The INVEST acronym is a guideline for writing well-formed user stories in Agile software development. It is especially useful in Scrum, where work is broken down into small, manageable pieces known as user stories. Here’s what each part of the INVEST acronym means in the context of user stories:
- Independent: Ideally, user stories should be independent of one another. This means that they can be worked on in any order and the implementation of one does not affect the implementation of another. This gives more flexibility in planning and prioritizing work.
- Negotiable: User stories aren’t contracts. They are brief, and the details are not worked out until they are about to be implemented, which means they can be changed and reworked. The team and the Product Owner should be able to negotiate the details of the user story to get the best value.
- Valuable: Every user story needs to provide value, and this value should be visible and understandable to the users or customers of the software. If the value of a story isn’t apparent, it might need to be rewritten or discarded.
- Estimable: It should be possible to estimate the size of a user story, to help with planning and prioritization. If a story is too large or complex to estimate, it might need to be broken down into smaller stories. If a story is hard to estimate because there’s too much unknown, it might be a sign that more analysis or a spike is needed.
- Small: User stories should be small enough to be completed within one sprint—meaning no more than a few days to a week of work for the team. If a user story is too large, it should be broken down into smaller stories.
- Testable: Finally, it should be clear how each user story will be tested. This usually means that each user story includes clear acceptance criteria. If it’s hard to determine how to test a user story, it may need to be clarified.
By following the INVEST criteria, you can ensure that your user stories are well-formed and ready to be worked on by your Agile team.
