Symfony 3.0 focuses on backward compatibility and quality processes. It maintains the continuous upgrade path for applications to seamlessly migrate to newer versions of Symfony. Symfony 3.0 itself does not contain major new features, but rather builds upon the improvements already included in Symfony 2.8 through strict quality standards and processes. These include triggering deprecation notices, continuous integration testing, and guidelines to help third party libraries also maintain backward compatibility when upgrading their dependencies.

1. SensioLabs
Migrating
to Symfony 3.0
by @nicolasgrekas

3. Let me tell you
how Symfony 3.0
was born

4. components
framework
+=

5. Highest
quality
processes
=

6. Releasing

7. Symfony Lifecycle
Release
end of
support
+8 months +14 months +36 months +48 months
end of security
support
end of security
support
end of
support
Standard Releases
(2.4, 2.5, 2.6, 3.0)
LTS Releases
(2.3, 2.7, 2.8)

8. Semantic Versioning
http://semver.org

9. Major
Minor
Patch

10. •
o
o
o
•
o
o
•
o
o

11. One monolithic
repo.
+
46 synchronized
components
=

12. Backward
Compatibility

13. The Backward Compatibility Promise
http://symfony.com/bc

14. Guidelines for Backward Compatibility

15. Example: Moving the
FlattenException class

16. Example: Moving the
FlattenException class

17. Example: Moving the
FlattenException class

18. Example: Moving the
FlattenException class

19. Patching process

20. •
•
•
Contribution Workflow

21. Patching Symfony 2.3 LTS

22. Continuous integration

23. Travis Matrix

24. Appveyor for Windows

25. What’s new
in Symfony 3?

26. Well... Nothing!
Fabien already
told you

27. All new features are
already included in
Symfony 2.8
What’s new in Symfony 3?

28. The Symfony 3.0 Architecture
•
•
•
•
•

29. What’s new
in Symfony 3?

30. The
Continuous
Upgrade
Path

31. The Symfony Core Team Wish!

32. Continuous Migration Path Before 2.7
•
•
•
•
•
•
• 

33. Continuous Migration Path Since 2.7
•
•
•
•
•
•
•

34. Trigger deprecation notices at run-time

35. Trigger deprecation notices at run-time

36. Trigger deprecation notices at run-time

37. Trigger deprecation notices at run-time

38. Trigger deprecation notices at run-time

39. Trigger deprecation notices at run-time

40. Trigger deprecation notices at run-time

41. It has to work
for Symfony itself,
component by
component

42. Cross Versions Dependencies
•
o
o ~2.x|~3.0.0

43. The @legacy PHPUnit Group

44. Cross Versions Dependencies
•
o
o ~2.8|~3.0

45. Prefer Lowest Requirements

46. Sustainability
of the CUP promise?

47. •
•
•
•

48. What’s new
in Symfony 3?

49. Much
Stricter
Quality
Processes

50. What about the
Symfony ecosystem?

51. Use the Symfony PHPUnit Bridge

52. Allow Symfony ~3.0 Dependencies

53. Their turn to deprecate

54. Their turn to deprecate

55. What’s new
in Symfony 3?

56. A Process
to Remove
Legacy Code

57. Now your turn!

58. •
•
•
•
o
o
o
•
•
Some guidelines

59. Some guidelines

60. Some guidelines

61. Some guidelines

62. Some guidelines

63. Some guidelines

64. Some guidelines

65. Some guidelines

66. Some guidelines

67. Now your turn!

68. SensioLabs
Merci !
@nicolasgrekas