DevFest 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. Hype Driven Development
   How I learned to stop worrying and love the failures
   DevFest Berlin - Dec 22’ 󰎲
   Ash Davies
   Android / Kotlin GDE - Berlin
   ashdavies@androiddev.social
   

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

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3. Decision-Making
   Hype Driven Development
   ashdavies@androiddev.social
   

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4. Design-Decisions
   Hype Driven Development
   ashdavies@androiddev.social
   

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5. Design Decisions
   Common Tools
   ● 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
   ashdavies@androiddev.social
   

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6. Decision Paralysis
   Hype Driven Development
   ashdavies@androiddev.social
   

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

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8. Decision Fatigue
   Hype Driven Development
   

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

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10. Decision Making
    Hype Driven Development
    ● 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)
    ashdavies@androiddev.social
    

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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
    ashdavies@androiddev.social
    

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

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

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14. Risks of using immature software
    Hype Driven Development
    ● 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
    ashdavies@androiddev.social
    

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15. Risk-Management
    Hype Driven Development
    ashdavies@androiddev.social
    

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16. Risk Management 🤷
    Hype Driven Development
    @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)
    ashdavies@androiddev.social
    

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17. Risk Management 🤷
    Hype Driven Development
    @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
    ashdavies@androiddev.social
    

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

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19. Solutions Looking for a Problem
    Hype Driven Development
    ashdavies@androiddev.social
    

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20. Solutions Looking for a Problem
    Hype Driven Development
    ● 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.
    ashdavies@androiddev.social
    

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21. YAGNI
    You Aren’t Going to Need It
    

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22. The Benefit of @Experimental
    Hype Driven Development
    ● Early adoption of inevitable software (sometimes)
    ● Contribute bug reports or resolutions upstream
    ● New features provide potential market growth
    ● Knowledge sharing in the development community
    ashdavies@androiddev.social
    

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23. Inevitability
    Hype Driven Development
    

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24. Is It Worth It?
    ● Depends on company and team priorities
    ● Development community benefits everybody
    ● Early adopters guide and provide contributions
    ● Development cost absorption
    Hype Driven Development
    ashdavies@androiddev.social
    

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

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26. Open Source to the rescue!
    ● 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
    ashdavies@androiddev.social
    

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27. Use cases for a playground project
    ● 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
    ashdavies@androiddev.social
    

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28. Case Study
    🧪 github.com/ashdavies/playground
    # 451f3d8 | AGP- 7.3.1 | Compose - 1.2.1 | Kotlin 1.7.20
    ashdavies@androiddev.social
    

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

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30. androidstudygroup.github.io/conferences/
    ashdavies@androiddev.social
    

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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"
    }
    }]
    

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

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

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

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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"
    },
    /* ... */
    },
    

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36. ashdavies/playground
    Case Study
    

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37. Case Study
    ashdavies/playground
    

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38. TypeScript
    ashdavies/playground
    

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39. Multiplatform
    ashdavies/playground
    

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40. Kotlin for JavaScript
    kotlinlang.org/docs/js-overview
    kotlin {
    js { nodejs() }
    jvm()
    }
    

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

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42. ✓
    Case Study ashdavies/playground
    

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43. Case Study ashdavies/playground
    

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44. Case Study ashdavies/playground
    

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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
    

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46. Compose
    Multiplatform
    Compose in the
    Cloud ☁
    

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47. Firebase AppCheck
    Compose in the Cloud
    ☁
    github.com/
    ashdavies/playground/
    tree/main/app-check/
    app-check-function
    

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48. Case Study ashdavies/playground
    Py
    

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49. Kotti
    Cat Study
    ashdavies/playground
    

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50. CENSORED
    Py
    Cat Study
    ashdavies/playground
    

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51. Knowledge Sharing
    Hype Driven Development
    ashdavies@androiddev.social
    

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52. Work and Life Balance
    ● 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
    ashdavies@androiddev.social
    

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53. Conclusion
    ● 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
    ashdavies@androiddev.social
    

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

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55. Thanks!
    Ash Davies - Cat Person
    Android / Kotlin GDE - Berlin
    ashdavies@androiddev.social
    

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56. Attributions
    ● “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]
    Hype Driven Development
    

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