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Comment by blowski | Hacker News Reader

Behavioural driven development (BDD) encourages this process. The developers flesh out specific examples with the business people using readable language, and that becomes user acceptance criteria.

It's no panacea, but it helps because it tries to prevent the business people dictating tech specifics, which the developers take too literally.

For example, a business person says "when I press the submit button the results must be stored in MySQL". What they really mean is that whatever they entered into a form must be accessible later, but the developers now believe they must use MySQL and have submit buttons.

By focusing on the "When I complete the form with data x, when I look at the form again later, then I see data x" you've moved the conversation to the business requirements and away from the perceived technical requirements.

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> It's no panacea, but it helps because it tries to prevent the business people dictating tech specifics, which the developers take too literally.

> For example, a business person says "when I press the submit button the results must be stored in MySQL". What they really mean is that whatever they entered into a form must be accessible later, but the developers now believe they must use MySQL and have submit buttons.

So in other words business people are plain old lying about the requirements.

Not lying, just not really understanding what they're talking about. For many BAs, 'MySQL' is interchangeable with 'database' so they don't realise that a different database might be a better solution. They're phrasing the requirement in terms of their best understanding of the implementation. The goal of BDD is to focus the language on the business domain instead.

Yes, I've often seen business people pick up on technical terms without really understanding what they mean. It is our responsibility to coax users into giving non-technical requirements.

> For many BAs, 'MySQL' is interchangeable with 'database' so they don't realise that a different database might be a better solution.

One minute of googling can be expected from BAs, too.

> They're phrasing the requirement in terms of their best understanding of the implementation.

Then they should say "to my knowledge MySQL is a popular database that I know of and is to my knowledge used a lot in the company, but if you know of a better implementation (I don't know much about that - I'm no computer scientist) use it instead.".

Or it's the developer's job to ask "why do you say that?" - the BA thinks they're being helpful and shortcutting a decision for you; the least you could do is try to be helpful back.

> the BA thinks they're being helpful and shortcutting a decision for you; the least you could do is try to be helpful back.

Giving an exact specification is a statement that you want it this way. It is a property of an executive position to give correct instructions to the subordinates. If they are not capable to do that they are simply not qualified for their job. On the other hand: If you want feedback for your specification, ask for it. Giving instructions means "you implement it this way and I am personally responsible with my honor that this is indeed what is needed".

You seem to have a very rigid view of the business world. That is fine, but you are very likely to find yourself to be more effective if you can adopt a more flexible outlook, where you see peoples' competency in their jobs as a continuum rather than black and white, and where you see instructions as conversations rather than rigid honor-bound orders (unless you're in the military). Many have tried to make the organizations around them reflect their rigid prescriptions for how things should be done, and they mostly just succeed in making people dislike working with them.

Maybe it's like that where you work. But if I was the BA and was having to be personally responsible for something I would want to make sure that what I was specifying was actually correct by discussing it with the people who will be doing the work. Because that responsibility cuts both ways.

It would make developers (or anyone doing a job for someone else) lives substantially easier if people behaved the way you think they should, but the reality is that 99% of the time they aren't doing something that most people would consider to be lying, they're just being people.

This is an opportunity to exercise some social nuance. To them, "MySQL" and "database" are equivalent, and to point out the difference is to make the social faux-pas of overspecification (somewhat of a trope for nerds like us).

By the time you're having this conversation with a BA, the DB is not going to be changed because they made some offhand reference to a different DB. They said something technically wrong, but in a way that doesn't have any meaningful effect on what they were trying to say: as such, to nitpick a detail like that may give the impression of trying to reinforce your superiority by pointing out tiny technical mistakes in their speech. So just let it go :)

Sometimes they are trying to deceive people though: Not about the spec, but about their own certitude and level of technical expertise.

The skill of going from potentially "wrong" requirements from non-experts into something engineers can deliver is one of the most important skills I've seen in technical sales people.

Customers have a problem to solve, and try to ask for something to solve that problem. Understanding the problem and proposing a solution (and a price) is how you get happy customers.

https://youtu.be/BKorP55Aqvg is a great example of how to fail at this. The "expert" totally fails to understand the customers needs, and instead gets hung up on bad definitions. He's supposed to be the expert in drawing lines, so he should be able to understand why they need them. You could say the customer is lying about their requirements, but they probably just don't understand them.

This goes for any customer/provider relationship - internal services, it departments, platform enginners. Not just selling stuff to other companies.

> You could say the customer is lying about their requirements, but they probably just don't understand them.

To build on the example from https://news.ycombinator.com/item?id=12428337: If another person says "MySQL" it is MySQL and nothing else. If they meant something different, he would say "data store" or give some non-technical description from which a technology-minded person can reconstruct what the person really wants. The same holds for the "submit button". If the person talks about a "submit button", such a button is meant. If he means something else, he would give a description, say "a user interface element which allows to send the data that I have inputted to the central data store such that [...] Choose the technology which is best according the current UI/UX guidelines.".

If I don't know what I want I give the information in a high-level way such that an expert can reconstruct/build the missing details. If I say some concrete technology that is an exact specification. If this is not what you want, it is lying. There is no in-between.

Lying is when you relate something you know to be untrue. What you're describing is more like "confusion".

Or maybe you don't know exactly what you want so you give examples demonstrating the salient features instead.

I don't think it's a great example, because with a little creativity that "impossible" spec is possible:

https://www.youtube.com/watch?v=B7MIJP90biM

The customers might even be happy with it, because it would mean they wouldn't have to admit their requirements were stupid.

