Now attending

( 2025-04-25, 20:26)

 "Digital Public Goods - Incentivizing Collaboration"

Saturday at 17:35, 25 minutes, UB5.230, UB5.230, Community Mike Gifford

Digital Public Goods are often celebrated as open-source software, open data, open AI models, open standards, and open content. However, true public goods require more than openness—they demand active community governance, collective stewardship, and responsible contributions to thrive as shared resources.

While proprietary software sustains itself through licensing, support, and vendor lock-in, open-source software relies on a delicate balance of professional firms, organizational backing, and dedicated enthusiasts. The open model has fueled flexibility, innovation, and the global adoption of open technologies.

Yet, the rapid growth of "open" has not been matched by an equivalent rise in contributions or investments in maintenance. Discussions often prioritize licensing over the essential question: How do we, as a community, ensure that digital public goods are sustainable? This talk explores the responsibility of contributors, organizations, and users in building a resilient ecosystem for open technologies.

Coming up:

 "Version control is changing! BOF"

Saturday at 18:00, 60 minutes, AW1.121, AW1.121, BOF - Track A Raphaël Gomès

Let's chat about Git, Mercurial, Pijul, Jujistu... what makes them great or not so great and what they're currently doing to improve. Present in the room will be two Mercurial developers, the creator of Pijul and other people invested in this space, feel free to come, ask questions and bounce ideas!

 "Organizer's Panel"

Saturday at 18:00, 60 minutes, H.1301 (Cornil), H.1301 (Cornil), Legal and Policy Tom Marble Karen Sandler Bradley M. Kuhn Richard Fontana Matthias Kirschner Alexander Sander

Legal and Policy Issues Devroom Organizers discuss topics in the DevRoom.

 "The USB-MIDI 2.0 device class in Zephyr"

Saturday at 18:00, 25 minutes, H.1302 (Depage), H.1302 (Depage), Embedded, Mobile and Automotive iTitou

A few years ago, a musician friend of mine reached out, hoping to build a custom controller for a live act performance. Together, we decided on a USB-MIDI device, which soon became a hands-on learning journey into Zephyr, USB development, and the MIDI protocol.

MIDI (Musical Instrument Digital Interface) has been the leading standard for connecting digital instruments and controllers since the 1980s. Although USB includes MIDIStreaming (a subclass of the Audio device class), Zephyr had no support for it. So, I decided to build one.

In this talk, I’ll walk you through my adventures implementing (and eventually upstreaming) this new device class. We’ll start by revisiting the original MIDI 1 protocol from the eighties, the original USB-MIDI1.0 from the 2000s and the updated USB-MIDI2.0 specification from 2020. After a brief refresher on USB devices, I’ll introduce the USB MIDIStreaming interface and the various supported topologies. Finally, we’ll see how to bring it all together using Zephyr USB device_next, and how it is used from your application's code. In the end, we should be able to make any kind of MIDI speaking device using our favorite kite-stamped RTOS.

Alongside this technical content, I may relate my experience as an occasional hobbyist contributor since Zephyr 1.14, and how I navigated spec updates (Device tree changes, USB-MIDI 1.0 to 2.0, Zephyr USB device next).

 "Upstream Embedded Linux on RISC-V: The Good, the Bad and the Ugly"

Saturday at 18:00, 35 minutes, H.1309 (Van Rijn), H.1309 (Van Rijn), RISC-V Marcel Ziswiler

This talk looks at the state of upstream U-Boot, Linux kernel, FreedesktopSDK, and Yocto Project for the powerful SpacemiT K1-based Banana Pi BPI-F3. Nothing has been merged yet, but I took the various pieces posted on mailing lists or available as merge requests and gave them a spin. As a reference for comparison, I also looked at the vendor downstream stuff available from Banana Pi Team/SpacemiT.

 "The Big FOSDEM Quiz of the Year"

Saturday at 18:00, 50 minutes, Janson, Janson, Keynotes Steven Goodwin

How much do you know about Free Software, Open Source, Developers, and European meetings?

We interrupt your regularly scheduled programming to bring you a lively TV-style quiz show featuring several rounds of questions deemed too geeky for TV - about kernels, software projects, and digital culture. (Some will offer mass audience participation!)

As a fun game it will separate the Red Hat's from the Red Star's, the Linus Torvalds from "some random person in Nebraska", and is a fantastic way to enjoy our community even more.

