Upgrade to Pro — share decks privately, control downloads, hide ads and more …

How to write like Cats

Sponsored · Ship Features Fearlessly Turn features on and off without deploys. Used by thousands of Ruby developers. →
Avatar for Shannon Shannon
August 28, 2019
Technology
260
0

How to write like Cats

Avatar for Shannon

Shannon

August 28, 2019

More Decks by Shannon

See All by Shannon
Signify Bootcamp
Avatar for Shannon signify
0
290
Event Sourcing Blockchains at TokenAnalyst
Avatar for Shannon signify
0
150
The Last Frontier and Beyond
Avatar for Shannon signify
0
150
Jon Pither
Avatar for Shannon signify
0
250
Kubernetes as a Streaming Data Platform with Kafka, Spark, and Scala
Avatar for Shannon signify
0
100
Writing human readable tests using Scala
Avatar for Shannon signify
0
160
Making Contracts Smart, Secure and Functional with DAML and Scala
Avatar for Shannon signify
0
140
Ansible and Scala Projects
Avatar for Shannon signify
0
290
Automatic differentiation in Scala by Xiayun Sun
Avatar for Shannon signify
0
420

Other Decks in Technology

See All in Technology
なぜSRE・セキュリティは評価されないのか？守りの組織を事業成長エンジンに変えた実践
Avatar for サイバーセキュリティクラウド cscengineer
PRO
3
2.2k
grill-me（grilling）：AI駆動開発を超助けてくれるSkill / grill me
Avatar for 数理の弾丸 mathbullet
0
100
PM領域でのAI Agentの活用
Avatar for LINEヤフーTech (LY Corporation Tech) lycorptech_jp
PRO
0
270
作り直せるコードは迅速に 作り直せないDBは慎重に - AI時代のプロダクトエンジニアが「判断の不可逆性」で開発速度を変える話
Avatar for kinosuke01 kinosuke01
0
230
20260903 Tokyo Jazug Night #62 | Azure エンジニアよ、 その環境は本当にセキュアか？
Avatar for Olivia olivia_0707
1
610
AI時代のAPI品質を支えるガードレール / API Guardrails for API quality in the AI ​​era
Avatar for Yoichi Kawasaki yokawasa
1
110
スクラムで身についていた動き方を、XPで捉え直してみた
Avatar for コドモン開発チーム codmoninc
PRO
1
200
Self Healing Rollouts: Automating Production Fixes with Agentic AI
Avatar for Kevin Dubois kdubois
0
150
プロダクト思考 × 基盤思考を AIで実現する Compound Engineering
Avatar for Watanabe Takeshi(Buzz) tkc66buzz
1
260
AI活用の現在地、 ちゃんと見えてますか？/XPfest-2026
Avatar for Visional Engineering ＆ Design visional_engineering_and_design
0
150
その指示、Bobにしっかり伝わってる？初心者でも即実践できる プロンプト/コンテキスト設計のコツ
Avatar for mu (Mizuho Uehara) muehara
0
130
AIで実装は速くなった。なのにプロダクトは速くならない。職能の壁を越えて価値のフローを設計する
Avatar for nwiizo nwiizo
6
7k

Featured

See All Featured
Effective software design: The role of men in debugging patriarchy in IT @ Voxxed Days AMS
Avatar for Kenny Baas-Schwegler baasie
0
510
Making Projects Easy
Avatar for Brett Harned brettharned
120
6.7k
Build The Right Thing And Hit Your Dates
Avatar for Maggie C. maggiecrowley
39
3.4k
Leveraging LLMs for student feedback in introductory data science courses - posit::conf(2025)
Avatar for Mine Cetinkaya-Rundel minecr
1
370
Mozcon NYC 2025: Stop Losing SEO Traffic
Avatar for Sam Torres samtorres
1
520
Intergalactic Javascript Robots from Outer Space
Avatar for Vicent Martí tanoku
273
27k
The Curse of the Amulet
Avatar for Matthew Lei leimatthew05
2
14k
Building an army of robots
Avatar for Kyle Neath kneath
306
46k
GitHub's CSS Performance
Avatar for Jon Rohan jonrohan
1033
470k
Easily Structure & Communicate Ideas using Wireframe
Avatar for Afnizar Nur Ghifari afnizarnur
194
17k
Optimizing for Happiness
Avatar for Tom Preston-Werner mojombo
378
71k
Site-Speed That Sticks
Avatar for Harry Roberts csswizardry
13
1.5k

Transcript

  1. How to write like cats

  2. None

  3. What we won’t be talking about What we will be

    talking about • Category theory • Monads, Monoids, Functors etc. • Effect types • Polymorphism • Type classes • Implicits

  4. Subtype polymorphism

  5. Subtype polymorphism ↓ Ad-hoc Polymorphism (Type classes)

  6. None

  7. Live coding! github.com/MontyWest/tech-talk-typeclass

  8. Type Classes • Can add functionality to types you don’t

    ‘own’. • Can change functionality in different scopes. • Higher level of abstraction, composability and applicability. • Enables library like Cats, allows others to do your work for you!

  9. Links to follow • Typelevel Cats: https://typelevel.org/cats/ • Typelevel blog:

    https://typelevel.org/cats/typeclasses.html • Talks: ◦ Petra Bierleutgeb, Polymorphism in Scala: https://www.youtube.com/watch?v=-SA1Ui283Qc ◦ Rob Norris, ScalaX keynote: https://skillsmatter.com/skillscasts/11626-keynote- pushing-types-and-gazing-at-the-stars

  10. Thanks for listening! Any Questions?