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Android Auto usually feels like a safe, well-patrolled neighborhood. Maps, music, calls, messages-no surprises, no rogue neighbors. But…

28 Jul 2026 6:30am GMT

If you miss the golden age of '90s psychological thrillers, don't hesitate-Netflix recently added a hidden gem starring…

28 Jul 2026 6:00am GMT

Look no further for all the latest Boba Story Lid Recipes. They are all right here!

28 Jul 2026 5:29am GMT

Posted by Andrei Shikov, Senior Software Engineer, Android Toolkit and Jonathan Starup, Software Engineer, R8 Team

Starting from AGP 9.2.0, R8 optimizes most Atomic*FieldUpdater calls into Unsafe variants that perform 2x to 4x better on common operations. This has a particularly large impact on the kotlinx.atomicfu library that implements atomics for kotlinx.coroutines, making launching and cancelling coroutines up to 2x faster. In order to get the benefits, update your AGP to 9.2.0 or above.

With the majority of Android apps adopting Kotlin as their main language of choice, kotlinx.coroutines has become a de-facto standard for asynchronous programming. The library offers a well-designed and structured way of managing concurrent flows that is native to Kotlin. Jetpack Compose was no exception, adopting coroutines for managing pointer events, animations and other interactions. At the time of writing, most concurrent APIs in Compose call suspend functions under the hood and are launching and/or cancelling coroutines to handle updates.

As the Compose team started to investigate performance, coroutines were discovered to be a bottleneck for many operations that happen outside of composition. As an example, 80% of the time spent on creating and updating Modifier.clickable was consumed by launching and cancelling internal coroutines that handled InteractionSource updates. Based on those observations, much of early performance work was focused on removing coroutines from the default path and delaying initialization until necessary.

The cost of a coroutine

The easiest way to analyze a function's internal behavior on Android is to capture an Android Runtime (ART) method trace. An ART method trace is a tool that records the execution flow of an app, showing exactly which methods are called, their order, and how much time is spent in each, allowing developers to identify performance bottlenecks. For an empty LaunchedEffect { } call, it would look something like this:

LaunchedEffect method trace visualized in the Perfetto UI

The method trace above can be separated into three parts:

• Initializing a new coroutine
• Starting coroutine
• Completing coroutine (because it exits immediately)

Cancelling LaunchedEffect is similar to normal completion, except it also creates a CancellationException.

From the profile above, one thing that is immediately suspicious is frequent calls into java.util.concurrent.AtomicReferenceFieldUpdater (purple or green boxes with j… labels). While each call is relatively fast, the frequency is concerning; any non-negligible overhead that is spread out across multiple invocations might add up to a noticeable regression. Zooming in on a call reveals that most of the time is spent on... reflection checks?

An up-close look at the method trace of AtomicReferenceFieldUpdater.get during LaunchedEffect initialization

Coroutines implement a lock-free tree structure for parent-child relationships that makes structured concurrency possible. Turns out, the kotlinx.atomicfu library implements lock-free atomic operations using a well-known JVM primitive, AtomicReferenceFieldUpdater. The updater uses a class reference and a field name to perform atomic operations at runtime, and it has to run several reflective safety checks to make sure the field exists and is accessible. Each operation in coroutines (starting, suspending, cancelling, completing) calls at least one atomic operation, so if it is slow, coroutines will not perform well.

Investigating AtomicReferenceFieldUpdater

But let's not get ahead of ourselves. AtomicReferenceFieldUpdater is actually well-optimized on JVM for over 10 years now, and method traces might capture overhead that is completely removed by a VM level optimization: just-in-time (JIT) or ahead-of-time (AOT) compilations. To verify performance, let's write a few benchmarks to measure the difference between atomic references from kotlinx.atomicfu and java.util.concurrent.atomic.

@RunWith(AndroidJUnit4::class)
class AtomicReferenceBenchmark {
    @get:Rule
    val benchmarkRule = BenchmarkRule()
    
    private val atomicReference = java.util.concurrent.atomic.AtomicReference(false)
    private val atomicRef = kotlinx.atomicfu.atomic<Boolean>(false)
    
    @Test
    fun atomicReference_compareAndSet() {
        benchmarkRule.measureRepeated { 
            atomicReference.compareAndSet(true, false)
            atomicReference.compareAndSet(false, true)
        }
    }

     @Test
    fun atomicRef_compareAndSet() {
        benchmarkRule.measureRepeated {
            atomicRef.compareAndSet(true, false)
            atomicRef.compareAndSet(false, true)
        }
    }

    /* measuring other methods from the method traces above */
}

Running this benchmark on a Pixel 5 (while ensuring AtomicReferenceFieldUpdater#compareAndSet is JIT compiled during warmup), yields the following results on Pixel 5 (API 33):

 50.7 ns  atomicReference_compareAndSet
135   ns  atomicRef_compareAndSet

The measurements confirm the gap, with kotlinx.atomicfu version clearly being approximately 2.7x slower. This confirms that ART does not perform any hidden optimization and reflective access checks add real overhead during runtime.