 "Databases in the AI Trenches"

Saturday at 18:00, 50 minutes, K.1.105 (La Fontaine), K.1.105 (La Fontaine), Main Track - K Building Bruce Momjian

Artificial intelligence use has exploded, with much anticipation about its future. This talk explores many of the advances that has fueled this explosion, including multi-dimensional vectors, text embeddings, semantic/vector search, transformers, generative AI, and Retrieval-Augmented Generation (RAG). The talk includes semantic/vector search and rag examples. It finally covers how the valuable data stored in databases can be used to enhance AI usage.

 "CRC detection and optimization"

Saturday at 18:00, 20 minutes, K.3.201, K.3.201, GCC (GNU Toolchain) Mariam Arutunian Hayk Aslanyan

Cyclic redundancy check (CRC) is a widely used error-detection mechanism that helps in the validation of data communication and storage in the digital world. While traditional bitwise implementations are slow and less efficient, alternative methods such as lookup tables, carry-less multiplication, and hardware CRC instructions offer significant performance improvements. In this talk, I will present a novel method for automatically identifying and replacing inefficient bitwise CRC implementations with optimized alternatives. The approach uses fast detection of candidate code fragments, symbolic execution for validation, and automatic replacement with more efficient implementations. The method is implemented in the GCC compiler as a separate pass and is open-source available. Experimental evaluation was performed for i386, AArch64, and RISC-V architectures, and the results demonstrated up to 91%, 98%, and 93% performance improvements respectively, highlighting the effectiveness of the proposed optimization.

 "Five silly things to do when benchmarking your BPF program"

Saturday at 18:00, 20 minutes, K.4.201, K.4.201, eBPF Dmitrii Dolgov

The Hitchhiker's Guide to the Galaxy has following to say about benchmarking: avoid, if at all possible. One of the reasons is that it's hard and often counterintuitive, another -- it attracts Ravenous Bugblatter Beasts.

Despite all those dangers it's still an important and underappreciated topic, and in this talk I would like to discuss cases when unexpected results arise from benchmarking of BPF programs and why they could be important. Kernel selftest benchmarks would serve as an example, but we will vary the load generation to produce different arrival distributions, introduce contention on tracepoints, or simulate swarm of network connections in user space. To make it easier, we will use home-grown tool Berserker, which was created with an intent to exercise real world BPF applications.

 "Distributed Tracing in Server-Side Swift"

Saturday at 18:00, 20 minutes, K.4.401, K.4.401, Swift Moritz Lang

This talk will provide an overview of observability in server-side Swift, with a focus on Distributed Tracing. I’ll start off by talking about some of the design decisions that went into building the swift-distributed-tracing library, which I co-created as part of Google Summer of Code in 2020. The talk will not only compare it to other Swift observability libraries (swift-log, swift-metrics), but also highlight some of the differences between Distributed Tracing in Swift compared to other ecosystems. My personal highlight is the fact that we eliminated the need for support libraries such as “OTel instrumentation for this specific web framework” by implementing swift-distributed-tracing to be used by libraries directly. During the next part, I’ll cover what it means to build a tracer implementation for swift-distributed-tracing with plenty of examples from my OpenTelemetry client swift-otel. I’ll finish the talk with an end-to-end example of a server-side Swift application using the Hummingbird web framework, fully instrumented using Logging, Metrics, and Distributed Tracing, including context propagation and log correlation. This example exports logs, metrics, and spans via the OpenTelemetry Protocol (OTLP) to both a standalone OTel Collector instance and other observability backends that support OTLP natively.

Links: - GitHub: apple/swift-distributed-tracing - GitHub: slashmo/swift-otel - OpenTelemetry Website

 "Delta Chat, from e-mail messaging to Peer-to-Peer realtime networking"

Saturday at 18:00, 30 minutes, K.4.601, K.4.601, Modern Email Xenia

Over the years, Delta Chat has matured to be an easy-to-use, secure, and even fast messenger for all platforms, based on the massive e-mail server network. We'll give an overview of the ways Delta Chat is used today and how it is developed by a dozen active contributors. This talk will highlight our recent introduction of realtime chat-shared apps that use e-mail OpenPGP-encrypted messaging to establish a private Peer-to-Peer network among chat group members. In this talk we will demonstrate how these apps work in real-time. We'll also report on several interesting situations where Delta Chat is used today in context of partial shutdowns or strict internet censorship.

