Posts Tagged ‘Programming’
[KotlinConf2025] Closing Panel
The concluding panel of KotlinConf2025 offered a vibrant and candid discussion, serving as the capstone to the conference. The diverse group of experts from JetBrains, Netflix, and Google engaged in a wide-ranging dialogue, reflecting on the state of Kotlin, its evolution, and the path forward. They provided a unique blend of perspectives, from language design and backend development to mobile application architecture and developer experience. The conversation was an unfiltered look into the challenges and opportunities facing the Kotlin community, touching on everything from compiler performance to the future of multiplatform development.
The Language and its Future
A central theme of the discussion was the ongoing development of the Kotlin language itself. The panel members, including Simon from the K2 compiler team and Michael from language design, shared insights into the rigorous process of evolving Kotlin. They addressed questions about new language features and the careful balance between adding functionality and maintaining simplicity. A notable point of contention and discussion was the topic of coroutines and the broader asynchronous programming landscape. The experts debated the best practices for managing concurrency and how Kotlin’s native features are designed to simplify these complex tasks. There was a consensus that while new features are exciting, the primary focus remains on stability, performance, and enhancing the developer experience.
The State of Multiplatform Development
The conversation naturally shifted to Kotlin Multiplatform (KMP), which has become a cornerstone of the Kotlin ecosystem. The panelists explored the challenges and successes of building applications that run seamlessly across different platforms. Representatives from companies like Netflix and AWS, who are using KMP for large-scale projects, shared their experiences. They discussed the complexities of managing shared codebases, ensuring consistent performance, and maintaining a robust build system. The experts emphasized that while KMP offers immense benefits in terms of code reuse, it also requires a thoughtful approach to architecture and toolchain management. The panel concluded that KMP is a powerful tool, but its success depends on careful planning and a deep understanding of the underlying platforms.
Community and Ecosystem
Beyond the technical discussions, the panel also reflected on the health and vibrancy of the Kotlin community. A developer advocate, SA, and others spoke about the importance of fostering an inclusive environment and the role of the community in shaping the language. They highlighted the value of feedback from developers and the critical role it plays in guiding the direction of the language and its tooling. The discussion also touched upon the broader ecosystem, including the various libraries and frameworks that have emerged to support Kotlin development. The panel’s enthusiasm for the community was palpable, and they expressed optimism about Kotlin’s continued growth and adoption in the years to come.
Links:
[KotlinConf2025] The Life and Death of a Kotlin Native Object
The journey of an object within a computer’s memory is a topic that is often obscured from the everyday developer. In a highly insightful session, Troels Lund, a leader on the Kotlin/Native team at Google, delves into the intricacies of what transpires behind the scenes when an object is instantiated and subsequently discarded within the Kotlin/Native runtime. This detailed examination provides a compelling look at a subject that is usually managed automatically, demonstrating the sophisticated mechanisms at play to ensure efficient memory management and robust application performance.
The Inner Workings of the Runtime
Lund begins by exploring the foundational elements of the Kotlin/Native runtime, highlighting its role in bridging the gap between high-level Kotlin code and the native environment. The runtime is responsible for a variety of critical tasks, including memory layout, garbage collection, and managing object lifecycles. One of the central tenets of this system is its ability to handle memory allocation and deallocation with minimal developer intervention. The talk illustrates how an object’s structure is precisely defined in memory, a crucial step for both performance and predictability. This low-level perspective offered a new appreciation for the seamless operation that developers have come to expect.
A Deep Dive into Garbage Collection
The talk then progresses to the sophisticated mechanisms of garbage collection. A deep dive into the Kotlin/Native memory model reveals a system designed for both performance and concurrency. Lund describes the dual approach of a parallel mark and concurrent sweep and a concurrent mark and sweep. The parallel mark and concurrent sweep is designed to maximize throughput by parallelizing the marking phase, while the concurrent mark and sweep aims to minimize pause times by allowing the sweeping phase to happen alongside application execution. The session details how these processes identify and reclaim memory from objects that are no longer in use, preventing memory leaks and maintaining system stability. The discussion also touches upon weak references and their role in memory management. Lund explains how these references are cleared out in a timely manner, ensuring that objects that should be garbage-collected are not resurrected.
Final Thoughts on the Runtime
In his concluding remarks, Lund offers a final summary of the Kotlin/Native runtime. He reiterates that this is a snapshot of what is happening now, and that the details are subject to change over time as new features are added and existing ones are optimized. He emphasizes that the goal of the team is to ensure that the developer experience is as smooth and effortless as possible, with the intricate details of memory management handled transparently by the runtime. The session serves as a powerful reminder of the complex engineering that underpins the simplicity and elegance of the Kotlin language, particularly in its native context.