Looking back at the original method trace, the only meaningful work performed by the AtomicReferenceFieldUpdater is the internal call into Unsafe.getObjectVolatile that actually executes the underlying atomic operation. In most cases, the updater initializer is static, and can be proved to be always correct based on the structure of the surrounding class. Thus, one could statically analyze most of the AtomicReferenceFieldUpdater usages and replace them with an internal Unsafe variant during compilation. It also just happens that Android build toolchain has its very own optimizing compiler that can do exactly that.

Optimization with R8

The Atomic*FieldUpdater classes support subtle, dynamic and reflection-based use, but are often used in statically obvious patterns. This both explains the slow baseline performance and the want for optimization. R8 is a full-program optimizing compiler and is well-suited to see through the simpler patterns to skim the overhead of the reflective safety checks. R8 receives JVM bytecode after the Java or the Kotlin compiler, but to ease readability these examples are presented in Java syntax. This is why there are no type arguments for AtomicReferenceFieldUpdater.

class Example {
    volatile String data = "";
    static final AtomicReferenceFieldUpdater updater =
        AtomicReferenceFieldUpdater.newUpdater(Example.class, String.class, "data");

    void example() {
        // ...
        updater.compareAndSet(this, "", "new");
        // ...
    }
}

The base example creates a static final updater which accesses a volatile field with simple constant arguments for the holder, the type, and the name of the field. The reflection used is totally transparent. It is clear to see this updater references a valid field and that the site of the updater creation has valid access to the field.

In its essence, Atomic*FieldUpdater is a wrapper around a field offset and calls to Unsafe. The best case scenario for the optimization is to replace the updater field with an offset field and replace the updater calls with calls to Unsafe.

Optimizing Atomic*FieldUpdater

The optimization is implemented in three parts: Instrumentation, Replacement, and Clean-up.

Instrumentation

The first step is to introduce offset fields alongside the updater field in order to facilitate direct access via the Unsafe call.

static final long updater$offset =
    SyntheticUnsafe.UNSAFE.objectFieldOffset(Example.class.getDeclaredField("data"))

The field is accessed via reflection, and Unsafe is used to extract the field offset on the class. This code represents the internals of Atomic*FieldUpdater if you disregard reflection validation. Instead, the holder type of the updater and the field type of the volatile field are tracked statically in the compiler.

Note that the original field and its initialization are left as-is. The optimization process optimistically facilitates and optimizes uses and then later cleans up. This is a simple approach to the implementation but also allows partial optimization of updater fields, where some uses are left as they were while others are optimized.

Replacement

At this point in the compiler, after a suitable concurrency join point, we have a list of instrumented updater fields. This means that we can optimize each call site individually based on a few conditions. Consider an example call:

updater.compareAndSet(holder, expectedValue, newValue);

The conditions that Atomic*FieldUpdater requires are these:

• Does updater come from an instrumented field? That is, can static analysis track the value of the object back to a field read of an instrumented updater?
• Is holder the same class or a subclass of the originally defined holder type?
• Is newValue the same class or a subclass of the originally defined field type?

If all conditions are met, then the call is replaced by a call to Unsafe without any of the reflection checks.

SyntheticUnsafe.UNSAFE.compareAndSwapObject(holder, Example.updater$offset, expectedValue, newValue)

This new call is faster and simpler but it differs from the original call in regards to its handling of null values in updater and holder. Unless statically ruled out, null-checks are inserted for both.

Clean-up

At this point, the holding class has the original updater field and the new offset field along with call sites that might use either one of the two. If none of the call sites were optimized, then the offset field should be removed and if all of the call sites were optimized, then the updater field should be removed. In both cases the initializing call should also be deleted. The deletion of unused fields and removal of dead code is already done in the compiler, but removing the initializing code here requires a few more tricks.

Both the call to newUpdater and getDeclaredField might have side effects as they can throw exceptions (and their implementation is also unknown since it depends on the API version). This means that by generic optimization, they cannot safely be removed. So this clean-up required explicit consideration of the instrumented fields, since those are statically known to be free of exceptions.

