Posts Tagged ‘ComposeMultiplatform’
[KotlinConf2024] KotlinConf2024 Keynote: Powering the Future with Kotlin 2.0
KotlinConf2024, hosted in Copenhagen, welcomed 2,000 attendees and thousands online, kicking off with a vibrant keynote celebrating Kotlin’s evolution. Igor Tolstoy, Kotlin Project Lead at JetBrains, unveiled Kotlin 2.0, powered by the K2 compiler, promising double compilation speeds and robust multiplatform capabilities. Joined by speakers from Meta, Google, Amazon, and JetBrains, the keynote showcased Kotlin’s adoption in 20M lines of code at Meta, Google’s multiplatform push, and Amazon’s AWS SDK. From Compose Multiplatform to AI-driven tools, the event underscored Kotlin’s role in modern development, fueled by a thriving ecosystem.
A Global Stage for Kotlin Innovation
KotlinConf2024 buzzed with energy, uniting 2,000 in-person attendees, online viewers, and 71 global events across 37 countries. The conference featured five parallel sessions, lightning talks, a coach challenge, and code labs by Touchlab. A lively party with a live band and quiz, plus a closing panel, kept spirits high. Attendees donned T-shirts with words like “love,” “code,” and “nothing,” encouraged to form phrases for social media with #KotlinConf. Sponsors, including American Express, powered the event, with their booths bustling in the exhibit hall. The KotlinConf app, built with Compose Multiplatform, guided attendees, urging them to vote on sessions to shape future lineups.
Kotlin 2.0: The K2 Compiler Revolution
Igor Tolstoy introduced Kotlin 2.0, a milestone driven by the K2 compiler. This rewrite delivers a 2x compilation speed boost, slashing wait times for builds. Tested across 10M lines of code from 40 JetBrains and community projects, K2 ensures stability, with 18,000 developers and companies like Meta adopting early versions. The IntelliJ K2 mode, nearing beta, accelerates code highlighting by 1.8x, set to become default in IntelliJ 24.3. Avoiding major syntax changes, K2 fixes longstanding issues, enhancing code consistency and enabling faster language evolution without breaking existing projects.
Meta’s Kotlin Journey: Scaling Android
Eve Maler, an Android engineer from Meta, shared their Kotlin adoption, now spanning 20M lines of code. Since embracing Kotlin-first development three years ago, Meta reduced code by 10%, boosting reliability and developer preference. K2’s incremental compilation cut build times by up to 20%, with 95% of modules now using K2. Tools like IntelliJ’s J2K converter automate Java-to-Kotlin transitions, converting tens of thousands of lines weekly. Meta’s frameworks, including Litho and Dex optimizations, fully support Kotlin, paving the way for a mono-language Android experience, enhancing developer productivity.
Google’s Multiplatform Commitment
Jeffrey van Gogh from Google highlighted their investment in Kotlin, with 33M lines of code internally, doubling since 2023. Kotlin 2.0’s stability thrilled Google, who contributed compiler fixes and ported tools like Android Lint and Compose plugins to K2. The Compose compiler plugin now ships with Kotlin distributions, simplifying updates. Google announced official Android support for Kotlin Multiplatform (KMP) at Google I/O, enabling shared business logic across mobile, web, and desktop. Jetpack libraries like Room and DataStore now support KMP, with Android Studio integrating native KMP tooling, signaling a hybrid model balancing native and shared code.
Compose Multiplatform: Cross-Platform UI
Sebastian Aigner and Ekaterina Petrova celebrated Compose Multiplatform’s stability on Android and desktop, with iOS nearing beta and web in alpha. Used in thousands of apps, including McDonald’s, Compose reduced crashes and unified teams by sharing business logic. New APIs, like Jetpack Navigation and type-safe resources, enhance cross-platform development. iOS-specific improvements, such as VoiceOver integration and refined scroll physics, ensure native experiences. Web support leverages Kotlin/Wasm for high-performance browser apps. Compose’s flexibility lets developers choose how much code to share, from logic to full UI, meeting users across platforms.
Tooling Evolution: Amper and Fleet
JetBrains introduced Amper, a new build tool simplifying multiplatform project setup with minimal configuration. A Kotlin JVM project requires just one line, with dependencies easily added. Amper integrates with IntelliJ and Android Studio, offering quick fixes for project creation. Fleet, a preview multiplatform IDE, unifies Kotlin and Swift development, supporting Xcode projects and cross-language debugging. These tools automate environment checks, provide UI previews, and integrate JetBrains’ AI Assistant for code generation, streamlining workflows and lowering barriers for KMP adoption.
