Droidcon Berlin: Hype Driven Development

Ever wondered what it would take to combine all the experimental features of a language you love (Spoilers... It's Kotlin!) into one big bundle?

I'm a lover of new and shiny stuff, so let me share with you my experience of using everything shiny, and new, in my pet project, to show you how to *not* do all the things you might want to do with yours!

JetBrains Compose for Desktop, Unstable Coroutines APIs, version catalogues, Gradle composite builds, multiplatform navigation support, multiplatform paging, GraphQl, Firebase Cloud Functions, Molecule, Mosaic, what could go wrong?!

This isn't a fairytale story, when making use of unstable technology, it's not always tested with other unstable technologies; I'm going to tell you of all the things I could have done better, so that you don't need to make the same mistakes!

Transcript

1. Ash Davies
   Senior Android Developer @ Snapp Mobile
   Android & Kotlin GDE Berlin
   Droidcon Berlin - Jul 22’ 󰎲 ☀ 🍻
   Hype Driven Development
   How I learned to stop worrying and love the failures
   @askashdavies
   

   View Slide

2. “Be careful not to do that thing I
   knowingly did despite my own advice”
   - Every one of my talks, ever.
   

   View Slide

3. Hype Driven Development
   Decision-Making
   @askashdavies
   

   View Slide

4. Hype Driven Development
   Design-Decisions
   @askashdavies
   

   View Slide

5. ● Language: Kotlin, Java, Scala, or Swift
   ● Dependencies: Dagger, DI, or Koin
   ● Threading: Coroutines, RxJava, or Java
   ● Serialization: Gson, Moshi, Jackson, or KotlinX
   ● Network: Retrofit, OkHttp, or Ktor
   ● Image Loading: Coil, Glide, or Picasso
   Design Decisions
   Common Tools
   

   View Slide

6. Decision Paralysis
   Hype Driven Development
   

   View Slide

7. Advantages:
   ● Low engineering complexity.
   ● Staffing needs are minimal
   ● Timeline is manageable
   Disadvantages:
   ● Doesn’t solve the problem
   Design Decisions
   Option 1: Do Nothing
   

   View Slide

8. Decision Fatigue
   Hype Driven Development
   

   View Slide

9. How I learned to stop worrying and love the failures
   Hype Driven Development
   @askashdavies
   

   View Slide

10. ● Stakeholder influence, feature driven requirements
    ● Reaction to issues in the codebase (ie. tech debt)
    ● New tech, promises faster, easier solutions
    ● Not limited to engineering (CEO Driven Development)
    Hype Driven Development
    Decision Making
    

    View Slide

11. Law of the Instrument
    “Birmingham Screwdriver”
    “I suppose it is tempting, if the only tool
    you have is a hammer, to treat everything as
    if it were a nail.”
    - Abraham Maslow
    

    View Slide

12. ● Enticement to use a product or service, usually monetised for enterprise
    ● Seemingly benevolent, promises developer interests
    ● Trustworthy whilst goals are aligned
    Hype Driven Development
    Community Influence
    

    View Slide

13. ● Heavy social media utilisation (Twitter, Reddit, etc)
    ● Human psychology (Argumentum ad novitatem)
    ● Promise to make life easier, better, faster, stronger…
    Hype Driven Development
    Community Influence
    

    View Slide

14. ● Dependent on third party development commitment
    ● Libraries sometimes need years to evolve and mature
    ● Very difficult to revert if results are undesired
    ● More likely to produce poor quality code
    ● Often new learning curve introduced
    ● Investment of unknown future
    Hype Driven Development
    Risks of using immature software
    

    View Slide

15. Hype Driven Development
    Risk-Management
    @askashdavies
    

    View Slide

16. @Deprecated(
    message = "CoroutineScope.rxCompletable is deprecated in favour of top-level rxCompletable",
    level = DeprecationLevel.ERROR,
    replaceWith = ReplaceWith("rxCompletable(context, block)")
    )
    public fun CoroutineScope.rxCompletable(
    context: CoroutineContext = EmptyCoroutineContext,
    block: suspend CoroutineScope.() -> Unit
    ): Completable = rxCompletableInternal(this, context, block)
    Hype Driven Development 󰤇
    Risk Management
    

