A talk presented at the London Web meetup on 21st July 2011.

1. Lanyrd.com
How we bootstrapped Lanyrd
using Twitter’s social graph
Simon Willison @simonw

2. Lanyrd.com
Definitive database
of professional events
and speakers

3. Lanyrd.com
Definitive database Social event recommendation
of professional events Comprehensive speaker profiles
and speakers Archive of slides, notes and video

4. Lanyrd.com
Demo

5. Lanyrd.com
Why does it work?
•The right crowdsourcing incentives
•Wiki-style shared ownership
•The parts support the whole
•Twitter!

6. Lanyrd.com
Why Twitter?
•It’s where the event discussion happens
•Speakers promote their Twitter accounts
•Follow beats Friend for recommendations
•Culturally amenable to public profiles

7. Lanyrd.com
Bootstrapping
•Classic social software challenge
•Our secret weapon: the speakers!
•Twitter accounts are public identifiers
•(and speakers have lots of followers)
•500 profiles before launching our beta

8. Lanyrd.com
More demos

9. Lanyrd.com
Key Twitter APIs

10. Lanyrd.com
friends/ids.json
[43593, 19972629, 778518,
1249881, 70478255, 3829151,
350373, 12161, 13141, 751953,
22785347, 2633711, 14835908,
143883, 14159138, 11963132,
14917418, 15732699,
756475, ...]

11. Lanyrd.com
friendships/create

12. Lanyrd.com
users/search.json

13. Lanyrd.com
Under the hood

14. Lanyrd.com

15. Lanyrd.com
Secret weapon #1: Redis

16. Lanyrd.com
Secret weapon #2: Solr

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Redis set intersection

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Calendar
•Pull user’s friends/ids.json
•Cache for ten hours
•Store in Redis
•Solr search: attendees:(34722 OR 1312313 OR...

19. Lanyrd.com
Pros and cons

20. Lanyrd.com
Pros
•One-click signup
•Naturally viral
•Instant personalisation
•Pre-created profiles, ready to be claimed
•APIs are pleasant to work with

21. Lanyrd.com
Cons
•One big, scary dependency
•No namespace control
•Hard to optimise, as no local graph copy
•Some users follow/are-followed a LOT
•OAuth permissions...

22. Lanyrd.com
Permissions hell

23. Lanyrd.com
Tweet this:
@lanyrd attending
#londonweb
lanyrd.com/adthp