Link
Embed
Share
Beginning
This slide
Copy link URL
Copy link URL
Copy iframe embed code
Copy iframe embed code
Copy javascript embed code
Copy javascript embed code
Share
Tweet
Share
Tweet
Slide 1
Slide 1 text
Software systems have emergent structures.
Slide 2
Slide 2 text
Software systems are irregular.
Slide 3
Slide 3 text
Software systems are contextual.
Slide 4
Slide 4 text
Software systems are intricate.
Slide 5
Slide 5 text
text
Slide 6
Slide 6 text
This is a real software system.
Slide 7
Slide 7 text
It is irregular.
Slide 8
Slide 8 text
It is contextual.
Slide 9
Slide 9 text
It is intricate.
Slide 10
Slide 10 text
Its structure emerges out all its tiny details.
Slide 11
Slide 11 text
This is another real software system.
Slide 12
Slide 12 text
It is irregular.
Slide 13
Slide 13 text
It is contextual.
Slide 14
Slide 14 text
It is intricate.
Slide 15
Slide 15 text
These two systems come from different domains.
Slide 16
Slide 16 text
And they have radically different shapes.
Slide 17
Slide 17 text
But, why do they look so different?
Slide 18
Slide 18 text
Is it only because they come from different domains?
Slide 19
Slide 19 text
Let’s take a step back.
Slide 20
Slide 20 text
This visualization shows one class, its methods and its attributes.
Slide 21
Slide 21 text
The class exhibits a rather regular shape.
Slide 22
Slide 22 text
Add some collaborator classes to the mix, and its shape changes.
Slide 23
Slide 23 text
Some of it seems to want to be in a different place.
Slide 24
Slide 24 text
Add some more, and the shape shifts even more.
Slide 25
Slide 25 text
Look at the whole system, and the class is unrecognizable.
Slide 26
Slide 26 text
Look at the whole system, and the class is unrecognizable.
Slide 27
Slide 27 text
This is a tiny system.
Slide 28
Slide 28 text
This system is actually the result of only a few man-weeks of work.
Slide 29
Slide 29 text
This system is also the result of a few man-weeks of work.
Slide 30
Slide 30 text
In fact, both systems have similar functionality.
Slide 31
Slide 31 text
Yet, they have radically different shapes.
Slide 32
Slide 32 text
These three systems also have similar functionality.
Slide 33
Slide 33 text
And these two systems have similar functionality, too.
Slide 34
Slide 34 text
Yet, they have radically different shapes.
Slide 35
Slide 35 text
Why is it that even functionally similar systems look so different?
Slide 36
Slide 36 text
Because software systems are irregular.
Slide 37
Slide 37 text
Software systems are contextual.
Slide 38
Slide 38 text
Software systems are intricate.
Slide 39
Slide 39 text
Software systems have emergent structures.
Slide 40
Slide 40 text
The structure emerges out of tiny independent commits.
Slide 41
Slide 41 text
The structure emerges out of changes in requirements.
Slide 42
Slide 42 text
The structure emerges out of human interaction.
Slide 43
Slide 43 text
Software systems have emergent structures.
Slide 44
Slide 44 text
Treat software systems for what they are.
Slide 45
Slide 45 text
Upfront control is unlikely to work.
Slide 46
Slide 46 text
Embrace their emergent nature.
Slide 47
Slide 47 text
humane-assessment.com
Slide 48
Slide 48 text
Tudor Gîrba www.tudorgirba.com creativecommons.org/licenses/by-nc-sa/3.0/