    View Slide

17. @RequiresOptIn(message = "This API is experimental. It may be changed in the future without notice.")
    @Retention(AnnotationRetention.BINARY)
    @Target(AnnotationTarget.CLASS, AnnotationTarget.FUNCTION)
    annotation class MyDateTime // Opt-in requirement annotation
    @MyDateTime
    class DateProvider // A class requiring opt-in
    Hype Driven Development 󰤇
    Risk Management
    

    View Slide

18. ● Annotations, experimental, deprecated, Opt-In
    ● Coding for disposability
    ● Isolated API surface
    ● Coding workshops
    ● Feasibility investigations (timeboxed)
    Hype Driven Development
    Risk management
    

    View Slide

19. Hype Driven Development
    Solutions looking for a problem
    

    View Slide

20. ● New technology might not be appropriate for your project
    ● Be cautious of finding problems that don’t exist
    ● If it ain’t broke, don’t fix it.
    Hype Driven Development
    Solutions looking for a problem
    

    View Slide

21. YAGNI
    You Aren’t Going to Need It
    

    View Slide

22. ● Early adoption of inevitable software (sometimes)
    ● Contribute bug reports or resolutions upstream
    ● New features provide potential market growth
    ● Knowledge sharing in the development community
    Hype Driven Development
    What is the benefit of experimental
    

    View Slide

23. Inevitability
    Hype Driven Development
    

    View Slide

24. ● Depends on company and team priorities
    ● Development community benefits everybody
    ● Early adopters guide and provide contributions
    ● Development cost absorption
    Hype Driven Development
    Is it worth it?
    

    View Slide

25. ● Not a good idea to follow hype in a production codebase
    ● Still eager to try out new technologies
    Hype Driven Development
    How to get away with it anyway…
    

    View Slide

26. ● Many engineers maintain a playground repository
    ● Many examples of new tech in Google repos
    ● Many open source projects needing maintainers
    ● Contribute to a project that can make use of it
    Hype Driven Development
    Open Source to the rescue!
    

    View Slide

27. ● Majority of mobile applications are a user friendly facade for API data
    ● There are many open APIs available providing niche data sets
    Hype Driven Development
    Use cases for playground project…
    

    View Slide

28. Case Study
    🧪 github.com/ashdavies/playground
    # ae2d602 | AGP- 7.0.4 | Compose - 1.2.0-alpha01-dev667 | Kotlin 1.6.10
    @askashdavies
    

    View Slide

29. ● Takes conference data from open source ASG contributions
    ● Built heavily around Compose for Desktop
    ● Backed by Cloud Functions and Firebase Firestore
    ● Shared models across platforms
    ● Quasi-monorepo for side projects
    Hype Driven Development
    Case Study ashdavies/playground
    

    View Slide

30. androidstudygroup.github.io/conferences/
    @askashdavies
    

    View Slide

31. [{
    "name": "droidcon-berlin-2021.md",
    "path": "_conferences/droidcon-berlin-2021.md",
    "sha": "9361834b3e310ffd8992c1020eb868ebb56c564a",
    "size": 239,
    "url": "https://api.github.com/repos/AndroidStudyGroup/conferences/contents/_conferences/droidcon-berlin-2021.md?ref=gh-pages",
    "html_url": "https://github.com/AndroidStudyGroup/conferences/blob/gh-pages/_conferences/droidcon-berlin-2021.md",
    "git_url": "https://api.github.com/repos/AndroidStudyGroup/conferences/git/blobs/9361834b3e310ffd8992c1020eb868ebb56c564a",
    "download_url": "https://raw.githubusercontent.com/AndroidStudyGroup/conferences/gh-pages/_conferences/droidcon-berlin-2021.md",
    "type": "file",
    "_links": {
    "self": "https://api.github.com/repos/AndroidStudyGroup/conferences/contents/_conferences/droidcon-berlin-2021.md?ref=gh-pages",
    "git": "https://api.github.com/repos/AndroidStudyGroup/conferences/git/blobs/9361834b3e310ffd8992c1020eb868ebb56c564a",
    "html": "https://github.com/AndroidStudyGroup/conferences/blob/gh-pages/_conferences/droidcon-berlin-2021.md"
    }
    }]
    

