Tools of the Trade #DCNYC18

With all the great resources and libraries available, building a new mobile app is easier than it’s ever been! But when your users come to expect your product to be as reliable as running water at a global scale, you’ll need to go above and beyond what’s currently available.

Join Ty as he walks down memory lane to cover the history of the Uber app development process. He’ll cover how it grew, the pain points discovered and lessons learned, and the tooling developed and open-sourced to scale to millions of users served by hundreds of contributors across many apps.

Topics covered will include: Buck, Uber’s architecture solution, RIBs, Proper Experimentation, Continuous integration, Code Verification and Static Analysis, and the company processes needed to facilitate a large app.

Transcript

1. Tools
   of the Trade
   Ty Smith
   @tsmith
   

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2. @tsmith
   

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3. @tsmith
   

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4. @tsmith
   

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5. @tsmith
   

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6. @tsmith
   

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7. @tsmith
   

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8. @tsmith
   

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9. @tsmith
   

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10. @tsmith
    

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11. @tsmith
    

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12. @tsmith
    

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13. @tsmith
    

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14. @tsmith
    

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15. @tsmith
    

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16. @tsmith
    

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17. Topics
    — Monorepo
    — Architecture
    — Libraries and Tools
    @tsmith
    

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18. MONO
    REPO
    @tsmith
    

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19. Pain Points
    — Dependency Hell
    — Architectural Silos
    — Long Build times
    @tsmith
    

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20. ABI Breaking change
    @tsmith
    

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21. Many Repos
    Depedency hell
    ~/Uber/rider-android/build.gradle
    dependencies {
    implementation "com.uber:partner-funnel:1.2.3"
    implementation "com.uber:single-sign-on:0.7.0"
    implementation "com.uber:storage:2.1.0"
    implementation "com.uber:networking:2.3.1"
    implementation "com.uber:analytics:1.9.0"
    }
    ~/Uber/partner-funnel-android/build.gradle
    dependencies {
    implementation "com.uber:storage:2.2.0"
    implementation "com.uber:networking:2.0.0"
    implementation "com.uber:analytics:1.3.5"
    }
    @tsmith
    

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22. Monorepo
    ~/Uber/Android
    |-- .git
    |-- build.gradle
    |-- apps
    | |-- rider
    | |-- driver
    | |-- eats
    |-- features
    | |-- partner-funnel
    | |-- single-sign-on
    |-- libraries
    | |-- storage
    | |-- networking
    | |-- analytics
    @tsmith
    

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23. Monorepo
    ~/Uber/android/apps/rider/build.gradle
    dependencies {
    implementation project(":features:partner-funnel")
    implementation project(":features:single-sign-on")
    implementation project(":libraries:storage")
    implementation project(":libraries:networking")
    implementation project(":libraries:analytics")
    }
    ~/Uber/android/features/partner-funnel/build.gradle
    dependencies {
    implementation project(":libraries:storage")
    implementation project(":libraries:networking")
    implementation project(":libraries:analytics")
    }
    @tsmith
    

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24. Buck
    @tsmith | buckbuild.com
    

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25. Buck
    — Output based
    — Highly Parellelizable
    — Fast!
    !
    — IDE Integration
    @tsmith
    

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26. Buck
    @tsmith
    

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27. OKBuck
    A gradle plugin that lets developers utilize the Buck
    build system on a gradle project.
    @tsmith | github.com/uber/okbuck
    

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28. OKBuck
    plugins {
    id 'com.uber.okbuck' version '0.36.0'
    }
    @tsmith | github.com/uber/okbuck
    

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29. OKBuck
    ./gradlew :buckWrapper
    //List targets
    ./buckw list
    //Build Target
    ./buckw build
    @tsmith | github.com/uber/okbuck
    

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30. Exopackage
    @tsmith | buckbuild.com/article/exopackage.html
    

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31. @tsmith
    

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32. Submit Queue
    @tsmith
    

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33. Architecture
    @tsmith | Photo by Rich Niewiroski Jr. | CC BY 2.5
    

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34. @tsmith
    

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35. 99.99%
    reliability of core flows
    Enable global rollback of core flows to a guaranteed
    working state
    @tsmith
    

