Presentation at Cancer Research UK Engineering Away Day, July 2019

1. Going serverless at
Comic Relief
Cancer Research UK Engineering Away Day
July 2019
Peter Vanhee, Head of Technology, Digital & Innovation

3. We’ve raised over £ 1 billion since we
started out in 1985 & organise two main
campaigns: Sport Relief and
Red Nose Day

10. 2016
Drupal 7 monolith
- Static content
- Pay-in fundraising
- Gift aid declaration
- Fundraiser gallery
- Contact us
Giving
Pages
Donate

11. 2017
Drupal 7
monolith
- Static content
- Contact us
Drupal 8
- Static content
Pay-in
fund-
raising
SMS
Gift aid
Fundraise
gallery
Giving
Pages
Donate

12. 2018
Drupal 8
- Static content
Pay-in
fund-
raising
SMS
Gift aid
Giving
Pages
Donate
Contact
us
Red Nose
Comp
School
step calc

13. 2018
Drupal 8
- Static content
Pay-in
fund-
raising
SMS
Gift aid
Contact
us
Giving
Pages
Donate
Red Nose
Comp
School
step calc
Mailer Service
Postcode lookup
Payment Service
Layer

14. 2019
Drupal 8
- Static content
Pay-in
fund-
raising
Contact
us
Payment Service layer
Image uploader service
Marketing preferences service
Mailer Service
Postcode lookup service
SMS Gift
Aid
Donate

15. Serverless costs nothing if
nobody is using it

16. DEALING WITH
UNPREDICTABILITY
Spikes in traffic and
donations are mostly
driven by broadcast
moments on the BBC.

17. DEALING WITH
UNPREDICTABILITY
Traditional hosting
solutions require
scale for your “best-
case” response rate.4 WEEKS

18. DEALING WITH
UNPREDICTABILITY
“Best-case” hosting
approach leads to
over scaling and a lot
of waste.4 HOURS

19. Scale on demand and
only pay for what you
use.
SERVERLESS COMPUTING

20. March 2019 cost*
$5,393
March 2015 cost*
$83,908
*All hosting costs are paid for through corporate partnerships.
100% of public donations go to the projects we fund.
OLD VS NEW

21. WE COULD DO
IT ALL AGAIN TOMORROW
Serverless services cost
$92

23. SCALING CHALLENGES
350
DONATIONS PER
SECOND

24. donation.comicrelief.com

25. Understand limitations of each
of your components

26. Building Blocks

27. 3rd Party Dependencies

28. bit.ly/cr-donate-blueprint

30. Feature Pipelines Production pipelines
•Improve pace of building
new features
•Catch errors and issues
before they block your
production pipeline
•Opportunities to review &
discuss with the rest of the
business
•Prototyping
•Deploy continuously to
production
•Full blown automated
testing suite

32. Traditional Testing Pyramid

33. Serverless Testing Pyramid
unit tests
Integration tests
end-to-end tests
crash reporting

44. Alerting, when..
•… warnings or errors happen in production (Sentry)
•… scheduled tests fail (Concourse)
•… user-facing lambdas > 5 seconds (IOPipe)
•… lambdas are being throttled (CloudWatch)
•… application health checks fail (Wormly)

47. Chaos engineering
deliberately practice at
being wrong
@russmiles

48. If you know your system is going to go
down, you’re not doing chaos
engineering, you’re being irresponsible
@theburningmonk

49. https://github.com/Nordstrom/serverless-artillery
Serverless Load testing

52. • Identify limiting factors

53. • Identify limiting factors
• Utilise rapid reusability

54. • Identify limiting factors
• Utilise rapid reusability
• Monitor to optimize

55. • Identify limiting factors
• Utilise rapid reusability
• Monitor to optimize
• Use Serverless load
testing

56. 2020
Contact
us
Payment Service layer
Image uploader service
Marketing preferences service
Mailer Service
Postcode lookup service
SMS Gift
Aid
Donate &
Pay in
Content
Hub
cr.comData
Platforms

57. We couldn’t have done it without…
Inquisitive
engineers
Great tech
partners
Trust from
organisation

58. Thank You!
@pvhee
github.com/comicrelief
medium.com/comic-relief