Effective mobile engineering to make product successful

Have you ever wondered how the best product ideas succeed? It's not only great timing, product-market fit or marketing activities. It's also about business and engineering cooperation.

In this presentation, I'll talk about our experiences with making great (and bad) ideas happen. How to deliver fast, learn from mistakes and keep your users happy (and crash free!).

I will show how the team of a few engineers can build the app used globally. How we develop and maintain our code, test, deliver, learn and iterate.

Transcript

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2. fail fast
   

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3. Anyone who has never made a mistake
   has never tried anything new.
   -Albert Einstein
   

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4. IT BIZ
   ↔
   Me
   

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5. Fail fast,
   Fail often,
   Fail better,
   Succeed
   

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6. Ship fast,
   Iterate often,
   Don’t crash,
   Succeed
   Fail fast,
   Fail often,
   Fail better
   

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7. #
   KPIs
   

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8. Crash-free users >99.5%
   Release once a week
   

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9. New app once a week???
   
   

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10. Release
    Once a month
    x1 x2 x5 x6
    x3 x4 x7 x8
    team’s capacity
    

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11. x1 x2 x3 x4
    x5 x6 x7 x8 build 1 checking
    Dev QA/Business
    build1
    build2
    Week 1
    Week 2
    Week 3
    “W
    hat’s wrong,
    W
    hat’s ok?”
    “W
    hat’s wrong,
    W
    hat’s ok?”
    build 2 checking
    

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12. x1 x2 x3 x4
    x5 x6 x7 x8 build 1 testing
    x1’ x2’ x4’ build 2 testing
    Dev QA/Business
    build1
    build2
    Week 1
    Week 2
    Week 3
    “we don’t like
    x5, x8”
    “we don’t like
    x1, x2, x4”
    x5’ x8’
    Week 4
    

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13. x1 x2 x3 x4
    x5 x6 x7 x8 build 1 testing
    x1’ x2’ x4’ build 2 testing
    Dev QA/Business
    build1
    build2
    build3
    Week 1
    Week 2
    Week 3
    fixes
    x5’ x8’ x1’ x2’ x4'
    Week 4
    more fixes
    “checking them now..”
    x5’ x8’
    RELEASE!!!
    

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14. x1 x2 y2 z1
    x3 y1 z2 z3
    team’s capacity (same as previous)
    Release
    Once a week
    

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15. Week 1 x1 x2 x1’ x2’ x1 x2 x1’
    Dev QA/Business
    

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16. x1’ x2’ x1’
    build 1
    build 2
    Week 1 x1 x2 x1 x2
    Dev QA/Business
    

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17. x1’
    feedback 1
    feedback 2
    Week 1 x1 x2 x1’ x2’ x1 x2
    Dev QA/Business
    

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18. Week 1 x1 x2 x1’ x2’
    Week 2 x3
    x1 x2 x1’
    Dev QA/Business
    x2’ x3
    build 4
    build 5
    release candidate v1
    RELEASE!
    

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19. Week 1 x1 x2 x1’ x2’
    Week 2 x3 y1 y2
    x1 x2 x1’
    Dev QA/Business
    x2’ y1
    x3
    feedback 1
    build
    Week 3
    

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20. Week 1 x1 x2 x1’ x2’
    Week 2 x3 y1 y2
    x1 x2 x1’
    Dev QA/Business
    y1’ z1 z2
    Week 3
    x2’ y1
    y1’ z1
    y2
    x3
    v2
    RELEASE!
    

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21. Week 1 x1 x2 x1’ x2’
    Week 2 x3 y1 y2
    x1 x2 x1’
    Dev QA/Business
    y1’ z1 z2
    Week 3
    x2’ y1
    y1’ z1
    y2
    x3
    z3
    v3
    RELEASE!
    Week 4 z1’ z2’ z3 z1’ z2’
    z2
    

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22. x1 x2 y2 z1
    x3 y1 z2 z3
    x1 x2 x5 x6
    x3 x4 x7 x8
    vs
    

