1. Simon Stewart
simons@fb.com
github.com/shs96c
@shs96c
Building Facebook for Android
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2. Mid 2012: becoming native
▪ “We were never able to get the quality that we wanted. Looking back, that’s probably
one of the biggest if not the biggest mistake [we made]”
http://www.flickr.com/photos/anandham/4499539060/
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3. Engineers committing mobile code
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4. (but there are spoons)
There is no Android team
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5. A developer’s day
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6. Build
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7. The working copy
▪ We use git for source control
▪ Two branches we care about day-to-day:
▪ master
▪ stable
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8. How the code is organized
Text
http://www.flickr.com/photos/darwinbell/3030214710/
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9. ▪ git checkout -b fancy_feature
▪ hack, hack, hack
▪ git commit -am ‘Fancy new feature’
▪ git rebase origin/stable
▪ hack, hack, hack,
▪ git commit -am ‘checkpoint’
▪ git rebase -i HEAD~2
▪ arc diff
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10. Dependency injection
http://www.flickr.com/photos/31246066@N04/5253179784/
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11. Test
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12. Developers write tests
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13. Unit tests
http://www.flickr.com/photos/aracelota/4773084433/
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14. Larger tests
http://www.flickr.com/photos/amphalon/6510474165/
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15. Commit
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16. Code review
▪ arc diff
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17. Image macros
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18. Arcanist
▪ The command line counterpart to Phabricator
▪ arc lint
▪ Runs Android’s own lint tool
▪ Checks for common errors:
▪ Null pointers
▪ Using APIs unavailable in all supported Android versions
▪ arc land
▪ Pushes code into the tree
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19. Buildbot
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20. Dogfood
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21. Gingerbread
▪ Still incredibly popular.
▪ Some employees use a Gingerbread device
▪ Including our release manager
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22. Updates
▪ Employees use more recent version of the apps
▪ Rage shake to report bugs
http://www.flickr.com/photos/raindrift/7095238893/in/set-72157629492908038
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23. Release
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24. Pick two
Features, quality, schedule
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25. Time based releases
Text
http://www.flickr.com/photos/andyhay/6947688734/
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26. “Done” isn’t just native code
▪ Design
▪ Release branch doesn’t take design changes, implies work isn’t quite ready
▪ Logging
▪ How do we know we aren’t regressing without data?
▪ Server-Side
▪ We need to test the interactions our users will see
▪ Privacy and Legal review
▪ Just as important as code review
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27. Questions?
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