Links:
[KotlinConf2024] Revamping Kotlin’s Type System: A Vision
At KotlinConf2024, Ross Tate, a programming language researcher, exposed critical flaws in Kotlin’s type system, including undecidability and unsoundness, which can crash compilers or misclassify types. Collaborating with the Kotlin team, he proposed pragmatic restrictions to ensure reliability and introduced extensions like categorized union types for error handling. Ross shared a long-term strategy to make type checking sound, decidable, and extensible, inviting developers to shape Kotlin’s future through feedback, balancing theory with practical needs.
Uncovering Type System Flaws
Kotlin’s type system, while powerful, is flawed. Ross revealed its undecidability, where subtyping questions can encode Turing machines, causing unpredictable compiler behavior. This stems from Java’s similar issues, as proven by Ru Gregori’s research. Unsoundness is equally concerning—Ross demonstrated a program tricking the compiler into treating an Int as a String using type projections and nulls. These flaws, also present in Java and Scala, undermine reliability, making robust type checking a priority for Kotlin’s evolution.
The Dangers of Unsound Programs
Unsoundness risks memory corruption. Ross presented a fast integer-to-string converter that, without proper checks, could introduce vulnerabilities. Initially, Kotlin’s compiler rejected it, as Int isn’t a subtype of String. However, adding a magic configuration with existential type projections bypassed this safeguard, fooling the compiler. Adapted from Java and Scala examples, this highlights a shared problem. Ross stressed that revamping Kotlin involves eliminating such unintentional backdoors, ensuring only explicit casts compromise safety, preserving developer trust.
Type Inference Challenges
Type inference, vital for Kotlin’s usability, struggles with decomposition. Ross showed a tree class for sorting adjectives, which type-checks when whole but fails when split into smaller parts. The compiler couldn’t infer the branch type B, violating the principle that breaking programs into smaller units shouldn’t break type checking. Co-variance adjustments revealed a principal type (Nothing), but Java’s undecidable subtyping influenced Kotlin’s conservative design. Ross aims to fix this, ensuring inference supports modular, predictable codebases.
Pragmatic Restrictions for Decidability
To address undecidability, Ross proposed separating interfaces into “shapes” (type constraints, like Comparable) and “materials” (data types, like function interfaces). Analyzing 135 million lines of Java code, he found all interfaces fit one category, making subtyping decidable in practice. By embedding this pattern into Kotlin, type checking becomes reliable and efficient, running in polynomial time. This separation also improves usability, as hovering over a variable avoids irrelevant types like Comparable<*>, aligning with developer expectations.
Categorized Union Types for Errors
Ross previewed categorized union types, restricted to prevent exponential type-checking costs. Types are grouped into categories (e.g., Null, Any, Error), allowing unions only across categories, like T | NoSuchValue. This enables distinguishing custom errors from null, as shown in a lastOrError function. Operators like !. (propagate error), !: (replace error), and !! (throw exception) mirror nullable syntax, simplifying libraries. Q&A clarified errors remain manipulable values, enhancing flexibility without compromising efficiency.
Enhancing Error Handling
The proposed error system differentiates errors (values) from exceptions (control flow). Error classes include a throw method for conversion to exceptions, while Throwable subclasses form distinct categories, enabling multi-catch via union types. A try-catch variant infers the union of thrown types, supporting exhaustive checks with Java’s typed exceptions. This design, inspired by Rust’s result pattern, balances explicit error handling with backward compatibility, addressing interoperability concerns raised in Q&A about Java’s ecosystem.
Shaping Kotlin’s Future
Ross emphasized that these changes are experimental, requiring prototypes, trials, and community input. Challenges like name resolution and method overloading need strategies, and features must cohere. He invited feedback via issue KT-68296, especially on error naming (e.g., “Error” vs. “Sentinel”) to avoid Java confusion. The talk underscored Kotlin’s shift toward optimizing its own experience, even at the cost of some Java interop precision, ensuring a reliable, extensible type system for future developers.