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23. x1 x2 y2 z1
    x3 y1 z2 z3
    x1 x2 x5 x6
    x3 x4 x7 x8
    • Same context, reasonable overhead
    • Different context, a lot to keep in mind
    How many things to have in mind by
    engineers
    Software 

    engineer
    focus
    QA 

    engineer
    focus
    QA and software

    engineer
    focus
    

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24. How many things can go wrong
    x1 x2 y2 z1
    x3 y1 z2 z3
    x1 x2 x5 x6
    x3 x4 x7 x8
    • Same context, reasonable overhead
    • less things can break
    • Different context, a lot to keep in mind
    • more things can break
    

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25. Business starts learning from
    here
    x1 x2 y2 z1
    x3 y1 z2 z3
    x1 x2 x5 x6
    x3 x4 x7 x8
    • Same context, reasonable overhead
    • less things can break
    • business can iterate fast
    • Different context, a lot to keep in mind
    • more things can break
    • business can’t iterate fast
    “We’ve learned that
    you don’t have to build this”
    “We’ve learned that
    you didn’t have to build this”
    

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26. 
    SHIP FAST
    

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27. ?
    x2
    x3
    x1
    

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28. Coding
    Testing
    and
    review
    x2
    x3
    x1
    Release
    candidate
    

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29. ⌚
    ???
    Coding
    Testing
    and
    review
    x2
    x3
    x1
    Release
    candidate
    

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30. Manual
    tests
    Others
    What’s
    new
    Build
    apk
    Internal
    distrib
    Internal build
    Coding
    Testing
    and
    review
    x2
    x3
    x1
    Release
    candidate
    

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31. Sign

    apk
    Release

    notes
    Internal

    distrib
    Update
    assets
    Store

    upload
    RC distribution
    Coding
    Testing
    and
    review
    x2
    x3
    x1
    Release
    candidate
    

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32. +2h
    x number of loops
    +2h
    Coding
    Testing
    and
    review
    x2
    x3
    x1
    Release
    candidate
    Internal build RC distrib
    x
    Rollout
    +1-2 days
    

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33. +2h
    Coding
    Testing
    and
    review
    x2
    x3
    x1
    Release
    candidate
    Internal build RC distrib
    x
    Rollout
    +1-2 days
    +2h
    x number of loops
    

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34. clean the
    project
    unit tests
    tests
    coverage
    lint
    checks
    assemble
    apk
    distribute notify
    INTERNAL BUILD
    Coding
    Testing
    and
    review
    

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35. INTERNAL BUILD
    $ ./gradlew
    clean
    testDebugUnitTest
    testDebugUnitTestCoverage
    lintStaging
    assembleStaging
    crashlyticsUploadDistributionStaging
    clean the
    project
    unit tests
    tests
    coverage
    lint
    checks
    assemble
    apk
    distribute notify
    pipeline {
    agent { node { label 'mobile' }}
    //...
    stages {
    stage("Build and distribute debug") {
    steps {
    }
    }
    }
    }
    

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36. New
    feature
    branch
    On
    demand
    Create
    release
    branch
    Build and
    distribute
    RC
    Create
    Merge Request
    Notify
    reviewer
    New 

    release candidate
    Create
    merge
    request
    Bump
    version
    code
    4 clicks
    10 clicks
    3 lines of
    code
    Push to
    master
    Push to
    Play Store
    beta
    Production
    app quick
    tests
    Store release
    Build,
    check,
    distribute
    apk
    30min of
    clicking
    Trigger
    Actions
    Savings
    

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37. Run all
    tests
    Create
    report
    Send
    report to
    slack
    Nightly
    tests
    Setup and
    run
    simulators
    Every
    24hrs
    

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38. Every
    24hrs
    Update 

    /res/values
    Remove
    unused
    resources
    create
    merge
    request
    Update
    translations
    Fetch
    translation
    sfrom API
    lint checks
    

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39. apply plugin: 'io.fabric'
    apply plugin: 'jacoco'
    apply plugin: 'com.getkeepsafe.dexcount'
    apply plugin: 'com.github.triplet.play'
    def process_language(language):
    print('Starting processing of: ' + language)
    is_default_language = language == ApiConfig.DEFAULT_LANGUAGE
    translations = translations_api.get_translations()
    if '--android' in sys.argv:
    parsed_keys = transform_all_translations(translations)
    android_exporter = ATranslationsExporter(parsed_keys, lang_code)
    android_exporter.generate_translations()
    if is_default_language:
    android_exporter.cleanup_android_new_translations()
    pipeline {
    triggers {
    gitlab(triggerOnPush: true, branchFilterType: 'All')
    }
    stage("Build debug") {
    when { branch 'dev' }
    steps { sh './gradlew clean assembleDebug --stacktrace' }
    }
    }
    

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40. Coding
    Testing
    and
    review
    x2
    x3
    x1
    Release
    candidate
    Internal build RC distrib
    auto
    x
    Rollout
    auto
    +1-2 days
    

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41. *
    QUALITY
    ASSURANCE
    

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42. 
    Key feature can be tested manually
    only once.
    