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36. Support growth for
    years
    Narrow and decouple functionality as much as possible
    @tsmith
    

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37. Rails
    for Design and Code
    Guidelines for both architecture and design
    @tsmith
    

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38. Monitoring
    is a First-Class Citizen
    Automatic analytics, logging, debugging, and tracing
    @tsmith
    

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39. De-risk
    Experimentation
    Application framework with plugin API
    @tsmith
    

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40. Make
    Magic
    Performance second to none, graceful degradation on
    low-end devices and networks
    @tsmith
    

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41. MVC MVVM VIPER
    Fat View
    Controller
    Fat View
    Controller
    View based logic
    separation
    Locked view &
    business tree
    Locked view &
    business tree
    Locked view &
    business tree
    @tsmith
    

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42. @tsmith | github.com/uber/ribs
    

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43. RIBs
    @tsmith | github.com/uber/ribs
    

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44. RIBs
    @tsmith | github.com/uber/ribs
    

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45. RIBs
    @tsmith | github.com/uber/ribs
    

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46. RIBs
    @tsmith | github.com/uber/ribs
    

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47. RIBs
    @tsmith | github.com/uber/ribs
    

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48. RIBs
    @tsmith | github.com/uber/ribs
    

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49. RIBs
    Communication
    @tsmith | github.com/uber/ribs
    

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50. Libraries
    @tsmith | Photo by DAVID ILIFF | CC BY-SA 3.0
    

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51. RIBs
    Intellij Plugin
    @tsmith | github.com/uber/RIBs/tree/master/android/tooling/rib-intellij-plugin
    

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52. Motif
    A simple DI API for Android / Java
    @tsmith | github.com/uber/motif
    

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53. Motif
    @motif.Scope
    interface MainScope {
    ChildScope child();
    @motif.Objects
    class Objects {
    @Expose
    Database database() {
    return new Database();
    }
    }
    }
    @tsmith | github.com/uber/motif
    

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54. Motif
    @motif.Scope
    interface ChildScope {
    ChildController controller();
    @motif.Objects
    class Objects {
    ChildView view() {
    return new ChildView();
    }
    ChildController controller(Database database, ChildView view) {
    return new ChildController(database, view);
    }
    }
    }
    @tsmith | github.com/uber/motif
    

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55. @tsmith
    

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56. Crumb
    An annotation processor for breadcrumbing metadata
    across compilation boundaries
    @tsmith | github.com/uber/crumb
    

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57. Crumb
    @tsmith | github.com/uber/crumb
    

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58. RIBs
    Plugins
    class FooPluginFactory :
    PluginFactory {
    override fun pluginSwitch() = FOO_PLUGIN_SWITCH
    override fun isApplicable(intent : Intent) = intent.hasExtra("bar")
    override fun createNewPlugin(intent : Intent) = FooPlugin(intent)
    }
    @tsmith | github.com/uber/crumb
    

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59. RIBs
    Plugins
    class BarPluginPoint : PluginPoint() {
    override val internalPluginFactories = listOf(FooPluginFactory())
    }
    @tsmith | github.com/uber/crumb
    

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60. RIBs
    Plugins
    val barPluginPoint = BarPluginPoint(abFramework)
    val BarPlugin : BarPlugin? = pluginPoint.getPlugin(intent)
    barPlugin?.doWork()
    @tsmith | github.com/uber/crumb
    

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61. @tsmith
    

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62. Autodispose
    Automatic binding+disposal of RxJava 2 streams.
    @tsmith | github.com/uber/autodispose
    

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63. Autodispose
    observable
    .doStuff()
    .as(autoDisposable(this))
    .subscribe { ... }
    @tsmith | github.com/uber/autodispose
    

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64. Autodispose
    — Maybe
    — LifecycleScopeProvider
    — ScopeProvider
    @tsmith | github.com/uber/autodispose
    

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65. Autodispose
    Extras!
    — Kotlin extensions
    — RX lifecycle extensions
    — Architecture Components adapter
    — Plugins
    — Errorprone checker
    @tsmith | github.com/uber/autodispose
    

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66. @tsmith
    

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67. Workflow
    Represent a workflow of reactive steps
    @tsmith | github.com/uber/RIBs/tree/master/android/libraries/rib-workflow
    