In the end, the simple updater example shown above looks like this after optimization:

class Example {
    volatile String data = "";
    static final long updater$offset =
        SyntheticUnsafe.UNSAFE.objectFieldOffset(Example.class.getDeclaredField("data"))

    void example() {
        // ...
        SyntheticUnsafe.UNSAFE.compareAndSwapObject(this, Example.updater$offset, "", "new")
        // ...
    }
}

Results

After these optimizations, kotlinx.atomicfu and most explicit uses of AtomicInt/Long/ReferenceFieldUpdater now match AtomicReference performance with R8 applied. In fact, it is even faster in some benchmarks; kotlinx.atomicfu has a compiler plugin that can inline atomic instances into fields, reducing allocations required to create an atomically updated field.

Jetpack Compose was the main beneficiary of this work. Compose runtime has a number of microbenchmarks that track coroutine performance very closely to catch performance regressions early. When the benchmarks were updated to a new version of R8, we noticed a 2x improvement when launching and cancelling coroutines in LaunchedEffect!

Aside from that, the ART team is implementing these optimizations natively at the VM level. If your app is targeting API 37 and is running on a recent version of Android, it is possible that your device is already optimizing coroutines in a similar way. The coroutine benchmarks above observed ~15% improvement in performance after JIT updates in the recent versions of ART.

Your app will receive this optimization by default when upgrading to AGP 9.2.0 or by using R8 9.2.0 directly. For more information, see D8 dexer and R8 shrinker.

27 Jul 2026 1:00pm GMT

Posted by Fahd Imtiaz, Senior Product Manager and Miguel Montemayor, Developer Relations Engineer, Android Developer Experience

Today at Galaxy Unpacked, Samsung unveiled its latest lineup of foldable and wearable devices. For developers, this means that the variety of form factors, screen sizes, and device postures your app needs to support is expanding once again.

With devices like the Galaxy Z Fold8, the ecosystem is expanding to include hardware with a landscape-first natural orientation and a wider aspect ratio in its main display state. Whether a user is unfolding a large display, flipping open a cover screen, or glancing at their wrist, users expect a flawless experience. To help you meet this moment, we're sharing actionable guidance and new tooling updates to enable you to build adaptively proactively.

Rethink layout architecture for dynamic displays, including ultra-wide foldables

Building for the latest foldables means dropping assumptions about display orientation and size. This is especially true for the Galaxy Z Fold8, which adopts an ultra-wide display, adding to the variety of aspect ratios to account for. Devices with this landscape-first natural orientation show the limitations of hardcoded layout rules when users unfold the device. That's why we've introduced dedicated guidance for building for landscape foldables and trifolds.

To build a responsive UI that handles these physics seamlessly, focus on the following core pillars:

• Build fluid, adaptive layouts: Wide aspect ratios and compact vertical heights require fluid UIs that scale responsively. Our updated adaptive design guidance advises considering the window class width first to determine layout changes, then adjusting for height. To let individual components fluidly adapt to the grid, structure your layout using flexible containers that allow your content to automatically wrap, span, and reflow. For design inspiration browse our adaptive sample app and dual-screen design galleries.
• Track actual app space: Your app's display space rarely matches the physical device size, especially on an ultra-wide screen during multi-window, split-screen, or multitasking states. Sometimes even the orientations differ. Leverage Window Size Classes using the Jetpack Window Manager library to calculate the exact space your app occupies.

• Leverage the latest Jetpack Compose Update: Start by adopting the stable Jetpack Compose April '26 release (Compose BOM version 2026.04.01).Take advantage of the new structural layout tools to manage complex architectures. The new Grid API allows you to define dynamic tracks and column spans without the performance overhead of a lazy list. Pair Grid with the new FlexBox layout API to easily handle multi-axis alignment and dynamic item wrapping. You can also use the new MediaQuery API to adapt your UI to its environment, using conditions to detect signals like device posture, window size, and keyboard types.
• Make your app fold aware: Use the Jetpack WindowManager library, which provides an API surface for foldable device window features such as folds and hinges. When your app is fold aware, it can adapt its layout to avoid placing important content in the area of folds or hinges and use folds and hinges as natural separators.
• Maintain app continuity: Avoid breaking the user journey when the device configuration shifts. Retain your UI state using ViewModel to ensure smooth transitions when a user folds or unfolds their device.

Ensure seamless camera capture on foldable devices

Camera implementation on foldables brings unique hardware quirks. Moving from a compact outer display to an expanded inner display introduces distinct layout aspect ratios while device rotation remains unchanged. If an app assumes a fixed portrait relationship between the camera sensor and the device layout, the app will likely suffer from sideways, stretched, or cropped previews during these folding transitions.

When optimizing your app's media pipeline, migrate your capture experiences to CameraX using the CameraX migration skill. The library's PreviewView automatically handles sensor orientation, device rotation, and scaling behind the scenes. This guarantees a clean, stable preview regardless of how the user holds or positions the device. If you are maintaining an existing Camera2 codebase, integrate the CameraViewfinder library to apply these complex aspect ratio and rotation transformations automatically without needing a total architecture overhaul.