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43. RC QA
    fast feedback QA
    Development
    3 STAGES OF QA
    Unit tests
    Lint checks
    Manual tests
    Functional
    tests
    End-to-end
    tests
    Test infra
    maintenance
    

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44. LINT CHECKS
    

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45. UNIT
    TESTING
    

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46. Written by devs -
    Test single units
    100% of tests must pass ✅
    

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47. @Test

    public void testInit_whenConditionsMet_thenShouldShowRatingBox() {

    when(rateBoxManager.shouldAskForRate()).thenReturn(true);

    activityPresenter.initView();
    verify(activityMock, once()).showRateBox();
    }
    >200sec to
    find this
    screen/popup
    <1sec to
    execute test
    

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48. @Test

    public void testCriteria_whenAllMet_thenShouldShowRateBox() {

    when(appDataMock.getAppInstallTime()).thenReturn(DATE_7_DAYS_AGO);

    when(rateBoxReminderMock.isDelayed()).thenReturn(false);
    assertEquals(rateBoxManager.shouldAskForAppRate(), true);

    }
    @Test

    public void testCriteria_whenAppFreshlyInstalled_thenShouldntShowRateBox() {
    when(appDataMock.getAppInstallTime()).thenReturn(DATE_TODAY);

    when(rateBoxReminderMock.isDelayed()).thenReturn(true);

    assertEquals(rateBoxManager.shouldAskForAppRate(), false);

    }
    CRITERIA UNIT TESTS
    

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49. 
    COVERAGE 100% (?)
    

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50. @Test

    public void testSetGet() {

    assertFalse(model.isSet());
    model.setItTo(true);

    assertTrue(model.isSet());
    model.setItTo(false);
    assertFalse(model.isSet());

    }
    COVERAGE 100%
    @Test

    public void testConstructor() {

    model = new Model(true);

    assertTrue(model.isSet());

    }
    

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51. 2 unit tests,
    0 integration tests
    

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52. COVERAGE 50-60%
    & FAST FORWARD TO QA
    COVERAGE 100%
    

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53. INTEGRATION
    TESTING
    

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54. Built by QA engineers
    Run on emulator
    Hermetic env
    

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55. Data and settings
    Use cases,
    presentation logic
    

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56. mocks, init config System under test
    Data and settings
    Use cases,
    presentation logic
    

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57. mocks System under test
    Use cases,
    presentation logic
    

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58. mocks
    Screen by
    screen flow:
    - Splash
    - Login
    - Main Screen
    - List if items
    API calls
    +
    database
    operations
    Screen by
    screen flow:
    - Splash
    - Login
    - Main Screen
    - List if items
    API calls
    +
    database
    operations
    5s
    5s 5s
    0s
    

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59. Android instrumentation test template
    AVD
    manager
    System under
    testing
    

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60. Android instrumentation test template
    Fake data
    (e.g. json file)
    AVD
    manager
    System under
    testing
    Mock objects
    

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61. Android instrumentation test template
    Init state
    Activity
    System under
    testing
    Fake data
    (e.g. json file)
    AVD
    manager
    Mock objects
    