Ecosystem Growth: Libraries and AWS
The Kotlin ecosystem thrives, with a 50% rise in open-source multiplatform solutions. Libraries like Ktor, Serialization, and DateTime gain multiplatform APIs, while new additions like Kandy (data visualization) and DataFrame (data processing) expand capabilities. Amazon’s Julia detailed their AWS SDK for Kotlin, now generally available, built on Smithy for idiomatic APIs. Supporting hundreds of services, including Amazon Bedrock, the SDK leverages coroutines for pagination and streams. Amazon’s internal Kotlin use surged 6x, with teams like Prime Video reporting higher quality and productivity.
AI-Powered Development with JetBrains
Svetlana Isakova closed with JetBrains’ AI Assistant, written in Kotlin and integrated into IntelliJ and Fleet. It offers context-aware code completion, refactoring, and explanations, understanding project structures and dependencies. A Kotlin-specific language model, trained on open-source repositories, powers precise code generation, outperforming larger models in benchmarks. Available in IntelliJ 24.2, it supports multi-line completion and custom contexts. For enterprises, an on-premises version ensures compliance. Open-sourced datasets on Hugging Face further Kotlin’s AI advancements, equipping developers for the AI-driven future.
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[KotlinConf2023] KotlinConf’23 Closing Panel: Community Questions and Future Insights
KotlinConf’23 concluded with its traditional Closing Panel, an open forum where attendees could pose their burning questions to a diverse group of experts from the Kotlin community, including key figures from JetBrains and Google. The panel, moderated by Hadi Hariri, featured prominent names such as Roman Elizarov, Egor Tolstoy, Maxim Shafirov (CEO of JetBrains), Svetlana Isakova, Pamela Hill, Sebastian Aigner (all JetBrains), Grace Kloba, Kevin Galligan, David Blanc, Wenbo, Jeffrey van Gogh (all Google), Jake Wharton (Cash App), and Zac Sweers (Slack), among others.
The session was lively, covering a wide range of topics from language features and tooling to ecosystem development and the future of Kotlin across different platforms.
Kotlin’s Ambitions and Language Evolution
One of the initial questions addressed Kotlin’s overarching goal, humorously framed as whether Kotlin aims to “get rid of other programming languages”. Roman Elizarov quipped they only want to get rid of “bad ones,” while Egor Tolstoy clarified that Kotlin’s focus is primarily on application development (services, desktop, web, mobile) rather than systems programming.
Regarding Kotlin 2.0 and the possibility of removing features, the panel indicated a strong preference for maintaining backward compatibility. However, if a feature were to be considered for removal, it would likely be something with a clearly superior alternative, such as potentially older ways of doing things if newer, more robust mechanisms (like K2 compiler plugins replacing older KAPT mechanisms, hypothetically) became the standard. The discussion also touched on the desire for a unified, official Kotlin style guide and formatter to reduce community fragmentation around tooling, though Zac Sweers noted that even with an official tool, community alternatives would likely persist.
Multiplatform, Compose, and Ecosystem
A significant portion of the Q&A revolved around Kotlin Multiplatform (KMP) and Compose Multiplatform.
* Dart Interoperability: Questions arose about interoperability between Kotlin/Native (especially for Compose on iOS which uses Skia) and Dart/Flutter. While direct, deep interoperability wasn’t presented as a primary focus, the general sentiment was that both ecosystems are strong, and developers choose based on their needs. The panel emphasized that Compose for iOS aims for a native feel and deep integration with iOS platform features.
* Compose UI for iOS and Material Design: A recurring concern was whether Compose UI on iOS would feel “too Material Design” and not native enough for iOS users. Panelists from JetBrains and Google acknowledged this, stressing ongoing efforts to ensure Compose components on iOS adhere to Cupertino (iOS native) design principles and feel natural on the platform. Jake Wharton added that making Kotlin APIs feel idiomatic to iOS developers is crucial for adoption.
* Future of KMP: The panel expressed strong optimism for KMP’s future, highlighting its stability and growing library support. They see KMP becoming the default way to build applications when targeting multiple platforms with Kotlin. The focus is on making KMP robust and ensuring a great developer experience across all supported targets.
Performance, Tooling, and Emerging Areas
- Build Times: Concerns about Kotlin/Native build times, especially for iOS, were acknowledged. The team is continuously working on improving compiler performance and reducing build times, with K2 expected to bring further optimizations.
- Project Loom and Coroutines: Roman Elizarov reiterated points from his earlier talk, stating that Loom is excellent for migrating existing blocking Java code, while Kotlin Coroutines offer finer-grained control and structured concurrency, especially beneficial for UI and complex asynchronous workflows. They are not mutually exclusive and can coexist.