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68. Workflow
    — Step
    — ActionableItem
    — Workflow
    @tsmith
    

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69. Workflow
    @tsmith | github.com/uber/RIBs/tree/master/android/libraries/rib-workflow
    

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70. Workflow
    class SingleSignOnWorkflow :
    HelixRootWorkflow() {
    override fun getSteps(rootActionableItem : AppRootActionableItem,
    deeplink : SingleSignOnDeepLink ) :
    Step {
    return rootActionableItem
    .onStep(waitUntilSignedIn())
    .onStep(GoToMain())
    .onStep(showFullScreenRib(singleSignOnRib(deeplink)))
    }
    }
    @tsmith | github.com/uber/RIBs/tree/master/android/libraries/rib-workflow
    

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71. Workflow
    override fun waitUntilSignedIn() :
    Step {
    return Step.from(
    mutableSession
    .getAuthStateAsync()
    .filter { it is AuthState.AuthStateLoggedIn }
    .take(1)
    .map { Step.Data.toActionableItem(this) }
    .singleOrError())
    }
    @tsmith | github.com/uber/RIBs/tree/master/android/libraries/rib-workflow
    

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72. @tsmith
    

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73. @tsmith
    

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74. @tsmith
    

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75. Artist
    An artist creates views. Artist is a Gradle plugin that
    codegens a base set of Android Views.
    @tsmith | github.com/uber/artist
    

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76. Artist
    — Stencil: The View Generator
    — Trait: Reusable functionality
    @tsmith | github.com/uber/artist
    

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77. Artist
    class VisibilityTrait : Trait {
    override fun generateFor( type: Builder,
    initMethod: MethodSpec.Builder,
    rClass: ClassName,
    baseType: String) {
    listOf("visible", "invisible", "gone")
    .forEach { type.addMethod(createVisibilityConvenienceMethod(it)) }
    }
    private fun createVisibilityConvenienceMethod(type: String): MethodSpec {
    return MethodSpec.methodBuilder("is${type.capitalize()}")
    .addModifiers(Modifier.PUBLIC)
    .returns(TypeName.BOOLEAN)
    .addStatement("return getVisibility() == \$T.${type.toUpperCase()}", TypeNames.Android.View)
    .build()
    }
    }
    @tsmith | github.com/uber/artist
    

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78. Artist
    class SwitchStencil : ViewStencil(
    extendedType = "android.support.v7.widget.SwitchCompat",
    constructorCount = 3,
    defaultAttrRes = "switchStyle",
    addedTraits = VisibilityTrait::class.java) {
    override fun name() = "FooSwitch"
    }
    @tsmith | github.com/uber/artist
    

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79. Artist
    public class FooSwitch extends SwitchCompat {
    // Constructors
    // protected init method - provided in every stencil
    public boolean isVisible() {
    return getVisibility() == View.VISIBLE;
    }
    public boolean isGone() {
    return getVisibility() == View.GONE;
    }
    public boolean isInvisible() {
    return getVisibility() == View.INVISIBLE;
    }
    }
    @tsmith | github.com/uber/artist
    

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80. Stylist
    A stylist creates cool styles. Stylist is a Gradle plugin
    that codegens a base set of Android XML themes.
    @tsmith | github.com/uber/stylist
    

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81. Stylist
    @AutoService(ThemeStencilProvider::class)
    class SampleThemeStencilProvider : ThemeStencilProvider {
    private val textSizes = StyleItemGroup(
    StyleItem("textSizeSmall", "12dp"),
    StyleItem("textSizeMedium","16dp"),
    StyleItem("textSizeLarge", "20dp")
    )
    override fun stencils() = linkedSetOf(
    ThemeStencil("Theme.Sample.Dark", "Theme.AppCompat"),
    ThemeStencil("Theme.Sample.Light", "Theme.AppCompat.Light")
    )
    override fun globalStyleItemGroups() = linkedSetOf(
    textSizes
    )
    }
    @tsmith | github.com/uber/stylist
    