Extend glanceable interactions to Wear OS 7

The opportunity to build for this new generation of devices extends right to the wrist. Launching with Wear OS 7, Wear Widgets give you a fresh surface to provide users with instant, glanceable access to their essential updates. You can build these highly expressive experiences using Jetpack Glance and RemoteCompose. Crucially, Widgets built with this framework can now populate multi-widget tiles that were previously reserved for first-party widgets.

Build intelligent features

Gemini intelligence already completes tasks on users' behalf, and you can experiment with the intelligence system by sharing your apps capabilities.

Samsung's new foldable devices come with Gemini Nano 4, our latest on-device model. Nano 4 provides support for over 140 languages, better multimodal understanding, and much more. Use ML Kit's Prompt API with advanced features like structured output and thinking mode to build intelligent features on-device.

Start optimizing today

The tools and frameworks are ready to help you optimize your app for all screen sizes. Begin by exploring our guidance for building adaptive apps to learn more about core adaptive design principles.

To dive deeper, check out our comprehensive YouTube playlist. Finally, ensure your app delivers a flawless, premium experience on the newest form factors by reviewing our dedicated quality guidelines for trifolds and landscape foldables and WearOS.

Unfold the future today!

22 Jul 2026 7:00pm GMT

Welcome back to the blog post series "Build intelligent Android apps" where we take a basic Android app and transform it into a personalized, intelligent, and agentic experience. In our previous post we introduced Jetpacker, the demo app we'll use throughout this series.

In this blog post, we will share how you can use Gemini Nano through ML Kit's Prompt API to build intelligent on-device features.

Building intelligent on-device features refers to the ability to process prompts and data directly on a device without sending data to a server. This offers a few advantages:

• User data can be processed locally on the device, preserving user privacy
• Functionality of the model is reliable even with spotty or no internet connection
• No additional cloud inference cost, since everything runs on the user's hardware

With the benefits of on-device in mind, we identified three features to add in Jetpacker that can improve the user experience: summarizing trip itineraries, managing expenses, and capturing voice notes.

On-device features in Jetpacker: Summarizing trip itineraries, managing expenses, and voice notes

High quality tailored summarization of short texts

The itinerary screen gives users a quick overview of all activities for a given trip. Since this screen contains a lot of information, it can quickly become overwhelming. To help users prepare without feeling overwhelmed, we can add a 'Get ready for your trip' section at the top.

The romantic Paris trip is summarized as a classic Parisian adventure blending art, sights, and delicious food. A tip and some useful phrases are also added.

By inputting a trip itinerary and asking an LLM to summarize it, we can generate a quick summary of the trip along with packing tips and useful local phrases. This is a great use case for an on-device model for several reasons:

• Performance and quality: Both the input and output text are relatively short. With that, we can expect the performance and quality of an on-device solution to be on par with more powerful cloud models.
• Scalability: Shifting inference on-device allows us to scale this feature from a few users to millions without worrying about managing increasing cloud inference costs.
• Low latency and reliability: On-device inference guarantees low latency, providing a reliable experience even when users are offline.

To build with on-device, we use Gemini Nano, Google's most efficient model optimized for mobile devices. Gemini Nano was first introduced a few years ago, and is now running on over 140 million devices. The latest version of the model, Gemini Nano 4, is built on the architecture foundation of the recently released Gemma 4 model, and is further optimized for maximum battery and performance efficiency.

Using ML Kit's Prompt API, we can take advantage of Gemini Nano 4's new model capabilities to prototype our on-device features. We'll create a prompt that includes the itinerary of a trip and ask the model to generate a summary along with any preparation tips.

// implementation("com.google.mlkit:genai-prompt:1.0.0-beta3") 

// Define the configuration for Gemini Nano 4 E2B preview model
val previewFastConfig = generationConfig {
    modelConfig = modelConfig {
        releaseStage = ModelReleaseStage.PREVIEW
        preference = ModelPreference.FAST
    }
}

val geminiNano2BPreviewModel = Generation.getClient(previewFastConfig)

val tripItinerary = ...

val getReadyForYourTripSummary = geminiNano2BPreviewModel
 .generateContent("Given this trip itinerary: $tripItinerary, 
     generate the following: overall vibe, tips on how to prepare for this
     trip, and common short phrases to learn for the trip.")

Finding the optimal prompt usually requires some iteration, and the AICore app is perfect for this step in the process. After opting into the developer preview option for AICore, we can download preview models such as Gemini Nano 4 to test prompts and see the model's expected outputs. With a few iterations on the prompt, we were able to improve the speed of the response from 13 seconds to under 2 seconds! Check out the final code implementation and prompt here.