- Kotlin in Gaming: While not a primary focus historically, the panel acknowledged growing interest and some community libraries for game development with Kotlin. The potential for KMP in this area was also noted.
- Documentation: The importance of clear, comprehensive, and up-to-date documentation was a recurring theme, with the panel acknowledging it as an ongoing effort.
- AI and Kotlin: When asked about AI taking developers’ jobs, Zac Sweers offered a pragmatic take: AI won’t take your job, but someone who knows how to use AI effectively might. The panel highlighted that Kotlin is well-suited for building AI tools and applications.
The panel concluded with the exciting reveal of Kotlin’s reimagined mascot, Kodee (spelled K-O-D-E-E), a cute, modern character designed to represent the language and its community. Pins of Kodee were made available to attendees, adding a fun, tangible takeaway to the conference’s close.
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[KotlinConf2023] Compose Multiplatform on iOS: Sharing UIs Across Ecosystems with Sebastian Aigner and Nikita Lipsky
At KotlinConf’23, Sebastian Aigner (Developer Advocate at JetBrains) and Nikita Lipsky (Software Developer for Kotlin at JetBrains) presented an exciting overview of Compose Multiplatform, focusing on its then-Alpha support for iOS. Their session detailed how this JetBrains initiative enables developers to write their user interface once in Kotlin and deploy it across Android, iOS, desktop, and web, fostering significant code sharing and development efficiency. The official documentation for Compose Multiplatform offers further insights.
The presentation began by recapping the classic Kotlin Multiplatform (KMP) use case, which allows sharing of business logic while retaining access to platform-specific APIs. Compose Multiplatform builds upon this by providing a solution for sharing the UI layer itself, addressing scenarios where building and maintaining separate native UIs for each platform is not feasible due to time, resources, or the desire for rapid market entry. While the talk focused on iOS and Android, the speakers emphasized that Compose Multiplatform also supports desktop (stabilized in late 2021) and web targets.
Architecture and Jetpack Compose Foundations
A key point underscored by Sebastian and Nikita was that Compose Multiplatform is built upon Jetpack Compose, Google’s modern declarative UI toolkit for Android, which is 100% Kotlin. This means developers familiar with Jetpack Compose can leverage their existing knowledge and skills to build UIs for iOS and other platforms. The JetBrains team collaborates closely with Google, regularly upstreaming changes to the Jetpack Compose repositories.
Nikita Lipsky delved into the architecture, explaining that official Jetpack Compose itself is already a Kotlin Multiplatform project at its core, with its lowest levels defining Kotlin Multiplatform sources. The composable function concept is an extension to the Kotlin language requiring compiler support, and the entire Compose system is managed by the Compose Runtime. For iOS, Compose Multiplatform renders UI elements by drawing directly onto a CAPI (Canvas API) provided by Skiko, a graphics library that abstracts over Skia (for Android and desktop) and CoreGraphics (for iOS). This allows for consistent rendering across platforms.
Live Demos and iOS Integration
The session featured live demonstrations showcasing the capabilities of Compose Multiplatform on iOS. Sebastian Aigner walked through a sample application, highlighting how standard Jetpack Compose code for UI elements, state management (using remember), layouts (like Column), and modifiers can be shared and run on iOS simulators and devices. He demonstrated features like text input, button interactions, and even integration with iOS-specific functionalities like the share sheet, emphasizing the goal of seamless interoperability.
The speakers also discussed the importance of providing solid accessibility integrations and ensuring smooth performance, even on high-refresh-rate displays, which is an ongoing area of focus for the Kotlin/Native and Compose Multiplatform teams. Interoperability with existing iOS UI code (SwiftUI and UIKit) was also presented as a key feature, allowing for gradual adoption. Developers can embed Compose Multiplatform views within existing SwiftUI applications or, conversely, embed native iOS views within a Compose Multiplatform UI. This flexibility is crucial for teams looking to integrate Compose into their established projects incrementally.
Getting Started and Future Outlook
Sebastian and Nikita provided clear guidance on how developers can start experimenting with Compose Multiplatform for iOS. They pointed to project templates, sample applications available on the Compose Multiplatform GitHub repository (including to-do list apps and code viewers), and updated KMP production samples that now include branches with Compose-based UI implementations. The new memory manager in Kotlin/Native was also mentioned as a significant improvement, simplifying multi-threaded programming for all Kotlin targets, including iOS.
While acknowledging that the iOS target was in Alpha and some areas were still works in progress, the overall message was one of excitement and a call to action for the community. They encouraged developers to explore the technology, provide feedback, and contribute to its evolution. The vision is a future where developers can agree on a delightful way to write UIs for all their target platforms using Kotlin.