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82. Stylist
    
    
    <br/><item name="textSizeSmall">12dp</item><br/><item name="textSizeMedium">16dp</item><br/><item name="textSizeLarge">20dp</item><br/>
    <br/><item name="textSizeSmall">12dp</item><br/><item name="textSizeMedium">16dp</item><br/><item name="textSizeLarge">20dp</item><br/>
    
    @tsmith | github.com/uber/stylist
    

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83. @tsmith
    

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84. Lint
    class SwitchCompatUsageXmlDetector : ResourceXmlDetector() {
    override val applicableElements = listOf("android.support.v7.widget.SwitchCompat")
    override fun visitElement(context:XmlContext, element : Element) : override {
    context.report(
    Issue.create("SwitchCompatUsage",
    "Don't use base view SwitchCompat",
    "Use Provided FooSwitch",
    Category.CORRECTNESS, 6, Severity.ERROR,
    Implementation(XmlUViewUsageDetector::class.java, Scope.RESOURCE_FILE_SCOPE)),
    element, context.getLocation(element), LINT_ERROR_MESSAGE)
    }
    }
    @tsmith
    

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85. Herald
    @tsmith | www.phacility.com/phabricator/herald
    

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86. "I call it my billion-dollar mistake.
    It was the invention of the
    null reference"
    - Sir Charles Antony Richard Hoare
    @tsmith | github.com/uber/NullAway
    

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87. Errorprone
    public class MyActivity extends Activity {
    @Override
    public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    AndroidInjection.inject(this);
    }
    }
    @tsmith | errorprone.info
    

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88. Nullaway
    A tool to help eliminate NullPointerExceptions in your
    Java code
    @tsmith | github.com/uber/NullAway
    

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89. Nullaway
    static void log(Object x) {
    System.out.println(x.toString());
    }
    static void foo() {
    log(null);
    }
    @tsmith | github.com/uber/NullAway
    

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90. Nullaway
    warning: [NullAway] passing @Nullable parameter 'null' where @NonNull is required
    log(null);
    ^
    @tsmith | github.com/uber/NullAway
    

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91. Nullaway
    static void log(@Nullable Object x) {
    if (x != null) {
    System.out.println(x.toString());
    }
    }
    @tsmith | github.com/uber/NullAway
    

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92. RAVE
    Runtime Annotation Validation Engine
    Ensure models adhere to the set of expectations that
    are described by their annotations
    @tsmith | github.com/uber/RAVE
    

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93. RAVE
    public final class SampleFactory implements ValidatorFactory {
    @NonNull
    @Override
    public BaseValidator generateValidator() {
    return new SampleFactory_Generated_Validator();
    }
    }
    @tsmith | github.com/uber/RAVE
    

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94. RAVE
    @Validated(factory = SampleFactory.class)
    public class SimpleMatchModel {
    private String match;
    private static final String MATCHED = "Matched";
    private static final String NOT_MATCHED = "NotMatched";
    @StringDef({MATCHED, NOT_MATCHED})
    @Retention(RetentionPolicy.SOURCE)
    @interface StringVals { }
    @NonNull
    @StringVals
    public String getMatch() {
    return match;
    }
    }
    @tsmith | github.com/uber/RAVE
    

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95. RAVE
    public void validateMyModel(SimpleModel myModel) {
    try {
    Rave.getInstance().validate(myModel);
    } catch (RaveException e) {
    // handle rave validation error.
    }
    }
    @tsmith
    

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96. @tsmith
    

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97. Thri!y
    https://github.com/Microsoft/thrifty
    Wire
    https://github.com/square/wire
    @tsmith
    

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98. @tsmith
    

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99. Uber Open Source
    github.com/uber/artist
    github.com/uber/autodispose
    github.com/uber/crumb
    github.com/uber/motif
    github.com/uber/nullaway
    github.com/uber/okbuck
    github.com/uber/rave
    github.com/uber/ribs
    github.com/uber/stylist
    @tsmith
    

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100. Resources
     Architecture rewrite - t.uber.com/ribs-1
     Dependency hierarchies - t.uber.com/ribs-2
     RIBs - t.uber.com/ribs-3
     Plugins - t.uber.com/ribs-4
     Monorepo - t.uber.com/monorepo-1
     @tsmith
     

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101. Tools
     of the Trade
     Ty Smith
     @tsmith
     

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