The first iteration of our prompt generated way too many tokens, and optimizing it helped keep responses quick and to the point.

Local processing for sensitive user input

Next, to help users enjoy their trip even more, we'll build a simple expense manager that takes the manual work out of sorting through receipts and calculating budgets.

Taking a photo of a restaurant bill, data is parsed and shown in the expense overview screen of the app.

Since receipts might contain sensitive information like credit card number and addresses, this is another great use case for an on-device solution. With on-device, users can be confident that private information will be processed locally on the device without any of their data being sent to the cloud.

In addition, Gemini Nano 4 has improved model capabilities for multimodality, especially for image understanding tasks like OCR and visual data extraction, making it a great solution for tasks like extracting information from receipts.

For this use case, the prompt will analyze an image of the receipt, and output information such as: a generated title, amount spent and category of the expense. To ensure the model outputs the information in the preferred format, we can use ML Kit's Structured Output API to seamlessly output a Kotlin data object that we define.

// implementation("com.google.mlkit:genai-prompt:1.0.0-beta3")
// ksp("com.google.mlkit:genai-schema-compiler:1.0.0-alpha1")

@Generable("Information extracted from an expense receipt")
data class ParsedReceipt(
  @Guide("Generated title for the expense less than 6 words. Based on restaurant or activity name.")
  val title: String,
  @Guide("Total amount of the expense. Look for values at the bottom and words like total or balance due.")
  val amount: Double,
  @Guide("Type of expense", enumValues = ["travel", "food", "shopping", "entertainment", "other"])
  val category: String,
)

val prompt = "Determine if the image is a receipt or expense. 
    If it is NOT a receipt or expense, output the text 'NOT_A_RECEIPT'.
    Otherwise, parse the receipt information."

val request = generateContentRequest(ImagePart(bitmap), TextPart(prompt)) {}
val requestWithStructuredOutput = generateTypedContentRequest(request, ParsedReceipt::class)

// Define the configuration for Gemini Nano 4 E4B preview model  
// When selecting models, you can specify which performance charactertists are most important
//  for your use case. Use ModelPreference.FULL when you want to prioritize reasoning power over speed. 
//  Use ModelPreference.FAST when complex logic is not required and latency is a priority.
val previewFullConfig = generationConfig {
    modelConfig = modelConfig {
        releaseStage = ModelReleaseStage.PREVIEW
        preference = ModelPreference.FULL
    }
}

val geminiNano4BPreviewModel = Generation.getClient(previewFullConfig)
val response = geminiNano4BPreviewModel.generateContent(requestWithStructuredOutput)
val parsedReceipt: ParsedReceipt? = response.candidates.firstOrNull()?.response

Multimodal input

Lastly, to help users record audio memos during the trip, let's build a fully on-device voice notes feature. Using ML Kit's Speech Recognition API, we'll enable users to record short voice notes that are automatically transcribed to text. With the transcribed text, we'll use ML Kit's Prompt API to identify which trip activity is associated with the recorded voice note, letting users easily recap their trip as they scroll through the trip's itinerary.

The Roman holiday itinerary shows voice note extracts.

The ML Kit GenAI Speech Recognition API allows you to transcribe audio content to text fully on-device using two distinct modes. Basic mode uses a traditional on-device speech recognition model and is available on most Android devices with API level 31 and higher. Advanced mode uses Gemini Nano to offer broader language coverage and better quality, and is currently supported on Pixel 10 devices.

For our feature we combine the Speech Recognition API with the ML Kit GenAI Prompt API:

// implementation("com.google.mlkit:genai-prompt:1.0.0-beta3")
// implementation("com.google.mlkit:genai-speech-recognition:1.0.0-alpha1")

val tripEvents = ... 

// Set up speech recognition
val speechRecognizerOptions =
    speechRecognizerOptions {
        locale = Locale.US
        preferredMode = SpeechRecognizerOptions.Mode.MODE_ADVANCED
    }
val speechRecognizer: SpeechRecognizer = SpeechRecognition.getClient(speechRecognizerOptions)

suspend fun transcribeVoiceNote(recognizer: SpeechRecognizer) {
    // Display partial text as the user is recording audio
    var partialTextResponse = ""

    // Display the full text once user is finished recording audio
    var transcription = ""

    val request: SpeechRecognizerRequest
        = speechRecognizerRequest { audioSource = AudioSource.fromMic() }
    recognizer.startRecognition(request).collect { response ->
        when (response) {
            is SpeechRecognizerResponse.PartialTextResponse -> {
                partialTextResponse = response.text
            }
            is SpeechRecognizerResponse.FinalTextResponse -> {
                transcription = response.text
                processAndCategorizeVoiceNote(transcription, tripEvents)
            }
        }
    }
}

fun processAndCategorizeVoiceNote(transcribedVoiceNote: String, events: List) {
    val prompt = "Given the voice note $transcribedVoiceNote
     and the following events for this trip: $events, rewrite this transcription
     to remove filler words. Then, identify which events from the
     list this rewritten transcription matches to."

