# SRS: make ‘done’ mean something

Turn a wish into requirements someone can actually test.

ID: srs
Language: en
Revision: 2
Translation source revision: 2
Canonical: https://jujin.dev/en/guides/srs/

## Concept

A software requirements specification (SRS) describes observable behavior and constraints. Acceptance criteria make requirements checkable.

## Example

Given an empty cart, adding the same book twice creates one row with quantity 2. Unavailable stock leaves it unchanged.

## When to choose it

Checklists are lightweight; user stories explain motivation; detailed specifications coordinate teams but need more maintenance. Write numbered requirements with success and failure cases. Add measurable limits only with a justified measurement method. [NASA](https://swehb.nasa.gov/display/SWEHBVD/SWE-050+-+Software+Requirements)