Links:
[DevoxxFR2025] Go Without Frills: When the Standard Library Suffices
Go, the programming language designed by Google, has gained significant popularity for its simplicity, efficiency, and strong support for concurrent programming. A core philosophy of Go is its minimalist design and emphasis on a robust standard library, encouraging developers to “do a lot with a little.” Nathan Castelein, in his presentation, championed this philosophy, demonstrating how a significant portion of modern applications can be built effectively using only Go’s standard library, without resorting to numerous third-party dependencies. He explored various native packages and compared their functionalities to well-known third-party alternatives, showcasing why and how returning to the fundamentals can lead to simpler, more maintainable, and often equally performant Go applications.
The Go Standard Library: A Powerful Foundation
Nathan highlighted the richness and capability of Go’s standard library. Unlike some languages where the standard library is minimal, Go provides a comprehensive set of packages covering a wide range of functionalities, from networking and HTTP to encoding/decoding, cryptography, and testing. He emphasized that these standard packages are well-designed, thoroughly tested, and actively maintained, making them a reliable choice for building production-ready applications. Focusing on the standard library reduces the number of external dependencies, which simplifies project management, minimizes potential security vulnerabilities introduced by third-party code, and avoids the complexities of managing version conflicts. It also encourages developers to gain a deeper understanding of the language’s built-in capabilities.
Comparing Standard Packages to Third-Party Libraries
The core of Nathan’s talk involved comparing functionalities provided by standard Go packages with those offered by popular third-party libraries. He showcased examples in areas such as:
– Web Development: Demonstrating how to build web servers and handle HTTP requests using the net/http package, contrasting it with frameworks like Gin, Echo, or Fiber. He would have shown that for many common web tasks, the standard library provides sufficient features.
– Logging: Illustrating the capabilities of the log/slog package (introduced in Go 1.21) for structured logging, comparing it to libraries like Logrus or Zerolog. He would have highlighted how log/slog provides modern logging features natively.
– Testing: Exploring the testing package for writing unit and integration tests, perhaps mentioning how it can be used effectively without resorting to assertion libraries like Testify for many common assertion scenarios.
The comparison aimed to show that while third-party libraries often provide convenience or specialized features, the standard library has evolved to incorporate many commonly needed functionalities, often in a simpler and more idiomatic Go way.
The Benefits of a Minimalist Approach
Nathan articulated the benefits of embracing a “Go without frills” approach. Using the standard library more extensively leads to:
– Reduced Complexity: Fewer dependencies mean a simpler project structure and fewer moving parts to understand and manage.
– Improved Maintainability: Code relying on standard libraries is often easier to maintain over time, as the dependencies are stable and well-documented.
– Enhanced Performance: Standard library implementations are often highly optimized and integrated with the Go runtime.
– Faster Compilation: Fewer dependencies can lead to quicker build times.
– Smaller Binaries: Avoiding large third-party libraries can result in smaller executable files.
He acknowledged that there are still valid use cases for third-party libraries, especially for highly specialized tasks or when a library provides significant productivity gains. However, the key takeaway was to evaluate the necessity of adding a dependency and to leverage the powerful standard library whenever it suffices. The talk encouraged developers to revisit the fundamentals and appreciate the elegance and capability of Go’s built-in tools for building robust and efficient applications.
Links:
- Nathan Castelein: https://www.linkedin.com/in/nathan-castelein/
- Shodo Lille: https://shodo.io/
- Devoxx France LinkedIn: https://www.linkedin.com/company/devoxx-france/
- Devoxx France Bluesky: https://bsky.app/profile/devoxx.fr
- Devoxx France Website: https://www.devoxx.fr/
[KotlinConf2024] The Best Programmer I Know: Insights from KotlinConf2024
At KotlinConf2024, Daniel Terhorst-North shared a heartfelt reflection on the traits of exceptional programmers, drawing from his 30-year career and a colleague who embodies these qualities. Without a formal degree, this programmer excels by starting tasks, prioritizing outcomes, simplifying solutions, choosing tools wisely, and fostering team growth. Daniel’s narrative, blending personal anecdotes and practical advice, inspires developers to cultivate curiosity, resilience, and empathy while building impactful software.
Starting with Action
Great programmers dive into tasks without hesitation. Daniel recounted how his colleague tackles projects by starting anywhere, embracing the unknown. This “just start” mindset counters procrastination, which Daniel admits to masking as research. By iterating rapidly—trying, failing, and learning—programmers overcome perfectionism and ego. Daniel likened progress to navigating a grid city, moving stoplight to stoplight, accepting delays as part of the journey, ensuring steady advancement toward solutions.
