When Feature Flags Go Bad:How Not to Have Feature Flags Be Used Incorrectly for Disastrous Results - Edith Harbaugh, LaunchDarkly - Feature flags are a continuous delivery best practice to get feedback faster, with less risk. With feature flags, engineering changes are pushed live to production “off”, and then turned on to different users, separating deployment from release. Learn how Behalf and CircleCI to use feature flags for opt-in early access, private beta, canary releases and dark launches.

1. When Feature Flags
go Bad
#softwareseatbelt
Edith Harbaugh
CEO & Cofounder
@Edith_H

2. #softwareseatbelt@Edith_H
About me Cofounder & CEO, LaunchDarkly
Podcast cohost, “To Be Continuous”
InfoQ, ReadWrite, DZone contributing author
BS Engineering Marvey Mudd College
Engineering, Epicentric & Vignette
Product, Monster.com, EasyBloom, Tripit

3. 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

4. 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

5. 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

6. Feature Kill Switches
for unexpected events
#softwareseatbelt@Edith_H

7. #softwareseatbelt@Edith_H
Controlled
rollouts

8. 8
Early access betas for your
best guinea pigs
best customers
#softwareseatbelt@Edith_H

9. 9
THE
CHASM
#softwareseatbelt@Edith_H
Chasm larger than it appears

10. 10 @edith_h
NONE SHALL PASS
@Edith_H #softwareseatbelt

11. #softwareseatbelt@Edith_H
How to flag… poorly

12. 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!

13. #softwareseatbelt@Edith_H
Overused
flags

14. #softwareseatbelt@Edith_H
Conflicting
flags

15. #softwareseatbelt@Edith_H
Feature
flag!

16. #softwareseatbelt@Edith_H

17. Recipe for effective feature flag driven
development
#softwareseatbelt@Edith_H
Flag
carefully
Lock down
access
Remove
flags

18. launchdarkly.com/gluecon
LET’S TALK
Slides, T-Shirts & more at
#softwareseatbelt@Edith_H