SLIDE 1
Patterns of Software Change
Michael Feathers Groupon
Wednesday, June 20, 2012
Architecture |ˈärkiˌtek ch ər| noun, the part of a system that you can not replace without having a different system
Wednesday, June 20, 2012
Patterns of Software Change Michael Feathers Groupon Wednesday, - - PowerPoint PPT Presentation
Patterns of Software Change Michael Feathers Groupon Wednesday, - - PowerPoint PPT Presentation
Patterns of Software Change Michael Feathers Groupon Wednesday, June 20, 2012 Architecture |rkitek ch r| noun , the part of a system that you can not replace without having a different system Wednesday, June 20, 2012 Unintentional
SLIDE 2
SLIDE 3
Unintentional Coupling is Inevitable
Wednesday, June 20, 2012
SLIDE 4
Unintentional Coupling is Inevitable
Wednesday, June 20, 2012
SLIDE 5
Class:
- Handles Tax Calculation
- Handles Charges & Discounts
Wednesday, June 20, 2012
SLIDE 6
Class:
- Handles Tax Calculation
- Handles Charges & Discounts
Someone decides taxes can be modeled as a charge
Wednesday, June 20, 2012
SLIDE 7
Validation in the Model or the Controller?
Wednesday, June 20, 2012
SLIDE 8
Organic Patterns
Designer Christopher Poehlmann
Wednesday, June 20, 2012
SLIDE 9
Piecemeal Growth Is the Hallmark of Organic Systems
Wednesday, June 20, 2012
SLIDE 10
Piecemeal Growth Biases Toward Existing Structure
Wednesday, June 20, 2012
SLIDE 11
Architecture |ˈärkiˌtek ch ər| noun, the part of a system that you can not replace without having a different system
Wednesday, June 20, 2012
SLIDE 12
The Antidote to Stagnation is Continual Renewal
Wednesday, June 20, 2012
SLIDE 13
..and appreciation for things we can’t change
Wednesday, June 20, 2012
SLIDE 14
Self-Induced Disruption
Wednesday, June 20, 2012
SLIDE 15
Card Checking a Design
Wednesday, June 20, 2012
SLIDE 16
Card Checking a Design
“What is we did this now?”
Wednesday, June 20, 2012
SLIDE 17
Wednesday, June 20, 2012
SLIDE 18
Over-Engineering |ˈōvər ˌenjəˈni(ə)ri ng| noun, weighting a possible future too highly in design
Wednesday, June 20, 2012
SLIDE 19
The Coupling Sweet Spot
Wednesday, June 20, 2012
SLIDE 20
The Coupling Sweet Spot
Single Responsibility Might Be The Closest Thing We Have, But It Is Not Perfect
Wednesday, June 20, 2012
SLIDE 21
Accidental De-coupling
Wednesday, June 20, 2012
SLIDE 22
Accidental De-coupling
The Fitnesse Story
Wednesday, June 20, 2012
SLIDE 23
When to Jump Course
Wednesday, June 20, 2012
SLIDE 24
Activity Flurries
Wednesday, June 20, 2012
SLIDE 25
Commits
Complexity
Turbulence
Wednesday, June 20, 2012
SLIDE 26
Wednesday, June 20, 2012
SLIDE 27
Wednesday, June 20, 2012
SLIDE 28
The Trending View
Wednesday, June 20, 2012
SLIDE 29
Methods Ascending
Wednesday, June 20, 2012
SLIDE 30
Trending Methods
Wednesday, June 20, 2012
SLIDE 31
Static Views
Wednesday, June 20, 2012
SLIDE 32
Classes By Closure Date
[["DummiesController", 2008-04-21 13:03:08 -0700], ["Core::ActiveRecord::AttributeDefaults::ClassMethods", 2008-04-22 16:02:54 -0700], ["Legacy::Database", 2008-04-24 15:37:51 -0700], ["Core::ActiveRecord::AttributeDelegation::ClassMethods", 2008-04-24 20:46:58 -0700], ["Core::ActiveRecord::SkipValidationForHasOnes", 2008-04-29 21:54:32 -0700]]
Wednesday, June 20, 2012
SLIDE 33
Classes By Closure Date
Wednesday, June 20, 2012
SLIDE 34
Temporal Correlation of Class Changes
[[["App", "Inventory"], 277], [["Inventory", "Object"], 216], [["Admin", "Inventory"], 195], [["Inventory", "User"], 188], [["Inventory", "Users"], 171], [["Inventory", "Deals"], 167], [["App", "Object"], 159], [["App", "InventoryController"], 152], [["Inventory", "Order"], 149], [["User", "Users"], 149], [["App", "User"], 143], [["Inventory", "InventoryController"], 143], [["Api", "Inventory"], 141], [["Admin", "App"], 136], [["Campaign", "Orders"], 134]]
Wednesday, June 20, 2012
SLIDE 35
Temporal Correlation of Class Changes
Wednesday, June 20, 2012
SLIDE 36
Objective vs. Subjective
Wednesday, June 20, 2012
SLIDE 37
Card Checking Can Reduce Metrics Bias
Wednesday, June 20, 2012
SLIDE 38
Self-Induced Disruption (2)
Wednesday, June 20, 2012
SLIDE 39
Apoptosis
Wednesday, June 20, 2012
SLIDE 40
Leveraging Conway
Wednesday, June 20, 2012
SLIDE 41
Understanding the Limits of Growth
Wednesday, June 20, 2012