Upgrade to Pro
— share decks privately, control downloads, hide ads and more …
Speaker Deck
Features
Speaker Deck
PRO
Sign in
Sign up for free
Search
Search
Getting Clean, Keeping Lean
Search
Joe Birch
March 17, 2017
Programming
10
670
Getting Clean, Keeping Lean
Joe Birch
March 17, 2017
Tweet
Share
More Decks by Joe Birch
See All by Joe Birch
Learning to play guitar with Actions on Google
hitherejoe
1
96
Making Change as an Ally
hitherejoe
1
460
Tensorflow for Android Developers
hitherejoe
3
250
Learning to play the guitar with Actions on Google
hitherejoe
0
130
For Optimists, our UI is pretty Pessimistic
hitherejoe
4
2.8k
Android Things: Building for the IoT
hitherejoe
2
170
Android TV: Building Apps with Google’s Leanback Library
hitherejoe
1
1k
Building Beautiful Apps with the Design Support Library
hitherejoe
3
240
Other Decks in Programming
See All in Programming
AI コーディングエージェントの時代へ:JetBrains が描く開発の未来
masaruhr
1
200
TypeScriptでDXを上げろ! Hono編
yusukebe
3
770
イベントストーミング図からコードへの変換手順 / Procedure for Converting Event Storming Diagrams to Code
nrslib
2
1.1k
AI Agent 時代のソフトウェア開発を支える AWS Cloud Development Kit (CDK)
konokenj
6
800
Startups on Rails in Past, Present and Future–Irina Nazarova, RailsConf 2025
irinanazarova
0
240
明示と暗黙 ー PHPとGoの インターフェイスの違いを知る
shimabox
2
620
dbt民主化とLLMによる開発ブースト ~ AI Readyな分析サイクルを目指して ~
yoshyum
3
1.1k
Google Agent Development Kit でLINE Botを作ってみた
ymd65536
2
260
Claude Code + Container Use と Cursor で作る ローカル並列開発環境のススメ / ccc local dev
kaelaela
12
7k
『自分のデータだけ見せたい!』を叶える──Laravel × Casbin で複雑権限をスッキリ解きほぐす 25 分
akitotsukahara
2
660
初学者でも今すぐできる、Claude Codeの生産性を10倍上げるTips
s4yuba
16
13k
iOS 26にアップデートすると実機でのHot Reloadができない?
umigishiaoi
0
140
Featured
See All Featured
KATA
mclloyd
30
14k
Designing for Performance
lara
610
69k
Testing 201, or: Great Expectations
jmmastey
43
7.6k
Put a Button on it: Removing Barriers to Going Fast.
kastner
60
3.9k
The Myth of the Modular Monolith - Day 2 Keynote - Rails World 2024
eileencodes
26
2.9k
Why Our Code Smells
bkeepers
PRO
337
57k
How GitHub (no longer) Works
holman
314
140k
Improving Core Web Vitals using Speculation Rules API
sergeychernyshev
18
990
Build The Right Thing And Hit Your Dates
maggiecrowley
37
2.8k
The Pragmatic Product Professional
lauravandoore
35
6.7k
The Illustrated Children's Guide to Kubernetes
chrisshort
48
50k
A better future with KSS
kneath
238
17k
Transcript
Getting clean. Keeping lean.
@hitherejoe hitherejoe joebirch.co Joe Birch - Android Engineer @ Buffer
@buffer buffer.com
Greenfield projects
None
- High-level of technical debt - Extremely tightly coupled concepts
- No unit or UI tests - Difficult to know what is going on and where No longer lean
- YOU know what is what - YOU know where
class X is - YOU know where logic for Y is - But what about along the line… No longer lean (for now) (for now) (for now)
25 50 75 100 Output Debt
25 50 75 100 Output Debt
For the sake of yours and future developers sanity -
have empathy. Be mindful of the consequences and think before you craft.
