Ruby for complete beginners

https://rubyconf.africa/speakers/okura-masafumi/

Transcript

1. Ruby for complete beginners RubyConf Africa 2026, Keynote OKURA Masafumi, 2026-08-22
2. Jambo!
3. Jina langu ni Masafumi
8. 3 2019 2024 2026
10. 3 important questions • What is programming? • How can we get better at programming? • Why is Ruby good for beginners?
11. self.introduction • Name: OKURA Masafumi (Masafumi is my rst name) • Title: Freelance software developer • Works/Activities: Authoring Alba gem (JSON serializer), founding of Kaigi on Rails (a Rails conference in Tokyo) • Likes: Coffee, joining conferences (RubyConf Africa is the 7th Ruby fi conference I’ve attended this year so far)
18. What is programming? 1. 2. 3. What is programming? How can we get better at programming? Why is Ruby good for beginners?
19. What is programming?
20. Writing code?
21. ❌Writing code
22. ⭕Making abstract things more concrete
23. Abstract / Essential / Valuable • Ideas • Intentions • Thoughts • Businesses • Logics
24. Concrete / Non-essential / Less-valuable • Implementations • Code • Classes • Functions • Documents
25. Example: Anagram check
28. e.g. anagram check Abstract • We want to check if two words are anagrams or not Concrete • Strip each word, make each word down case, sort each word and check if they are equal
29. Another example: e-commerce website
30. e.g. What E-commerce sites do? Abstract • We want to sell things • Payment system • We want to communicate with • Noti cations system customers • We want to store customer data fi Concrete • Database for customers storing name, address, etc.
31. e.g. What E-commerce sites do? Still Abstract • Payment system • Stripe and its client library • Noti cations system • Email delivery with Sendgrid • Database for customers storing • PostgreSQL server with a name, address, etc. fi More Concrete schema
32. Making abstract things more concrete
33. Why?
34. Computers can do concrete things only
35. Human interaction Application Library OS / Middleware Hardware
36. Gradual translation
37. Human interaction Application Library OS / Middleware Hardware
38. Abstraction
39. Human interaction Rails Application Rails, pg gem Linux, Ruby, Postgres CPU
40. Why?
41. Humans are better at abstract things
42. Programming is translation between humans and computers
43. How can we get better at programming? 1. 2. 3. What is programming? How can we get better at programming? Why is Ruby good for beginners?
44. How can we get better at programming?
46. I’m a translator 😏
47. How can we get better at translation?
48. Japanese: 🤩 English: 😎 Vim/Neovim: 💪
49. Being good enough at 3 things
50. • Target language • Original language • Vim/Neovim
51. • Computer language • Human language • Problem domain
52. English Japanese
53. English Intermediate ideas Japanese
54. Understanding
55. English Understanding Intermediate ideas Japanese
56. English + Vim/Neovim Understanding Intermediate ideas Japanese
57. English + Vim/Neovim Understanding Intermediate ideas Expressiveness Japanese
58. Expressiveness
59. Problem domain expressed in human language Understanding Intermediate ideas Expressiveness Software product
60. Being expressive with computer language
61. Being expressive with Ruby
62. How can we get better at programming? • Understanding things well • Being familiar with problem domain • Being expressive • Being familiar with computer languages
63. Why is Ruby good for beginners? 1. 2. 3. What is programming? How can we get better at programming? Why is Ruby good for beginners?
64. Ruby for complete beginners RubyConf Africa 2026 OKURA Masafumi, 2026-08-22
65. Ruby for complete beginners RubyConf Africa 2026 OKURA Masafumi, 2026-08-22
66. Why is Ruby good for beginners?
67. Understanding
68. How do we understand something?
69. Trials and errors
70. ❌0 -> 100 ⭕0 -> 10 -> 20… 100
71. How do we understand the problem?
72. Trials and errors
73. Gradual understanding
74. How can we gradually program?
75. Exploratory Programming
76. New concept: Exploratory Programming 1. Write code to solve problems (which might be real problems) 2. Understanding problems better by observing code and its behavior 3. Go back to 1 until we are sure we understand problems well enough
77. The goal is not code
78. The goal is understanding
79. Why is Ruby good at Exploratory Programming?
80. fi Example: Anagram nder
88. Ruby’s strengths • Powerful stdlib: `combination`, `group_by`, `strip`, etc. When you need it, there it is. • Powerful ecosystem: Rails offers even more vocabularies. It extends builtin classes so it feels natural as if it existed from the beginning. • Powerful expressiveness: It expresses what it does, not how it does. With method chains, it reads as English.
89. Another example: Alba
94. Ruby is a framework for thinking
95. Ruby is a framework for understanding
96. Ruby is a framework for expressing
97. Let’s build things with Ruby
98. Let’s build things with Ruby so that we are better programmers