Make legacy great again

How to deal with legacy code? Where to start? What is legacy code anyways? This talk was held during Behind the Scenes at Coolblue office at 27th of Oct

Transcript

1. MAKE LEGACY GREAT AGAIN. It was perfect when I wrote it!
2. DONATAS. Part of Coolblue.
3. MAKE LEGACY GREAT AGAIN. It was perfect when I wrote it!
5. OLDEST PIECE OF CODE. 2004. PHP4.
6. AGENDA.
7. NOT A SILVER BULLET.
8. EVERYTHING. is legacy.
9. DIVING INTO LEGACY.
10. ITS YOUR LEGACY.
11. CODE FOR SILENT PSYCHOPATH WHO KNOWS WHERE YOU LIVE.
12. SOLID LEGACY = GOOD LEGACY.
13. WE ARE DETECTIVES.
14. UNDERSTANDING HOW LEGACY WORKS = PATH TO WIN.
15. HALF A YEAR TO MAKE RATIONAL CHOICES.
16. 100% IS NEVER WORTH IT.
17. WRITE NEW CODE. you must
18. DON’T WRITE MORE LEGACY.
19. MINDSET IS HARDEST THING TO CHANGE.
20. SIMPLE START:
 PSR, SOLID, TESTS AFTER.
21. MIX OLD AND NEW, 
 SPREAD WIDELY.
22. WHY REPEAT THE SAME MISTAKES?
23. EMBRACE THE FAILURE.
24. BAD LEGACY ALWAYS BREAKS.
25. BETTER DETECTIVES CREATE LESS BROKEN BUILDS.
26. SECRET INGREDIENT: 
 BREAK PRODUCTION.
27. THE WHEEL. Already invented.
28. EVERYTHING IS CUSTOM IN LEGACY CODE.
29. SOLID LEGACY = GOOD LEGACY.
30. DO YOU CREATE NEW FUNCTIONALITY IN BAD LEGACY?
31. USE LIBRARIES WHICH SOLVE STANDARD PROBLEMS.
32. FOCUS ON VALUE FOR THE CUSTOMERS.
33. WHAT IS THE MOST IMPORTANT SKILL FOR DEVELOPER?
35. REFACTORING.
37. REFACTORING - IMPROVING CODE WITHOUT CHANGING BEHAVIOUR.
38. REFACTORING - AN ART FORM.
39. FAIL, READ, LEARN.
 RINSE AND REPEAT.
40. DANGER ZONE.
41. MAIN(), INIT(), LOAD(), __CALL().
42. INPUT/OUTPUT METHOD IS 
 CLEAN AND TESTABLE CODE.
43. LEAVE MESS FOR LATER, 
 BUT LESS EVERY TIME.
44. MAGIC CODE WILL EXPLODE.
 UNDO MAGIC, ADD UNIT TESTS.
45. TEMPLATES. BUSINESS LOGIC, DB CALLS, UNTESTED CALCULATIONS.
46. INTERFACE TEMPLATES FOR EASIER REFACTORING.
47. JUST DO IT. No, really, just do it!
48. AUTOMATIC REFACTORING WITH PHPSTORM.
50. QUICK & DIRTY AUTOLOAD OVERRIDE.
51. FAKE CLASSES YOU CAN’T PROPHESIZE.
52. EVERYTHING IS TESTABLE.
53. MAKE REFACTORING A HABIT.
54. HOW DID YOU IMPROVE CODE TODAY?
55. TOOLS. Automate all the things.
56. • PHP_CodeSniffer • PHPMetrics • PHPMD • PHP Depend TOOLS.
57. AWARENESS AND VISIBILITY HELPS TO IMPROVE.
58. PREVENTING BAD LEGACY.
59. REAL LIFE. Routing.
60. PROBLEM.
61. DECISION.
62. PREPARATION.
63. WORK WORK WORK 
 (WITH TDD).
64. D-DAY - SO SMOOTH.
65. GRUMPY CATS. They’re always everywhere and grumpy
66. DEVELOPERS WANT TO BUILD QUALITY CODE.
67. YOU DECIDE YOUR LEGACY.
68. CUSTOMERS DEPEND ON YOU.
69. SHARE THE BENEFITS.
 VISUALISE THE PROBLEMS.
70. GRUMPY = LOST OR ASHAMED.
 HELP THEM.
71. OUTRO. Yes, I’m finally shutting up.
72. REFACTORING IS A BIG TOPIC.
73. NOT A SILVER BULLET.
74. FAVOUR TESTED, SOLID LIBRARIES OVER CUSTOM CODE.
75. SOFTWARE IS ALIVE.
 FOCUS ON TODAY.
76. KNOWING ART OF REFACTORING
 WILL MAKE LEGACY GREAT!
77. THANK YOU. Questions?