Prioritizing Outcomes Over Code
Building products, not just code, defines effective programming. Daniel emphasized that emotional investment should focus on outcomes, not code, which is merely a means. The best programmers write minimal, high-quality code, holding no attachment to it. Studying the domain reveals user needs, as Daniel learned during a financial project where ignorance of CDOs led to unintended consequences. Observing users’ frustrations, like manual data entry, uncovers opportunities to eliminate friction, enhancing product value.
Simplifying the Complex
Exceptional programmers see through complexity to find simple solutions. Daniel shared a story of his colleague bypassing bloated Java web servers by writing a lean one from the HTTP spec. In another case, a team debating JSON libraries was guided to implement a simple interface for nine serialized objects, avoiding heavy dependencies. Writing clear documentation, like a streamlined README, drives “embarrassment-driven refactoring,” ensuring solutions remain concise and maintainable, solving only what’s necessary.
Choosing Tools for the Problem
Tool selection should prioritize the product, not team familiarity. Daniel recounted a team learning Scala to sketch code quickly, despite no prior experience, proving adaptability trumps comfort. He advocated for polyglot programming, using Advent of Code to learn Rust and Go, which broadened his problem-solving perspective. By minimizing cognitive distance between problem and solution, as Rich Hickey’s “Simple Made Easy” suggests, programmers select tools that evolve with project needs, ensuring flexibility.
Fostering Team Care
Great programmers uplift their teams. Daniel finds joy in pairing and teaching, inspired by an XKCD comic about the “lucky 10,000” who learn something new daily. He creates environments for learning, drawing from jiu-jitsu’s teaching-first philosophy. Sending teams home to rest, as Daniel advocates, boosts effectiveness, while assuming positive intent—per Virginia Satir’s family therapy principle—builds empathy, transforming conflicts into opportunities for collaboration and growth.
Building Psychological Safety
Psychological safety, per Amy Edmondson’s research, is vital for high-performing teams. Daniel explained that safe teams encourage saying “I don’t know,” seeking help, and disagreeing without fear. A study of surgical teams showed high performers report more errors, reflecting trust, not incompetence. In software, this translates to teams where questions spark learning, help fosters collaboration, and dissent drives improvement, creating dynamic, challenging environments that fuel innovation.
Growing as a Programmer
Personal growth sustains programming excellence. Daniel urged developers to stay current through communities, contribute actively, and remain skeptical of trends like AI hype. Practicing via challenges like Advent of Code sharpens skills, as Daniel found when switching languages mid-puzzle. Balancing work with physical activities, like running, and prioritizing rest prevents burnout. By embracing continual learning and kindness, programmers evolve, as Daniel’s colleague demonstrates, into impactful, resilient professionals.
Links:
[OxidizeConf2024] Continuous Compliance with Rust in Automotive Software
Introduction to Automotive Compliance
The automotive industry, with its intricate blend of mechanical and electronic systems, demands rigorous standards to ensure safety and reliability. Vignesh Radhakrishnan from Thoughtworks delivered an insightful presentation at OxidizeConf2024, exploring the concept of continuous compliance in automotive software development using Rust. He elucidated how the shift from mechanical to software-driven vehicles has amplified the need for robust compliance processes, particularly in adhering to standards like ISO 26262 and Automotive SPICE (ASPICE). These standards are pivotal in ensuring that automotive software meets stringent safety and quality requirements, safeguarding drivers and passengers alike.
Vignesh highlighted the transformation in the automotive landscape, where modern vehicles integrate complex software for features like adaptive headlights and reverse assist cameras. Unlike mechanical components with predictable failure patterns, software introduces variability that necessitates standardized compliance to maintain quality. The presentation underscored the challenges of traditional compliance methods, which are often manual, disconnected from development workflows, and conducted at the end of the development cycle, leading to inefficiencies and delayed feedback.
Continuous Compliance: A Paradigm Shift
Continuous compliance represents a transformative approach to integrating safety and quality assessments into the software development lifecycle. Vignesh emphasized that this practice involves embedding compliance checks within the development pipeline, allowing for immediate feedback on non-compliance issues. By maintaining documentation close to the code, such as requirements and test cases, developers can ensure traceability and accountability. This method not only streamlines the audit process but also reduces the mean-time-to-recovery when issues arise, enhancing overall efficiency.
The use of open-source tools like Sphinx, a Python documentation generator, was a focal point of Vignesh’s talk. Sphinx facilitates bidirectional traceability by linking requirements to code components, enabling automated generation of audit-ready documentation in HTML and PDF formats. Vignesh demonstrated a proof-of-concept telemetry project, showcasing how Rust’s cohesive toolchain, including Cargo and Clippy, integrates seamlessly with these tools to produce compliant software artifacts. This approach minimizes manual effort and ensures that compliance is maintained iteratively with every code commit.
