brownfield

[ BROWN-feeld ]noun

Code that already exists and already works, which you now have to change without breaking it.

Explanation

This is most real work, and it is the hard kind. Most vibe-coding advice quietly pretends otherwise.

Related words

• greenfield — A brand new project with nothing in it yet, where the AI can write whatever it likes.
• characterization test — A test that writes down what code does today, right or wrong, so you can tell later whether you broke it.

Prompts that deal with it

• Reversible Migration — Every database change arrives with its undo
• Explain It Like I Own It — For the builder who did not write the code