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[KotlinConf2023] KotlinConf’23 Keynote: The Future of Kotlin is Bright and Multiplatform
KotlinConf’23 kicked off with an energizing keynote, marking a much-anticipated return to an in-person format in Amsterdam. Hosted by Hadi Hariri of JetBrains, the session brought together key figures from both JetBrains and Google, including Roman Elizarov, Svetlana Isakova, Egor Tolstoy, and Grace Kloba (VP Engineering for Android Developer Experience at Google), to share exciting updates and future directions for the Kotlin language and its ecosystem. The conference also featured a global reach with KotlinConf Global events in 41 countries. The main announcements from the keynote are also available in a blog post on the Kotlin blog.
The keynote celebrated Kotlin’s impressive growth, with statistics highlighting its widespread adoption, particularly in Android development where it’s the most popular language, used in over 95% of the top 1000 Android apps. A major focus was the upcoming Kotlin 2.0, centered around the new K2 compiler, which promises significant performance improvements, stability, and a foundation for future language evolution. The K2 compiler is nearing completion and is set to be released as Kotlin 2.0. The IntelliJ IDEA plugin will also adopt the K2 frontend, aligning with IntelliJ releases.
The Evolution of Kotlin: K2 Compiler and Language Features
The K2 compiler was a central theme of the keynote, marking a major milestone for Kotlin. This new compiler front-end, which also powers the IDE, is designed to be faster, more stable, and enable the development of new language features and tooling capabilities more rapidly. Kotlin 2.0, built on K2, is expected to bring these benefits to all Kotlin developers, enhancing both compiler performance and IDE responsiveness.
Looking beyond Kotlin 2.0, the speakers provided a glimpse into potential future language features that are under consideration. These included:
* Static Extensions: Allowing extension functions to be resolved statically, potentially improving performance and clarity.
* Collection Literals: Introducing a more concise syntax for creating collections, like using square brackets for lists, with efficient implementations.
* Name-Based Destructuring: Offering a more flexible way to destructure objects based on property names rather than just position.
* Context Receivers: A powerful feature for providing contextual information to functions in a more implicit and structured manner. This feature, however, is being approached carefully to ensure it aligns well with Kotlin’s principles.
* Explicit Fields: Providing more control over backing fields for properties.
The team emphasized a careful approach to evolving the language, ensuring new features are well-designed and maintainable. Compiler plugins were also highlighted as an avenue for extending Kotlin’s capabilities.
Kotlin in the Ecosystem: Google’s Investment and Multiplatform Growth
Grace Kloba from Google took the stage to reiterate Google’s strong commitment to Kotlin. She shared insights into Google’s investments in the Kotlin ecosystem, including the development of Kotlin Symbol Processing (KSP) and the continued focus on making Kotlin the default choice for Android development. Google officially supported Kotlin for Android development by early 2017. The Kotlin DSL is now the default for Gradle build scripts in Android Studio, enhancing developer experience with features like semantic highlighting and code completion. Google also actively contributes to the Kotlin Foundation and encourages the community to participate through programs like the Kotlin Foundation Grants Program, which focuses on supporting multiplatform libraries and frameworks.
Kotlin Multiplatform (KMP) was another major highlight, showcasing its growing maturity and adoption. The vision for KMP is to allow developers to share code across various platforms—Android, iOS, desktop, web, and server-side—while retaining the ability to write platform-specific code when needed. The keynote celebrated the increasing number of multiplatform libraries and tools, including KMM Bridge, that simplify KMP development. The future of KMP looks bright, with efforts to further improve the developer experience and expand its capabilities.
Compose Multiplatform and Emerging Technologies
The keynote also showcased the advancements in Compose Multiplatform, JetBrains’ declarative UI framework for building cross-platform user interfaces. A significant announcement was the alpha release of Compose Multiplatform for iOS, enabling developers to write their UI once in Kotlin and deploy it on both Android and iOS, and even desktop and web. This opens up new possibilities for code sharing and faster development cycles for mobile applications.
Finally, the team touched upon Kotlin’s expansion into emerging technologies like WebAssembly (Wasm). JetBrains is developing a new compiler backend for Kotlin targeting WebAssembly with its garbage collection proposal, aiming for high-performance Kotlin code in the browser. Experiments with running Compose applications in the browser using WebAssembly were also mentioned, hinting at a future where Kotlin could offer a unified development experience across an even wider range of platforms. The keynote concluded with an invitation for the community to dive deeper into these topics during the conference and to continue contributing to Kotlin’s vibrant ecosystem.