> because it would mean they wouldn't have to admit their requirements were stupid

I personally prefer it to be instructed when my requirements are stupid (if there really is strong evidence that they are) since this way I can learn in a much faster pace to make good requirements.

> Behavioural driven development (BDD)

https://cucumber.io/

is a particularly awesome idea for specifying behavior. really want to try it out for a project sometime: the idea is to write the spec in these domain-specific "gherkin" files.

i find it comparatively difficult to get get buy-in on collaborating on anything machine-readable, however, unless it's from people who are comfortable with general-purpose programming languages, anyway.

nonetheless, in an industry where it's fairly standard for designers to build in domain-specific languages, i don't think it's an unreasonable skill for product managers to consider acquiring.

any user experience stories from cucumber, etc. on rewrites or otherwise?

In my experience it's a joke. It's a way for devs to write executable document strings for the tests they also write.

Absolutely no business person who is responsible at the level BDD works (the head of marketing for example) ever ever ever writes a working BDD description or frankly bothers reading them.

Maybe just maybe they are useful intermediaries for Business analysts but most of those have been fired.

Fitnese tests have more traction but then this is just exposing your API for user tests

This is my experience as well. Cucumber and the like sound like a way to get 'the business' involved more, but in practice the cucumber files just become yet another thing that the developers or testers have to write. At which point you are better off with more traditional testing methods.

> the cucumber files just become yet another thing that the developers or testers have to write

yep, if (and it's sounding more and more like "when," even outside of my anecdotal experience) that decision is made, there's not much point in using cucumber or similar.

i was kind of hoping someone would say, "yea, our product manager writes domain-specific specification files, and the workflow is so much easier!" ... but no, i'll just continue being mildly cynical a/b the role of developers in industry.

This matches my experience. I used to somewhat blame the business folks for being too lazy and/or pompous to bother with their side of the bargain, but I've come to think it's just generally a solution to the wrong problem. The hard part is correctly translating from what is asked for to what is implemented, and executable requirements don't have anything to say about that step. In cucumber, I can take any arbitrary Given / When / Then statement and implement it in any way, including ways that are completely wrong and (worse) ways that are subtly wrong. The translation code just becomes yet more code that may or may not be correct, and in my experience, it can be a lot of code. When you find yourself wanting to write unit tests for your acceptance test pseudo-english translation layer code, you're deep in a rabbit hole.

i think this (the parent post) is truth: i've had conversations a/b behavior specification where edge cases simply aren't taken into account. so the specification would say, for example

"it does this when anyone clicks a button."

whereas there's often some implicit question, like

"what happens when two people click the button at the same time?"

and that kind of concern -- where the logical implications of requirements -- is not always handled by top-down requirements management... i'm almost certain i saw a fowler article on "conversational" requirements management recently, and that made a lot of sense.

In general, BAs should not be writing the stories, but they should be able to read them together with the developers.

I find that it helps, but it doesn't solve the whole problem. The most useful bit is the stories with examples, as those are what are so often missing from specs.

The problem with edge cases is that they are infinite. If there's an edge case that's likely to happen (ideally based on evidence of past behaviour), then it can either be in the spec or just in functional tests.

I like to think that BDD is like writing the documentation first. Would you put the edge case in the documentation? If not, it probably isn't the BA's responsibility to decide what should happen, and it shouldn't have a Gherkin-style story.

But it's not a silver bullet. It's a tool that helps solve some problems on some projects in some teams. Usually, it helps in cases where the domain experts are not very technical and where the domain problem is a fairly simple set of business rules.

I'm more of a PHP developer, so I use Behat instead of Cucumber. However:

1. The value of BDD is that you have some stories with examples written in the language of end users. You can use a tool like Behat or Cucumber that parses those stories and runs them as automated tests, but it's not fundamental, and you shouldn't avoid using BDD just because the automation aspect is too difficult.

2. Avoid using Behat to interact with the browser, make HTTP calls or run command line scripts. Otherwise your features become too tightly coupled with your views. Use Behat to test your services and domain entities directly, and not to test the framework, because testing the whole application (including the framework, if you're using one) is slow and wasteful. If you want to automate the browser, there are better/faster options than Cucumber and Behat.

3. BDD features are not the same as functional tests. Your features should focus on the typical use cases and read like end-user documentation, while your functional tests should include edge cases and should be optimised for developers.

Negative experience here: someone tried to use it as a silver bullet and it made underlying problems worse.

Our "tests" are all written by "tell me what to click" QA, and the Behat source is literally commented-out because they cannot be run by programs, only the QA who made them.

mysql isn't a great example because that frequently comes up specifically because they have db analysts with skills in that system, its where the rest of their data is, already have support contracts for it, etc.

While that might be a valid reason to require MySQL as a database, it's probably not a requirement of a given form. It might not even be necessary to have a database at all - it's important to understand 'why' the BAs are saying this, and not take their opinions as the definitive solution.

For example, the ticket might look like "When I submit the form, then the DB Analysts are able to run reports on the submitted data".

The decision about what database to use still isn't a business requirement in that case though, more of a nonfunctional requirement that can be determined outside of a particular feature.

It very much is. If you told them you might decide not to use mysql so it would be completely incompatible with all of the data storage requirements, they would rightly tell you to get out for wasting their time. Your refusal to use the correct storage could cost them thousands of hours of labor establishing new processes for backups, BI integration, high availability, and just training on managing the system.

I have worked with many companies where this was a very hard business requirement. Companies that dont care how the data is stored tend to be pretty small or not actually care that much about the data.

"And I need you to write it in PHP because it's cheaper"

(not hating on modern PHP, just its reputation and 'outsourceability')

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