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62. @RunWith(AndroidJUnit4.class)
    public class ForceAppUpdate_MockTests extends AzimoTestContainer {
    @Rule public DaggerMockRule daggerRule = DaggerMockUtils.defaultDaggerMockRule();
    @Mock ApiVersionChecker apiVersionChecker;
    public void setupLogic() {
    when(apiVersionChecker.shouldUpdateApplication()).thenReturn(true);
    }
    @Test
    public void testForceAppUpdate_ifAppIsTooOld_shouldShowUpdateAzimoScreen() throws Exception {
    /* Data mocking (App-State unrelated) */
    when(apiVersionChecker.shouldUpdateApplication()).thenReturn(true);
    /* Config init */
    TestLauncher.init()
    .setting_setInputToUser(TestUsers.getTestUserNoTransfersNoRecipients())
    .setting_useStartingPoint(LauncherStartingCondition.USER)
    .run();
    /* Test Start */
    appTooOldNavi().waitForEnteredActivity(AppTooOldActivity.class);
    appTooOldAsserts().assertThat_correctTitleIsDisplayed();
    appTooOldAsserts().assertThat_correctDescriptionIsDisplayed();
    appTooOldAsserts().assertThat_correctButtonDescriptionIsDisplayed();
    }
    }
    

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63. @RunWith(AndroidJUnit4.class)
    public class ForceAppUpdate_MockTests extends AzimoTestContainer {
    @Rule public DaggerMockRule daggerRule = DaggerMockUtils.defaultDaggerMockRule();
    @Mock ApiVersionChecker apiVersionChecker;
    public void setupLogic() {
    when(apiVersionChecker.shouldUpdateApplication()).thenReturn(true);
    }
    @Test
    public void testForceAppUpdate_ifAppIsTooOld_shouldShowUpdateAzimoScreen() throws Exception {
    /* Data mocking (App-State unrelated) */
    when(apiVersionChecker.shouldUpdateApplication()).thenReturn(true);
    /* Config init */
    TestLauncher.init()
    .setting_setInputToUser(TestUsers.getTestUserNoTransfersNoRecipients())
    .setting_useStartingPoint(LauncherStartingCondition.USER)
    .run();
    /* Test Start */
    appTooOldNavi().waitForEnteredActivity(AppTooOldActivity.class);
    appTooOldAsserts().assertThat_correctTitleIsDisplayed();
    appTooOldAsserts().assertThat_correctDescriptionIsDisplayed();
    appTooOldAsserts().assertThat_correctButtonDescriptionIsDisplayed();
    }
    }
    Mocking
    Init state
    activity
    test
    

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64. END-TO-END
    TESTING
    

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65. Simulate end user 5
    End-to-end features
    Up to 2 hours ⏲
    

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67. How to get there ?
    

    Be 1% better every release
    

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68. early 2015 - no unit tests (product launch)
    late 2015 - 20% coverage, manual testing
    2016 - 40% coverage, started QA engineering
    2017 - 60% coverage, core features e2e
    2018 - 50-60% coverage, all features e2e
    someday - “Lint zero” project
    

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69. Automation Test Supervisor
    Automated test emulator run plugin
    Check on
    github.com/AzimoLabs
    

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70. Testing
    Fast
    feedback
    QA
    Release
    candidate
    Internal build RC distrib
    auto
    min x
    Rollout
    auto
    asap
    RC
    testing
    x2
    x3
    x1
    Development
    Coding
    Code
    checks
    ✔
    ✔ ✔
    

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71. Testing
    Fast
    feedback
    QA
    Release
    candidate
    Internal build RC distrib
    auto
    min x
    Rollout
    auto
    asap
    RC
    testing
    x2
    x3
    x1
    Development
    Coding Code
    checks
    ✔
    ✔ ✔
    

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72. Write code that matters 8
    Separate logic from SDK /
    Code must be testable
    

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73. 
    IF WRITING TESTS IS HARD, THAT
    MIGHT BE A BUG
    

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74. Activity
    Data Navigation
    Networking
    UI View logic
    ALL-IN-ONE
    Testing?
    External QA, only end-to-end.
    

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75. Model
    Presenter
    View
    Database
    Navigation API
    View logic
    TESTABLE
    Data logic
    Unit testing - moderate (a lot to mock, incl. SDK)
    Integration testing - moderate
    End-to-end testing - easy
    Stores
    

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76. View
    Stores
    Navigator
    API
    View logic Use cases
    Repositories,
    Managers
    5-STARS
    Database
    

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77. UNIT TESTING
    View
    Stores
    Navigator
    API
    View logic Use cases
    Repositories,
    Managers
    Database
    

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78. View
    Stores
    Navigator
    API
    View logic Use cases
    Repositories,
    Managers
    Database
    UNIT TESTING
    

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79. View
    Stores
    Navigator
    API
    View logic Use cases Repositories,
    Managers
    Database
    UNIT TESTING
    

