steve

tyler

tyler

tyler

Definition: you make an action, observe the effect, and repeat.

steve

The canonical example of a feedback loop is a thermostat.

steve

The thermostat checks the room temperature.

If it is below the desired temperature, it tells the furnace/boiler to...

steve

And the furnace says "I'm about to"

steve

The thermostat checks the temperature again, and the loop continues

Until the temperature is a perfect 67 degrees, when it tells the furnace/boiler to stop

steve

And the furnace says "Collaborate and listen".

steve

And so this cycle continues until April

...

But not all feedback loops are equal.

steve

I am a bike guy.

When your bike starts clicking when you pedal, it often means you need to adjust your derailleurs.

steve

And this is a derailleur.

Maybe you don't recognize it by name, but you probably recognize it as the mechanical thingy

that changes the gears on your bike when you click a button on the handlebars.

steve

To tune the derailleurs on your bike, there is a feedback loop.

You turn a screw a quarter turn, and then you ride the bike 20 feet to see if everything is lined up.

steve

Bad

Here's a way to make that feedback loop awful.

The problem is, I don't see the results of this for days.

And if I get it back and find that it still doesn't shift well, I have to take it back to the shop again.

This is a loose, slow feedback loop.

steve

Better

We can make this a little better.

It turns out my neighbor knows bikes, and he knows which screw to turn 1/4 turn.

Here, I see the results of each tuning in a much shorter time.

But I still have to take my bike over to my neighbors house each cycle through the loop.

steve

Best!

But we can make this even better!

I can learn a new skill - in this case, bike repair

And now, I get to see the results of each tuning almost instantly!

steve

The tighter the loop, the quicker the feedback/your ability to react

There are a couple of ways to do this.

steve

One way is to make the arrows in the loop shorter.

steve

In my bike example, it meant eliminating trips to the bike shop or neighbors house.

Tyler

So let's take a look at a feedback loop we experience daily.

This is the loop between developers and QA.

There are a lot of stops along that loop.

A lot of opportunities for that loop to get bigger, and slower.

Tyler and I want to help you make that loop smaller, instead.

...

Here's our first suggestion.

What if we told you there was a shortcut on this loop?

Tyler

What if we told you there was a way to get changes to the developer,

without having to go through half of this loop?

Our good friend Rob has some advice for us

steve

And Tyler and i have a great way for that to happen.

steve

Tyler

Tyler

Alright we're gonna build a calculator!!! Pull up VS, take turns driving keyboard, have test and code alongside each other

Test cases/implementation direction Division has weird edge cases Tester writes the test name at the beginning Later on QE writes the test themselves Run with NCrunch or VS2017, show Code Coverage for 'slower' feedback Go for 3-5 iterations, have QE suggest edges, have dev suggest edges

Tyler

Tyler

Developers will be happy that their code is simpler

Tyler

I don't have to re-launch the app every time I make a change,

and step through 7 steps to get to the issue I'm fixing.

steve

Grocery list

steve

steve

It is a great opportunity for collaboration amongst team members

steve

All of the small, granular test cases serve as documentation of the system

steve

Because you are thinking about edge cases

as you build it

Tyler

Tyler

Any time you make a change, you are looking at it from the perspective of the user of your system.

Tyler

Which leads to better quality

And fewer regression bugs

...

You can still write bad code with TDD

But it leads you toward writing better code

(you make it harder on yourself by not writing clean code)

Tyler

Tyler

Tyler

Tyler

Tyler

Collaboration Faster feedback Better business decisions

steve

steve They are instead done in small batches, easy to handle, less change shocking the system. Also forces you to do them routinely, which forces you to streamline the process, which in turns means not doing them at midnight on Christmas.

steve Example: turbotax running experiments during tax season. Throw a thousand good/bad/ugly ideas and scientifically find the million-dollar ones.

steve

The users are the ones who actually buy our products, so they get to truly say what is high-quality. Prove that by getting feedback from them, not just from others in our company.

tyler

How is this different from before? We've taken away the shortcuts, and added customers

tyler

steve

How do I get started?

steve

steve

steve

tyler

tyler

make yourself highly approachable, encourage questions and dialogue

tyler

Even though we know it's wrong, it still hurts when our code isn't working.

Be gentle with the bug reports!

Also, TDD is hard - you can't just tell them to start doing it.

steve

steve

so the build server can actually do stuff

steve

steve

Bring this to your boss/PM/PO

talk about the potential gains in investing someone's time

steve