     // Utilize ML Kit's Prompt API to process voice note and tag it with the relevant trip activities
     Generation.getClient().generateContent(prompt)
}

Conclusion

Using ML Kit's GenAI APIs, we were able to take advantage of Gemini Nano to develop fully on-device intelligent features for the JetPacker app, and provide an improved user experience without any additional cloud costs.

Check out the full source code for Jetpacker on Github, and watch the video Build Intelligent Android apps with Google's AI to learn more about how to integrate intelligent features directly into your app using on-device models, cloud-powered reasoning, and the latest agentic frameworks.

Learn more

Check out the other parts of this blog post series:

Part 1: Introduction of the app and a high-level overview.
Part 2 (this post!): On-device intelligence. Deep-dive into ML Kit's GenAI APIs and Gemini Nano to build privacy-first features like itinerary summarization, receipt parsing, and local audio processing.
Part 3: Hybrid and cloud reasoning. Explore how to use Firebase AI Logic to ground LLM answers in real-world data like Google Maps and web context.
Part 4: System integration. Integrating with the Android intelligence system using AppFunctions.
Part 5 (coming soon): In-app agentic workflows. Extend the app with an end-to-end booking assistant powered by A2UI and ADK.

Interested in more on Android Development? Follow Android Developers on YouTube or LinkedIn!

All code snippets in this blog post follow the following copyright notice:

Copyright 2026 Google LLC.
SPDX-License-Identifier: Apache-2.0

21 Jul 2026 1:00pm GMT

It all started innocently enough: sometime last summer, I ran into the blog post Start your own Internet Resiliency Club on Hacker News.

…communicate with each other across a few kilometers without any centralized infrastructure using cheap, low-power, unlicensed LoRa radios and open source Meshtastic text messaging software.

The idea of a local, infrastructure-free communications mesh sounded useful, especially as we were about to sail into the Pacific.

Meshtastic

While conflicts and natural disasters are hopefully far away, on the smaller atolls there is no cellular network. With Meshtastic we could communicate over LoRa.

Over the hurricane season, the Meshtastic setup became quite extensive. Our boat has a Meshtastic node, plus a mast-mounted solar repeater. We both have Meshtastic cards that we carry with us. With these we can communicate with text messages over quite a long distance. And we get telemetry and alerts from the boat.

In Cartagena, Colombia we could hear the boat pretty much across the city. And since some of our buddy boats also run Meshtastic, we've even had conversations while offshore.

While the existing Meshtastic setup is serving us well, there is always room for improvement and new ideas.

Reticulum

Reticulum is a project that seeks to take this to a whole new level. It is a whole decentralized networking stack that allows anything from instant messaging and voice calls to full-on SSH sessions to be carried over a multitude of different interfaces. You can transport Reticulum over LoRa, Bluetooth, and also over regular TCP/IP networks. And if authorities didn't take a dim view on encryption in ham radio, it would also work over our HF radio. With store-and-forward mechanisms it can deal with intermittent connectivity.

Because your identity is portable, your connectivity can be fluid. You can be sitting at a desk connected to a fiber backbone one moment, and walking through a field connected only to a long-range LoRa mesh the next. To the rest of the network, nothing has changed. Your friends do not need to update your contact info. The messages they send do not bounce back. The network senses the shift in the medium and reroutes the flow of data automatically.
You are no longer a stationary node in a fixed grid. You are a wanderer in a fluid medium.
- The Zen of Reticulum

As it stands now, Reticulum is still quite an early system with rudimentary and tech-heavy user interfaces. But that seems to be about to change: the Columba app for Android seems about as user-friendly as Meshtastic or something like Signal. There's a lot of potential in that once it reaches a stable version.

Distributed development over Reticulum

In the meanwhile, there is one aspect of Reticulum we developers can benefit from immediately: Distributed development. With it, any rngit node running on Reticulum can be your "GitHub". Git history, issue tracking, release distribution is already there.

I recently switched my various programming projects over. We have rngit running on the boat NAS, and VPS running a mirror behind more consistent connectivity. And for now I also mirror the work periodically to GitHub for backwards compatibility.

Reticulum for software

What I think is worthwhile to explore is having machines interface with Reticulum. Just like we can tell our boat to switch lights on via a Meshtastic message, we should be able to do the same with Reticulum. And maybe there should be a NomadNet "site" for the boat showing status of the various systems.

