“Why Swift?” for everyone else & so much more

Talk given at NSSpain on 18 September 2015

The Venmo iOS team has spent the past 8 weeks rewriting our entire app (full of crufty old code dating back to 2011) in Swift. There were a lot of great things that we got out of this, but one of the biggest questions that we get is “That’s awesome, but how do I convince the rest of my team/company/stakeholders that it’s worth it?” This talk will cover subtle techniques and pitfalls to avoid to get what you want and how to apply it to other situations like giving code review feedback and working as a team in general.

Transcript

1. WHY Swift? FOR EVERYONE ELSE & SO MUCH MORE NSSPAIN 2015 !
2. Hi! I’m Ayaka. @AYANONAGON
4. WE REWROTE OUR ENTIRE APP IN SWIFT.
5. ▸ 8 weeks ▸ 5 iOS Engineers
6. VENMO-IOS-CLASSIC ▸ > 66,000 lines of Objective-C ▸ 2011
9. VENMO ▸ 16,000 lines of Swift 2.0 ▸ A lot of new frameworks, like VenmoKit, ContactsKit, and Static
10. WHY Swift? FOR EVERYONE ELSE & SO MUCH MORE NSSPAIN 2015 !
11. How do I get what I want?
12. CONTINUOUS INTEGRATION
13. ACCESSIBILITY
14. WATCHOS 2 APP
15. Why?
16. Why DO WE WANT TO WRITE Swift IN THE FIRST PLACE?
17. MORE PREDICTABLE AND SAFER ▸ Type-safety ▸ Immutability & strict compiler ▸ Nicer syntax
18. ABSyncOperation.m
19. Thou shall not touch ABSyncOperation.
20. THIS WOULDN’T EVEN HAPPEN IN Swift BECAUSE IT CAN’T!
21. MORE ENJOYABLE AND FASTER TO WRITE
22. LYFT’S REWRITE “On the old version, that was a project that took more than a month, with multiple engineers. And with Swift, that was a project that took a week for one engineer.”
23. ATTRACT GREAT DEVELOPERS
24. Why? ▸ Write more predictable and safer code ▸ Make development more enjoyable and faster ▸ Attract great developers
25. We want to ship a great product.
26. ENGINEERING IS A means to an end
27. TIE IT TO ANOTHER PROJECT
28. Hey can we just have like 2 months to rewrite our entire app in Swift? !
29. MAKE IT INCREMENTAL
30. NON-PRODUCTION USE
31. NON-PRODUCTION USE ▸ Scripting ▸ Tests
32. 2. NEW CODE IN SWIFT
35. ▸ Bi-weekly demo ▸ Make it a part of daily conversation ▸ Less foreign !
36. 3. NOW WE WANT TO REWRITE THE ENTIRE APP IN SWIFT
37. MAKING THE CASE
38. LOGIC LOGIC LOGIC LOGIC LOGIC
39. QED
40. AIRTIGHT
41. RIDICULOUS
42. ILLOGICAL
43. ! ! ! ! ! !
44. ! “SURE...”
45. ☕ "
46. YOU MIGHT WIN
47. … BUT THEY’LL FEEL AWFUL !
48. … AND YOU’LL PROBABLY LOSE NEXT TIME !
49. ASK FOR THEIR OPINIONS
50. What if we miss something?
51. What about the other projects that are in the backlog?
52. ! " # $ %
53. FIGHT OR FLIGHT DEFENSIVE
54. OPPOSING OPINIONS ARE BASED IN SOME FACT
55. TAKE IT AS AN ✨ OPPORTUNITY ✨
56. How are we going to make sure we don’t miss anything?
57. That’s a great question. Can you help us make sure we don’t miss anything?
58. RESULT ▸ Way better QA plan for release ▸ More confidence in the rewrite and timeline ▸ Felt more like we were working together
59. The UI Changed. Can you update it?
60. !
61. !
62. That’s going to be harder to build and take a lot longer.
63. Is there a middleground that we can reach?
64. “ya, of course”
65. “What do you think?”
66. NOT YOU VS. THEM
67. LESS stress & animosity
68. MORE happiness & collaboration
69. RECAP 1. Find a shared goal 2. Make it incremental 3. “What do you think?”
70. RESOURCES ▸ Fast Company’s article on Lyft’s Swift rewrite ▸ Getting More by Stuart Diamond ▸ Stuff coming from our team soon!
71. DON’T ASK FOR PERMISSION.
72. DON’T ASK FOR TOO MUCH PERMISSION.
73. THANK YOU Gracias
74. QUESTIONS? @AYANONAGON