Regression: what it means

How it shows up when you build

• Fix one thing: A fix can break something that worked. Re-run the checks after every edit and compare the change report.
• Change one thing without breaking the rest: When a change breaks something that used to work. AI edits cause them often because the model rewrites more than you asked for.

A tip

• Use the pattern: 'Change only X. Keep everything else exactly the same.'
• Keep a list of what works and click through it after every change.

Practise it

Build it with an AI tool and check the result in these exercises:

• 3. Fix one thing (Targeted edits)
• 1. Change one thing without breaking the rest (Scope a change)

Related terms

Audit, Checks, Diff thinking, Prompt, Scoped change, Scoped edits