Going further, maybe boats could share chart data, depth soundings, weather information with each other over this. The promise of VDES, but built from the grassroots perspective.

And maybe things like NoFlo should be able to communicate over Reticulum? Reticulum implementations exist for multiple programming languages, but for this we'd need a JavaScript port.

There's still a lot to study and to think about. Watch this space. Last time I noted that something is interesting, it took me to a ten year rabbit hole.

0 0

04 Jul 2026 12:00am GMT

Now that 2025 is over, it's time to look back and feel proud of the path we've walked. Last year has been really exciting in terms of contributions to GStreamer and WebKit for the Igalia Multimedia team.

With more than 459 contributions along the year, we've been one of the top contributors to the GStreamer project, in areas like Vulkan Video, GstValidate, VA, GStreamer Editing Services, WebRTC or H.266 support.

In Vulkan Video we've worked on the VP9 video decoder, and cooperated with other contributors to push the AV1 decoder as well. There's now an H.264 base class for video encoding that is designed to support general hardware-accelerated processing.

GStreaming Editing Services, the framework to build video editing applications, has gained time remapping support, which now allows to include fast/slow motion effects in the videos. Video transformations (scaling, cropping, rounded corners, etc) are now hardware-accelerated thanks to the addition of new Skia-based GStreamer elements and integration with OpenGL. Buffer pool tuning and pipeline improvements have helped to optimize memory usage and performance, enabling the edition of 4K video at 60 frames per second. Much of this work to improve and ensure quality in GStreamer Editing Services has also brought improvements in the GstValidate testing framework, which will be useful for other parts of GStreamer.

Regarding H.266 (VVC), full playback support (with decoders such as vvdec and avdec_h266, demuxers and muxers for Matroska, MP4 and TS, and parsers for the vvc1 and vvi1 formats) is now available in GStreamer 1.26 thanks to Igalia's work. This allows user applications such as the WebKitGTK web browser to leverage the hardware accelerated decoding provided by VAAPI to play H.266 video using GStreamer.

Igalia has also been one of the top contributors to GStreamer Rust, with 43 contributions. Most of the commits there have been related to Vulkan Video.

In addition to GStreamer, the team also has a strong presence in WebKit, where we leverage our GStreamer knowledge to implement many features of the web engine related to multimedia. From the 1739 contributions to the WebKit project done last year by Igalia, the Multimedia team has made 323 of them. Nearly one third of those have been related to generic multimedia playback, and the rest have been on areas such as WebRTC, MediaStream, MSE, WebAudio, a new Quirks system to provide adaptations for specific hardware multimedia platforms at runtime, WebCodecs or MediaRecorder.

We're happy about what we've achieved along the year and look forward to maintaining this success and bringing even more exciting features and contributions in 2026.

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26 Jan 2026 9:34am GMT

Some years ago I had mentioned some command line tools I used to analyze and find useful information on GStreamer logs. I've been using them consistently along all these years, but some weeks ago I thought about unifying them in a single tool that could provide more flexibility in the mid term, and also as an excuse to unrust my Rust knowledge a bit. That's how I wrote Meow, a tool to make cat speak (that is, to provide meaningful information).

The idea is that you can cat a file through meow and apply the filters, like this:

cat /tmp/log.txt | meow appsinknewsample n:V0 n:video ht: \
ft:-0:00:21.466607596 's:#([A-za-z][A-Za-z]*/)*#'

which means "select those lines that contain appsinknewsample (with case insensitive matching), but don't contain V0 nor video (that is, by exclusion, only that contain audio, probably because we've analyzed both and realized that we should focus on audio for our specific problem), highlight the different thread ids, only show those lines with timestamp lower than 21.46 sec, and change strings like Source/WebCore/platform/graphics/gstreamer/mse/AppendPipeline.cpp to become just AppendPipeline.cpp", to get an output as shown in this terminal screenshot:

Cool, isn't it? After all, I'm convinced that the answer to any GStreamer bug is always hidden in the logs (or will be, as soon as I add "just a couple of log lines more, bro" 0 0

05 Dec 2025 11:16am GMT

I've mentioned some of my various retronetworking projects in some past blog posts. One of those projects is Osmocom Community TDM over IP (OCTOI). During the past 5 or so months, we have been using a number of GPS-synchronized open source icE1usb interconnected by a new, efficient but strill transparent TDMoIP protocol in order to run a distributed TDM/PDH network. This network is currently only used to provide ISDN services to retronetworking enthusiasts, but other uses like frame relay have also been validated.

So far, the central hub of this OCTOI network has been operating in the basement of my home, behind a consumer-grade DOCSIS cable modem connection. Given that TDMoIP is relatively sensitive to packet loss, this has been sub-optimal.

