frozenrails2011

@josephwilk

Tuesday, 20 September 11

Joseph WilkTuesday, 20 September 11

Limited Red


Limited RedOh crap


Work In Progress


Context Switching is Expensive


Small Batch sizes

Large batches

Small batches


Red == Work in Progress


1 day

1.5 day

2 day


Why is Red Bad?


Limit Red

Measure Red

Learn

Visualise Red


Are we Professionals?


Joseph Wilk

REFACTORING

TESTINGRE

D TI

MEPAIRING


Measuring &Visualising Red


Limited RedLearn and adapt from test metrics


Industrial Logic


Industrial LogicTuesday, 20 September 11

Fighting Red


‣Parallel Change

‣Narrowed Change

‣Sequence Change

‣Graceful Retreat

‣Piecemeal Change

‣Gradual Change

‣Evolved Target

‣Unified MethodsJoshua Kerievsky

Patterns


Parallel Change

class ImageResizer

def resize(x,y) ... end

end


Parallel Change

class ImageResizer include ThumbResizerend

module ThumbResizer def resize(x,y) ... endend


Ship it


But....


Ship itTuesday, 20 September 11

Parallel Changeclass ImageResizer if FeatureFlipper.active?(:fast_resizer) include FastThumbResizer else include ThumbResizer endend

module ThumbResizer def resize(x,y) ... endend

module FastThumbResizer def resize(x,y) ... endend


But... Bothversions!!!


Parallel Change

class ImageResizer include FastThumbResizerend

module FastThumbResizer def resize(x,y) ... endend


<%- if @game.player?(@active_user) && @black_player.present? && @white_player.present? %> <%= render :template => 'messaging' %><%- end %>

<%- if @game.player?(@active_user) && @black_player.present? && @white_player.present? %> <%= render :template => 'messaging' %><%- end %>

Narrowed Change


Narrowed Change

class GamePresenter def initialize(game, black_payer, white_player) @game, @black_player, @white_player = game, black_player, white_player end

def show_messaging?(&block) messaging_should_be_visible = @game.player?(@user) && @black_player.present? && @white_player.present? yield block if messaging_should_be_visible endend

<%- game_presenter.show_messaging? do %> <%= render :template => 'messaging' %><%- end %>


Narrowed Change

class GamePresenter def initialize(game, black_payer, white_player) @game, @black_player, @white_player = game, black_player, white_player end

def show_messaging?(&block) messaging_should_be_visible= @game.human_player?(@user) yield block if messaging_should_be_visible endend

<%- game_presenter.show_messaging? do %> <%= render :template => 'messaging' %><%- end %>


Sequence Change

Narrowed change

Remove control flag

Extract method


Graceful Retreat

Shave?

Please step away from the Yak... Slowly


http://www.refactoring.com/catalog/index.html




Learning more from Red

‣ Smart Continuous integration

‣ Failure rate

‣ Performance

‣ Flickering


Evil hat


More Books!


“To measure is to know”Lord Kelvin


@josephwilk

[email protected]

Kiitos


mailto:[email protected]


@josephwilk

[email protected]

Kiitos

Green




@josephwilk

[email protected]

Kiitos

GreenShip itTuesday, 20 September 11





frozenrails2011

Business

kiitos josephwilk joe josephwilk

messaging should be visible end endtuesday

end endtuesday

net greentuesday

ship ittuesday

industrial logictuesday

yield block

white player game