Rust’s Role in Simplifying Compliance
Rust’s inherent features make it an ideal choice for automotive software development, particularly in achieving continuous compliance. Vignesh highlighted Rust’s robust toolchain, which includes tools like Cargo for building, testing, and formatting code. Unlike C or C++, where developers rely on disparate tools from multiple vendors, Rust offers a unified, developer-friendly environment. This cohesiveness simplifies the integration of compliance processes into continuous integration (CI) pipelines, as demonstrated in Vignesh’s example using CircleCI to automate compliance checks.
Moreover, Rust’s emphasis on safety and ownership models reduces common programming errors, aligning well with the stringent requirements of automotive standards. By leveraging Rust’s capabilities, developers can produce cleaner, more maintainable code that inherently supports compliance efforts. Vignesh’s example of generating traceability matrices and architectural diagrams using open-source tools like PlantUML further illustrated how Rust can enhance the compliance process, making it more accessible and cost-effective.
Practical Implementation and Benefits
In his demonstration, Vignesh showcased a practical implementation of continuous compliance using a telemetry project that streams data to AWS. By integrating Sphinx with Rust code, he illustrated how requirements, test cases, and architectural designs could be documented and linked automatically. This setup allows for real-time compliance assessments, ensuring that software remains audit-ready at all times. The use of open-source plugins and tools provides flexibility, enabling adaptation to various input sources like Jira, further streamlining the process.
The benefits of this approach are manifold. Continuous compliance fosters greater accountability within development teams, as non-compliance issues are identified early. It also enhances flexibility by allowing integration with existing project tools, reducing dependency on proprietary solutions. Vignesh cited the Ferrocene compiler as a real-world example, where similar open-source tools have been used to generate compliance artifacts, demonstrating the feasibility of this approach in large-scale projects.
Links:
[KotlinConf2019] A Vibrant Gathering of the Global Kotlin Community
KotlinConf 2019, held in Copenhagen, Denmark, from December 4-6, marked a significant moment for the Kotlin ecosystem, bringing together a passionate global community of developers, enthusiasts, and industry leaders. With over 1,600 attendees on-site and many thousands more joining via live stream, the conference was a testament to Kotlin’s burgeoning popularity and its expanding footprint across various domains of software development. The event, meticulously organized by JetBrains, the creators of Kotlin, served as a vibrant hub for knowledge sharing, networking, and celebrating the language’s latest advancements and future directions. The official Kotlin language website, a key resource for developers, is kotlinlang.org.
The atmosphere, as captured in highlight reels and attendee testimonials, was electric, filled with excitement and a shared enthusiasm for the language’s capabilities. Attendees praised the depth of technical talks, the relatability of the content to their daily work, and the motivating nature of keynote presentations that often held an element of suspense regarding new feature announcements. More than just a series of lectures, KotlinConf fostered a strong sense of community, a recurring theme in participants’ feedback, who often cited the community itself as one of the best parts of their Kotlin experience. This collective energy underscored Kotlin’s journey from a promising JVM language to a versatile tool impacting Android development, backend systems, web frontends, and multiplatform projects.
A Hub for Learning and Innovation
KotlinConf 2019 provided a rich learning environment, offering a diverse range of sessions that catered to various skill levels and interests. From in-depth explorations of Kotlin’s newest features to practical workshops and discussions on best practices, the conference was a platform for developers to enhance their skills and gain new perspectives. The content was designed to be both insightful and applicable, with many attendees noting the direct relevance of the talks to their ongoing projects and challenges. This focus on practical application, combined with a forward-looking vision for the language, made the event invaluable for professionals seeking to stay at the forefront of software development.
The conference also served as a crucial touchpoint for JetBrains to engage with the Kotlin community, gather feedback, and share their roadmap for the language’s evolution. This open dialogue is a hallmark of Kotlin’s development philosophy, ensuring that the language continues to meet the needs of its users and adapt to the ever-changing technological landscape. The excitement around new announcements and the opportunity to interact directly with the minds behind Kotlin added an extra layer of dynamism to the event, reinforcing its status as a premier conference for anyone invested in the Kotlin ecosystem. The success of such an event relies heavily on the engagement of its community, from the speakers sharing their expertise to the attendees bringing their curiosity and passion, all contributing to what many described as an “industrial revolution” in software development.