Luckily some of my old friends at noris.net have agreed to host a new OCTOI hub free of charge in one of their ultra-reliable co-location data centres. I'm already hosting some other machines there for 20+ years, and noris.net is a good fit given that they were - in their early days as an ISP - the driving force in the early 90s behind one of the Linux kernel ISDN stracks called u-isdn. So after many decades, ISDN returns to them in a very different way.

Side note: In case you're curious, a reconstructed partial release history of the u-isdn code can be found on gitea.osmocom.org

But I digress. So today, there was the installation of this new OCTOI hub setup. It has been prepared for several weeks in advance, and the hub contains two circuit boards designed entirely only for this use case. The most difficult challenge was the fact that this data centre has no existing GPS RF distribution, and the roof is ~ 100m of CAT5 cable (no fiber!) away from the roof. So we faced the challenge of passing the 1PPS (1 pulse per second) signal reliably through several steps of lightning/over-voltage protection into the icE1usb whose internal GPS-DO serves as a grandmaster clock for the TDM network.

The equipment deployed in this installation currently contains:

• a rather beefy Supermicro 2U server with EPYC 7113P CPU and 4x PCIe, two of which are populated with Digium TE820 cards resulting in a total of 16 E1 ports

• an icE1usb with RS422 interface board connected via 100m RS422 to an Ericsson GPS03 receiver. There's two layers of of over-voltage protection on the RS422 (each with gas discharge tubes and TVS) and two stages of over-voltage protection in the coaxial cable between antenna and GPS receiver.

• a Livingston Portmaster3 RAS server

• a Cisco AS5400 RAS server

For more details, see this wiki page and this ticket

Now that the physical deployment has been made, the next steps will be to migrate all the TDMoIP links from the existing user base over to the new hub. We hope the reliability and performance will be much better than behind DOCSIS.

In any case, this new setup for sure has a lot of capacity to connect many more more users to this network. At this point we can still only offer E1 PRI interfaces. I expect that at some point during the coming winter the project for remote TDMoIP BRI (S/T, S0-Bus) connectivity will become available.

18 Sep 2022 10:00pm GMT

Almost one year after my post regarding first steps towards a V5 implementation, some friends and I were finally able to visit Wobcom, a small German city carrier and pick up a lot of decommissioned POTS/ISDN/PDH/SDH equipment, primarily V5 access networks.

This means that a number of retronetworking enthusiasts now have a chance to play with Siemens Fastlink, Nokia EKSOS and DeTeWe ALIAN access networks/multiplexers.

My primary interest is in Nokia EKSOS, which looks like an rather easy, low-complexity target. As one of the first steps, I took PCB photographs of the various modules/cards in the shelf, take note of the main chip designations and started to search for the related data sheets.

The results can be found in the Osmocom retronetworking wiki, with https://osmocom.org/projects/retronetworking/wiki/Nokia_EKSOS being the main entry page, and sub-pages about

• Node Control Unit

• 16x BRI Uk0 Line Card

• 32x POTS Line Card

• Line Measurement Unit

• Shelf

In short: Unsurprisingly, a lot of Infineon analog and digital ICs for the POTS and ISDN ports, as well as a number of Motorola M68k based QUICC32 microprocessors and several unknown ASICs.

So with V5 hardware at my disposal, I've slowly re-started my efforts to implement the LE (local exchange) side of the V5 protocol stack, with the goal of eventually being able to interface those V5 AN with the Osmocom Community TDM over IP network. Once that is in place, we should also be able to offer real ISDN Uk0 (BRI) and POTS lines at retrocomputing events or hacker camps in the coming years.

08 Sep 2022 10:00pm GMT

If you have ever worked with Digium (now part of Sangoma) digital telephony interface cards such as the TE110/410/420/820 (single to octal E1/T1/J1 PRI cards), you will probably have seen that they always have a timing connector, where the timing information can be passed from one card to another.

In PDH/ISDN (or even SDH) networks, it is very important to have a synchronized clock across the network. If the clocks are drifting, there will be underruns or overruns, with associated phase jumps that are particularly dangerous when analog modem calls are transported.

In traditional ISDN use cases, the clock is always provided by the network operator, and any customer/user side equipment is expected to synchronize to that clock.

So this Digium timing cable is needed in applications where you have more PRI lines than possible with one card, but only a subset of your lines (spans) are connected to the public operator. The timing cable should make sure that the clock received on one port from the public operator should be used as transmit bit-clock on all of the other ports, no matter on which card.

Unfortunately this decades-old Digium timing cable approach seems to suffer from some problems.

08 Sep 2022 10:00pm GMT