?

Interesting Talk: Making Codebases Agent Ready

I've just watched this great talk by Eno Reyes

• Making Codebases Agent Ready

Interesting Talk: Can you prove AI ROI in Software Eng?

I've just watched this great talk by Yegor Denisov-Blanch

• Can you prove AI ROI in Software Eng? (Stanford 120k Devs Study)

This is a continuation of the study that appears in his previous talk: Does AI Actually Boost Developer Productivity? (100k Devs Study)

Interesting Talk: Using AI to Refactor Legacy Code: A Practical Guide

I've just watched this interesting talk by Scott Wierschem:

• Using AI to Refactor Legacy Code: A Practical Guide

Interesting Talk: Don’t get one-shotted: Use AI to test, review, merge, and deploy code

I've just watched this interesting talk by Tomas Reimers:

• Don’t get one-shotted: Use AI to test, review, merge, and deploy code

Interesting video: Claude Code is all you need in 2026

I've just watched this interesting video by Brian Casel

• Claude Code is all you need in 2026

Interesting Talk: Dispatch from the Future: building an AI-native Company

I've just watched this interesting talk by Dan Shipper:

• Dispatch from the Future: building an AI-native Company

Interesting Talk: Vibe coding and the evolution of developer experience tools

I've just watched this interesting talk by Harsha Shivanna:

• Vibe coding and the evolution of developer experience tools

Interesting Interview: Vibe Coding Solved What I Couldn't in 13 YEARS

I've just watched this great interview with Gene Kim on Tech Lead Journal channel

• Vibe Coding Solved What I Couldn't in 13 YEARS

Interesting Video: When to Vibe Code?

I've just watched this super interesting video by Graham Lee on a new dimension of technical debt in vibe-coded solutions:

• When to Vibe Code?

Interesting Talk: From autocomplete to agents: AI coding assistance state of play

I've just watched this interesting talk by Birgitta Böckeler

• From autocomplete to agents: AI coding assistance state of play

Interesting Talk: Automated software refactoring with OpenRewrite and OpenAI

I've just watched this interesting talk by Olga Kundzich and Sam Snyder

• Automated software refactoring with OpenRewrite and OpenAI

Interesting Talk: AI Hates Legacy Code

I've just watched this great talk by Ray Myers

• AI Hates Legacy Code

Interesting short conversation: How Agents Decide What to Use and When

I've just watched this great short conversation by Guy Podjarny and Simon Maple

• How Agents Decide What to Use and When

Interesting Talk: AI Coding: The State of The Mend

I've just watched this great talk by Ray Myers

• AI Coding: The State of The Mend

Interesting Video: Agents are Easy. REALLY : A Vibe Coding Journey

I've just watched this interesting video by Matt Maher

• Agents are Easy. REALLY : A Vibe Coding Journey

Interesting Talk: Self Coding Agents

I've just watched this great talk by Colin Flaherty

• Self Coding Agents

Interesting Talk: Playing the long game

I've just watched this great talk by Sheena O'Connell

• Playing the long game

Interesting Talk: Beyond Code: The Role of Developers in the Age of AI

I've just watched this great talk by Kesha Williams

• Beyond Code: The Role of Developers in the Age of AI

Interesting Talk: Making AI coding assistants better, even for your weird DSLs

I've just watched this great talk by George Fahmy

• Making AI coding assistants better, even for your weird DSLs

Interesting Talk: AI assisted programming: from inline completions to agentic workflows

I've just watched this great talk by Anton Arhipov

• AI assisted programming: from inline completions to agentic workflows

Interesting Talk: Large-scale refactors with Agents

I've just watched this great talk by Robert Brennan

• Large-scale refactors with Agents

Interesting Talk: Automating Large Scale Refactors with Parallel Agents

I've just watched this great talk by Robert Brennan

• Automating Large Scale Refactors with Parallel Agents

Interesting Talk: Beyond Tests What to Verify in AI Generated Code

I've just watched this great talk by Jennifer Sand and Brandy Pielech

• Beyond Tests What to Verify in AI Generated Code

Interesting Talk: Agent Skills, Rules, Subagents: Explained!

I've just watched this great short talk by Lee Robinson

• Agent Skills, Rules, Subagents: Explained!

Interesting Podcast: Don’t Trust AI Reporting! (Three Traps to Avoid)

I've just listened to this great podcast by Cal Newport

• Don’t Trust AI Reporting! (Three Traps to Avoid)

The discussion about AI Reporting traps occurs during the first 29 minutes of the podcast.

Interesting Talk: We Studied 150 Developers Using AI

I've just watched this interesting short talk by Dave Farley

• We Studied 150 Developers Using AI

Interesting Talk: How I Tamed Claude

I've just watched this interesting talk by Emmz Rendle

• How I Tamed Claude

Interesting Talk: Relax

I've just watched this interesting talk by Maximilian Schwarzmüller

• Spec-Driven Development in the Real World

Interesting Talk: "I shipped code I don't understand and I bet you have too"

I've just watched this interesting talk by Jake Nations

• "I shipped code I don't understand and I bet you have too"

Interesting Talk: The New Code

I've just watched this interesting talk by Sean Grove

• The New Code

Interesting Talk: ChatGPT & Copilot are NOT Refactoring Tools

I've just watched this interesting talk by Emily Bache

• ChatGPT & Copilot are NOT Refactoring Tools

Interesting Talk: Can Claude help with legacy code?

I've just watched this interesting talk by Alex Bolboaca

• Can Claude help with legacy code?

Interesting Talk: Augmented Coding: Mapping the Uncharted Territory

I've just watched this interesting talk by Lada Kesseler

• Augmented Coding: Mapping the Uncharted Territory