Buffer for Android
None
None
None
- Lack of architecture - Bloated activities with multiple responsibilities
- Difficult to test - Difficult to extend and maintain - Duplication of concepts == no reuse
Moving to MVP - Fear of changing too much -
Helped separate presentation logic - DataManagers to house data operations - Increased test coverage
None
None
Not enough. - Bloated DataManager classes - Future changes, offline
- where? - Presentation linked to specific data source - No clear line between responsibilites - Buffer is a big app. Data types, features, sources
Architecture “The art of planning, designing and constructing buildings”
Architecture “The art of planning, designing and constructing buildings concepts”
None
None
None
None
None
Think outside of your team.
Clean Architecture
None
Separation of Concerns
- Layers are independent of frameworks - Code becomes more
testable - Inner layers independant of UI - Inner layers independant of external parties Separation of Concerns - Bugs more isolated
None
Layer Models - Each layer has own Model classes -
Removes dependancy on external models - Easily map with Mapper classes
ModelA Mapper Model Mapper Model
Enterprise Business Rules - Application Business Objects (Entities) - Unaffected
by operational change - Can create before touching any UI
public class TournamentModel { public String id; public String
name; @SerializedName("full_name") public String status; @SerializedName("date_start") public String dateStart; @SerializedName("date_end") public String dateEnd; public int size; }
Application Business Rules - Application specific business rules - Uses
Cases - Affected by operational change - Isolated from external concerns
public class GetSchedules extends UseCase<ProfileSchedules> { private final SchedulesRepository
schedulesRepository; @Inject public GetSchedules(SchedulesRepository schedulesRepository) { this.schedulesRepository = schedulesRepository; } @Override public Single<ProfileSchedules> buildUseCaseObservable() { return schedulesRepository.getSchedules(); } }
None
Use Case Interface Interface Impl Activity Application Business Rules Interface
Adapters
Interface Adapters - Contains MVP architecture of our app -
Presenters contain ‘callbacks’ - Views define contract for implementation - Mapper converts data from external form
public class UpdatesPresenter extends BasePresenter<UpdatesMvpView> implements SingleObserver<List<Update>> { @Override public
void onSubscribe(Disposable d) { … } @Override public void onSuccess(List<Match> matches) { … } @Override public void onError(Throwable e) { … } }
Presenter Interface Interface Impl Activity Interface Adapters Frameworks & Drivers
Frameworks & Drivers - UI components (Activities, Fragments) - Networking
actions (Retrofit) - Storage (Cache & DB) - Repository Pattern for interacting with these
Repository Interface Repository Impl DataStore Interface DataStore Impl DataStore Impl
DataStore Factory
None
Layer Boundaries - Communication via abstractions (interfaces) - No direct
name references in inner layers - Instead, inner layer provides this interface - aka, The Dependancy Inversion Principle
Not limited to these layers Layer 1 Layer 2 Layer
3 Layer 4
Not limited to these layers Layer 1 Layer 2 Layer
3
Not limited to these layers Layer 1 Layer 2 Layer
3 Layer 4 Layer 5 Layer 6
Test Coverage
None
Learnings
Advantages. - High percentage of code coverage - Incredibly easy
to navigate package structure - Easier to maintain - Allows us to move faster - Focused classes and test classes
- Seperation of concerns - Define, Test, Stabilise before UI
- Futureproof implementations - Clear discipline, good practice - and more…
Disadvantages - Adds initial overhead - Takes time to get
used to - Can feel overkill for some tasks - Difficult to make decisions - Conversion of models between layers
Winston Enterprise Business Rules Application Business Rules Interface Adapters Mobile
UI TV UI Wear UI Frameworks & Drivers
Winston Enterprise Business Rules Application Business Rules Interface Adapters Mobile
UI TV UI Wear UI Frameworks & Drivers @hitherejoe hitherejoe joebirch.co
Resources https://overflow.buffer.com/2016/12/22/rebuild- android-composer/ https://github.com/googlesamples/android- architecture Clean Architecture: A Craftsman's Guide
to Software Structure and Design (Robert C. Martin)