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80. System under test Mocks
    INTEGRATION TESTING
    View
    Stores
    Navigator
    API
    View logic Use cases Repositories,
    Managers
    Database
    

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81. System under test
    View
    Stores
    Navigator
    API
    View logic Use cases
    Repositories,
    Managers
    Database
    END-TO-END TESTING
    

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82. EASY TO “THREAD”
    Always UI
    Ensure
    background
    thread
    Always
    background
    View
    Stores
    Navigator
    API
    View logic Use cases
    Repositories,
    Managers
    Database
    

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83. SDK VS LOGIC
    Android
    SDK
    Plain code
    View
    Stores
    Navigator
    API
    View logic Use cases
    Repositories,
    Managers
    Database
    

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84. THE BEST
    ARCHITECTURE
    The one that makes the developers
    team the most productive.
    

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85. ARCHITECTURE PATTERNS
    • MVP, MVVM
    • App Architecture
    Components
    • Others (see Android
    Blueprints)
    github.com/googlesamples/

    android-architecture
    

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86. WRITE LOGIC
    THAT MATTERS!
    GENERATE EVERYTHING ELSE. 8
    

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87. @BindView(R.id.tvTitle)
    TextView tvTitle;
    @BindColor(R.color.brand)
    int colorBrand;
    @BindString(R.string.hello)
    String strHello;
    @Override
    protected void onCreate(Bundle state) {
    // LOGIC THAT MATTERS TO YOU
    }
    WITH BUTTERKNIFE
    

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88. private TextView tvTitle;
    private String title;
    private int colorBrand;
    @Override
    protected void onCreate(Bundle state) {
    // A LITTLE BIT OF INIT
    tvTitle = findViewById(R.string.project_id);
    colorBrand = ContextCompat.getColor(this, R.color.brand);
    strHello = getString(R.string.strHello);
    // A LITTLE BIT OF LOGIC
    }
    WITHOUT BUTTERKNIFE
    

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89. @Inject
    ActivityPresenter presenter;
    @Inject
    AnimationUtils animationUtils;
    @Inject
    ListAdapter listAdapter;
    @Override
    protected void onCreate(Bundle state) {
    // LOGIC THAT MATTERS TO YOU
    }
    WITH DAGGER
    

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90. ActivityPresenter presenter;
    AnimationUtils animationUtils;
    ListAdapter listAdapter;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    // A LITTLE BIT OF INIT
    presenter = new ActivityPresenter(this, /* x other dependencies */);
    animationUtils = new AnimationUtils(this);
    listAdapter = new listAdapter(this, /* y other dependencies*/);
    // A LITTLE BIT OF LOGIC

    // …
    }
    WITHOUT DAGGER
    

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91. MORE DAGGER
    (INJECT EVERYTHING)
    @ActivityScope
    public class SupportAdapter extends SimplestRecyclerViewAdapter {
    public static final int ITEM_VIEW_TYPE_CATEGORY = 0;
    //…and 11 other types
    //Factories for all items types
    private final Map vhFactories;
    @Inject
    public SupportAdapter(Map vhFactories) {
    this.vhFactories = vhFactories;
    }
    @Override
    public SupportViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
    //Take factory for given view type and create ViewHolder
    return vhFactories.get(viewType).createViewHolder(parent);
    }
    }
    

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92. @Module
    abstract class BindingsModule {
    @Binds @IntoMap
    @IntKey(ITEM_VIEW_TYPE_LOADING)
    abstract SupportViewHolderFactory bindLoadingViewHolderFactory(LoadingViewHolderFactory factory);
    @Binds @IntoMap
    @IntKey(ITEM_VIEW_TYPE_ARTICLE)
    abstract SupportViewHolderFactory bindArticleViewHolderFactory(ArticleViewHolderFactory factory);
    @Binds @IntoMap
    @IntKey(ITEM_VIEW_TYPE_CTA_CHAT)
    abstract SupportViewHolderFactory bindCtaChatViewHolderFactory(CtaChatViewHolderFactory factory);
    // and all other factories…
    }
    

