How & When to Feature Flag

When Feature Flags

go Bad

Edith Harbaugh

CEO & Cofounder

@Edith_H

#softwareseatbelt@Edith_H

About me Cofounder & CEO, LaunchDarkly

Podcast cohost, “To Be Continuous”

InfoQ, ReadWrite, DZone contributing author

BS Engineering Harvey Mudd College

Engineering, Epicentric & Vignette

Product, Monster.com, EasyBloom, Tripit

IN THE LAST 10 YEARS, THE AVERAGE TIME TO RELEASE

AN APPLICATION HAS GONE FROM YEARS TO WEEKS

OLD WORLD

18 MONTH RELEASE CYCLE

NEW WORLD

WEEKLY RELEASE CYCLE

@Edith_H #softwareseatbelt

Feature flags have become a critical part of how we roll out

features, get feedback, and allow engineering and marketing

to proceed on their own schedules.

It’s hard to imagine DevOps services without them! - Microsoft Engineering Leadership

@Edith_H #softwareseatbelt

With LaunchDarkly we ship small changes very often.

It makes it very easy to roll back a particular change, or even

better: fix and roll-forward, and it helps us iterate very fast. - DevOps 101, Atlassian

@Edith_H #softwareseatbelt

Feature Kill Switches

for unexpected events

#softwareseatbelt@Edith_H

#softwareseatbelt@Edith_H

Controlled

rollouts

8

Early access betas for your

best guinea pigs

best customers

#softwareseatbelt@Edith_H

9

THE

CHASM#softwareseatbelt@Edith_H

Chasm larger than it appears

10 @edith_h

NONE SHALL PASS

@Edith_H #softwareseatbelt

#softwareseatbelt@Edith_H

How to flag… poorly

Ambiguously named flags

@Edith_H

Surely you

can’t be

serious?

I am

serious… and

don’t call me

Shirley!

#softwareseatbelt

I am serious…

and don’t call

me Shirley!

#softwareseatbelt@Edith_H

Overused

flags

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Conflicting

flags

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Feature

flag!

#softwareseatbelt@Edith_H

Recipe for effective feature flag-driven

development

#softwareseatbelt@Edith_H

Flag

carefully

Lock down

accessRemove

flags

launchdarkly.com

LET’S TALK

Slides, T-Shirts & more at

#softwareseatbelt@Edith_H