    View Slide

32. ---
    name: "Droidcon"
    website: https://www.berlin.droidcon.com/
    location: Berlin, Germany
    date_start: 2022-07-06
    date_end: 2022-07-08
    ---
    

    View Slide

33. GraphQL
    docs.github.com/en/graphql
    

    View Slide

34. query conferences {
    repository(owner: "AndroidStudyGroup", name: "conferences") {
    events: object(expression: "HEAD:_conferences") {
    ... on Tree {
    entries {
    data: object {
    ... on Blob {
    oid
    text
    }
    # ...
    }
    

    View Slide

35. "data": {
    "repository": {
    "events": {
    "entries": [
    {
    "data": {
    "oid": "9a2a79fe414cf02fd0904c02ef7ce416344d747d",
    "text": "---\nname: \"360|AnDev\"\nwebsite: http://360andev.com/\nlocation: Denver, Colorado, USA\n\n
    date_start: 2016-07-28\ndate_end: 2016-07-29\n\ncfp:\nstart: 2016-01-27\nend: 2016-04-29\nsite: http://360andev.com
    /call-for-papers/\n---\n"
    },
    /* ... */
    },
    

    View Slide

36. Case Study
    ashdavies/playground
    

    View Slide

37. Case Study
    ashdavies/playground
    

    View Slide

38. TypeScript
    ashdavies/playground
    

    View Slide

39. Multiplatform
    ashdavies/playground
    

    View Slide

40. Kotlin for JavaScript
    kotlinlang.org/docs/js-overview
    kotlin {
    js { nodejs() }
    jvm()
    }
    val dyn: dynamic = ...
    // 'whatever' is not defined anywhere
    dyn.whatever(1, "foo", dyn)
    dyn.whatever(*arrayOf(1, 2, 3))
    dyn.foo().bar.baz()
    

    View Slide

41. Case Study ashdavies/playground
    

    View Slide

42. Case Study ashdavies/playground
    

    View Slide

43. Case Study
    ashdavies/playground
    Kotti
    

    View Slide

44. Case Study
    ashdavies/playground
    CENSORED
    Py
    

    View Slide

45. Kotlin all the things
    An experiment in creating a mobile app and
    firebase cloud functions in Kotlin
    – Andrew Reitz
    andrewreitz.com/tech_blog/kotlin-multiplatform-android-firebase
    

    View Slide

46. Case Study ashdavies/playground
    ✓
    

    View Slide

47. Case Study ashdavies/playground
    Py
    

    View Slide

48. Coming Soon…
    ashdavies/playground
    Compose
    Multiplatform
    

    View Slide

49. ● Using Firebase AppCheck API for multiplatform REST API access
    ● Combine dependencies in composite build plugins and version catalogues
    ● Mosaic library for Compose Desktop [Success]
    Hype Driven Development
    One of many failures…
    

    View Slide

50. ● Not everybody can, wants, or should spend time outside of work on pet projects
    ● Some are fortunate to have time for research, and community involvement
    ● Advocate for time to evaluate feasible technology, timeboxed, hack-week, etc
    ● Propose solutions for internal tooling, don’t forget the business case 🤑!
    ● Develop for disposability when in production (see “Everything is an API”)
    Hype Driven Development
    Work and life balance
    

    View Slide

51. ● HDD is high risk for production environments
    ● Satisfy dev thirst in a safe environment
    ● Use learnings to advise feasibility
    ● Share learnings with the community
    Hype Driven Development
    Conclusion
    

    View Slide

52. “Every existing thing is born without
    reason, prolongs itself out of weakness
    and dies by chance.”
    - Jean-Paul Sartre
    

    View Slide

53. Ash Davies
    Android & Kotlin GDE Berlin
    @askashdavies
    Thanks!
    @askashdavies
    Kotti
    Follow for more cat pics!
    

    View Slide

54. Hype Driven Development
    Links
    ● “Feature” [monkeyuser.com]
    ● Hype Driven Development [blog.daftcode.pl/hype-driven-development-3469fc2e9b22]
    ● Instant Gratification Monkey [waitbutwhy.com]
    ● Kotlin All the Things [andrewreitz.com/tech_blog/kotlin-multiplatform-android-firebase]
    ● Untitled [goose.game]
    

    View Slide