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93. @AutoFactory(implementing = SupportViewHolderFactory.class)
    public class ArticleViewHolder extends SupportViewHolder {
    @BindView(R2.id.text) TextView text;
    @BindView(R2.id.divider) View divider;
    ArticleViewModel viewModel;
    private final ArticleListener host;
    public ArticleViewHolder(@Provided LayoutInflater inflater,
    @Provided ArticleListener host,
    ViewGroup parent) {
    super(inflater, parent, R.layout.as_item_support_article);
    this.host = host;
    }
    @Override
    public void bind(SupportViewModel item) {
    viewModel = (ArticleViewModel) item;
    text.setText(viewModel.title);
    ViewUtils.visibility(divider, !viewModel.last);
    }
    @OnClick(R2.id.contentContainer)
    void itemClicked() {
    host.articleSelected(viewModel);
    }
    }
    Logic that matters!
    Code generated for us
    

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94. DAGGER2RECIPES
    github.com/frogermcs
    • Async injection
    • MultiBinding + Autofactory
    • Demo app with all-in-one
    • Multimodule demo app
    

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95. void handleApiErrorResponse(HttpException e) {
    GeneralErrorResponse errorResponse = errorResponseParser.valueOf(e.response());
    switch (errorResponse.genericErrorCode) {
    case ErrorCodes.CODE_401_DEVICE_NOT_AUTHENTICATED:
    ((BaseActivity) activityCompanion).logoutUser();
    break;
    case ErrorCodes.CODE_403_AUTHENTICATE_ACCOUNT_BLOCKED:
    ((BaseActivity) activityCompanion).showAccountBlockedError();
    break;
    case ErrorCodes.CODE_422_USER_EMAIL_ALREADY_TAKEN:
    if (activityCompanion instanceof CreateAccountActivity) {
    ((CreateAccountActivity) activityCompanion).showEmailAlreadyRegistered();
    }
    break;
    case ErrorCodes.CODE_404_USER_INVALID_INVIATION:
    if (activityCompanion instanceof CreateAccountActivity) {
    ((CreateAccountActivity) activityCompanion).showInvalidInvitation();
    }
    break;
    default:
    handleGeneralError(errorResponse, e);
    break;
    }
    }
    

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96. ERROR HANDLER
    @AutoHandler
    public interface SimplerErrorListener {
    @ErrorCode(CODE_403_AUTHENTICATE_ACCOUNT_BLOCKED)
    void accountBlocked();
    @ErrorCode(CODE_422_USER_EMAIL_ALREADY_TAKEN)
    void emailTaken();
    @ErrorCode(codes = {"501", "503"})
    void serverError();
    }
    Check on
    github.com/AzimoLabs
    /Api-Error-Handler
    

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97. MODULARIZE ⚛
    

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98. Objects graph
    CODE MODULES
    ApiModule
    DataModule UtilsModule
    UserManager
    CountriesRepo
    CurrenciesRepo
    …
    OKHttpClient
    ApiRestClient
    AuthInterceptor
    LoggingInterceptor
    CurrencyFormatter
    ExchangeCalculator
    …
    more…
    

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99. Objects graph (AppComponent)
    ApiModule
    DataModule UtilsModule more…
    @Singleton
    @Component(
    modules = {
    AppModule.class,
    DataModule.class,
    ApiModule.class,
    UtilsModule.class,
    }
    )
    public interface AppComponent {
    }
    

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100. Objects graph (AppComponent)
     ApiModule
     DataModule UtilsModule more…
     @Module
     public class ApiModule {
     @Provides
     @Singleton
     public OkHttpClient provideOkHttpClient() {/**/}
     @Provides
     @Singleton
     public Retrofit provideRestAdapter(OkHttpClient okHttpClient) {/**/}
     @Provides
     @Singleton
     public GithubApiService provideGithubApiService(Retrofit restAdapter) {
     return restAdapter.create(GithubApiService.class);
     }
     }
     

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101. Objects graph (AppComponent)
     ApiModule
     DataModule UtilsModule more…
     Our DataModule
     >600 lines of code
     

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102. Objects graph (AppComponent)
     FEATURE MODULES
     CountriesModule
     PaymentModule CardsModule
     PaymentManager
     PaymentConfigRepo
     PaymentApiService
     CountriesManager
     CountriesRepository
     CountriesConfig
     CountriesApi
     CardsManager
     CardsRepository
     CardsEncryption
     CardsTokeniseApi
     more…
     

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103. CountriesModule
     PaymentModule CardsModule
     DataModule
     vs
     >
     ?
     @
     ?
     > @
     

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104. @Singleton
     @Component(
     modules = {
     AzimoAppModule.class,
     DataModule.class,
     ApiModule.class,
     AppConfigModule.class,
     UtilsModule.class,
     BackendModule.class,
     GcmModule.class,
     ApiAuthorisationModule.class,
     ViewMappersModule.class,
     AnalyticsModule.class,
     MatchingModule.class,
     CardsModule.class,
     FormattersModule.class,
     TransactionDownloadModule.class,
     PeopleDownloadModule.class,
     AppsTrackingModule.class,
     DocUploaderModule.class,
     PricingModule.class,
     ZendeskModule.class,
     PayinModule.class,
     CheckoutModule.class,
     SharedEverywhereModule.class,
     PaymentModule.class,
     RateModule.class,
     EstimatedDeliveryModule.class,
     ZendeskModule.class,
     UserFactsModule.class,
     UserFactsDownloadModule.class,
     FirebaseCardsApiModule.class
     }
     )
     public interface AppComponent {
     }
     

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105. View Slide

106. MODULARIZE MORE
     ⚛
     ⚛ ⚛
     

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107. MULTI-FEATURE APP
     SupportFeature
     App
     ChatModule
     FAQModule
     Support logic
     PaymentFeature
     CardsModule
     Payments logic
     PaymentModule
     Base
     Shared features
     …
     CountriesFeature CurrenciesFeature UserFactsFeature …
     …
     

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108. SupportFeature
     App
     ChatModule
     FAQModule
     Support logic
     PaymentFeature
     CardsModule
     Payments logic
     PaymentModule
     Base
     Shared features
     …
     CountriesFeature CurrenciesFeature UserFactsFeature …
     …
     • Quick compilation
     • Quick unit tests
     • Clean structure
     MULTI-FEATURE APP
     

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109. SupportFeature
     App
     ChatModule
     FAQModule
     Support logic
     PaymentFeature
     CardsModule
     Payments logic
     PaymentModule
     Base
     Shared features
     …
     CountriesFeature CurrenciesFeature UserFactsFeature …
     …
     • Configuration 

     complexity
     • Low solutions 

     maturity
     • High entry level
     MULTI-FEATURE APP
     

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110. THE REALITY
     SupportFeature
     App
     Base
     Shared features
     Still App…
     Countries
     Feature
     UserFacts
     Feature
     …
     PaymentFeature
     …
     Transactions

     Feature
     Still App…
     

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111. PROJECT MODULARIZATION
     Multi
     module
     setup
     

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112. PROJECT MODULARIZATION
     Multi
     module
     setup
     Dagger 2
     across
     modules
     

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113. PROJECT MODULARIZATION
     Multi
     module
     setup
     Dagger 2
     across
     modules
     Unit testing
     

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114. PROJECT MODULARIZATION
     Multi
     module
     setup
     Dagger 2
     across
     modules
     Unit testing
     Tests 

     coverage
     

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115. PROJECT MODULARIZATION
     Multi
     module
     setup
     Dagger 2
     across
     modules
     Unit testing
     Tests 

     coverage
     github.com/frogermcs/MultiModuleGithubClient
     End-to-end
     testing
     Proguard
     configuration
     more in the
     future…
     Done during:
     

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116. ?A
     PEOPLE
     

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117. Crash-free users >99.5%
     Release once a week
     

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118. !!!
     Crash-free users >99.5%
     Release once a week
     

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119. ✋
     STOP THE LINE
     

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120. Every employee on the assembly line
     has a responsibility to push a big red button
     that stops everything whenever they notice
     a defect
     

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121. Release every week + stop the line
     40 releases in last 12 months.
     

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122. Release weeks in last 12 months
     

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123. Release once a week - achieved in 83%
     Crash free >99.5% - achieved in 100%
     

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124. THEY TELL
     We don’t have time do it right
     YOU ASK
     Do you have time to do it twice?
     

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125. @froger_mcs
     mirek@azimo.com
     medium.com/@froger_mcs
     Link to this presentation
     will be there
     More about how we
     build the technology
     Ask me anything
     you want :)
     

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