Description:

In the beginning, Delta Chat was a fun little experiment, an experimental solution to the network effects problem: “nobody uses secure messengers! But everyone has E-Mail… 🤔" Since then it has come a long way. From a cross-platform set of messenger apps with freely chosen e-mail servers to using audited and well analyzed end-to-end encryption, our project is based on IETF and W3C approved protocols and specifications. We interoperate with the massively distributed SMTP e-mail routing network as well as other e-mail based apps or webmailers and socially are in collaborative relations with numerous other projects, including XMPP-based messengers and standardization specialists.

Delta Chat was among the first messengers to adopt Rust (2019) as its core implementation language and provide all-platform apps. Together with XMPP-projects like Cheogram and Monocles we are evolving a new paradigm and quasi-standard called "webxdc" that enables integration of web apps into chat groups, giving users full control over app distribution. Webxdcs provide a unique Peer-to-Peer model for deploying collaborative standards based software.

 "Mobilizon: Decentralizing Event Management for a Privacy-Respecting Social Web"

Saturday at 18:00, 30 minutes, UA2.118 (Henriot), UA2.118 (Henriot), Social Web Stéphane Alexandra

Mobilizon is a decentralized, privacy-focused platform for event management and group organization. In this talk, we will explore how Mobilizon empowers users to create and manage events without sacrificing their privacy or control over their data. We will discuss the importance of decentralization, provide a technical overview of the platform, and share insights into its growing community and future roadmap.

 "Hunting for GitHub Actions bugs with zizmor"

Saturday at 18:00, 30 minutes, UB4.132, UB4.132, Security William Woodruff

Much of the world's open source lives on GitHub, and uses GitHub Actions to provide tasks ranging from routine testing to critical build and release processes. As such, the security of GitHub Actions (and the workflows and actions that users develop and consume) is paramount to the security of the world's software.

But how secure is GitHub Actions, really? This talk will introduce GitHub Actions' internal building blocks and (mostly implicit) security model, and provide real world examples of security failures and surprising avenues of exploitation that recur in widely used actions and workflows. These examples will be motivated via zizmor, a Rust-based static analysis tool for GitHub Actions that can catch many of the most common (and severe) footguns that occur when writing workflows.

Attendees will leave knowing more about GitHub Actions security and best practices for writing secure workflows, as well as how to use zizmor both locally and in CI to detect potential security issues. No prior familiarity with GitHub Actions is necessary.

 "Go Lightning Talks"

Saturday at 18:00, 60 minutes, UD2.120 (Chavanne), UD2.120 (Chavanne), Go Maartje Eyskens

Come speak! As every edition the last hour of the Go Devroom will be open for 5 minute lightning talks. The CfP for this will open shortly before the event and close 90 minutes before the session starts.

 "Unpick performance mysteries benchmarking GraalVM native executables"

Saturday at 18:00, 25 minutes, UD2.208 (Decroly), UD2.208 (Decroly), Free Java Galder Zamarreño

Java code that is ahead-of-time (AOT) compiled using GraalVM Community Edition native-image may run more slowly than code that is just-in-time (JIT) compiled with the HotSpot compiler. This is something I quickly discovered when I joined the GraalVM team at Red Hat.

Diagnosing performance issues in Java code can be done using Java Microbenchmark Harness (JMH), which helps developers build, run and analyse microbenchmarks written in Java. However, it only works with Java virtual machines using JIT compilation. For the past four years I’ve been wondering how to make JMH achieve the same objectives when that Java code runs as GraalVM native executables.

Eventually I solved this problem creating an extension to JMH that allows Java developers to seamlessly run their existing JMH benchmarks as GraalVM native executables. In this talk I will demonstrate how to obtain benchmark results, gather performance statistics and inspect annotated assembly code. Finally I will compare how the GraalVM native-image AOT code differs from the JIT code of HotSpot.

 "Refining the Release Strategy of a Custom Linux Distro"

Saturday at 18:00, 25 minutes, UD6.215, UD6.215, Testing and Continuous Delivery Andreea Daniela Andrisan

As with many stages of the software development lifecycle, the release process needs to be constantly improved, iteration by iteration. This way, the software product gets delivered faster and more reliably to customers. This paper focuses on different techniques that have shortened the release cycle of the Kuiper Linux distribution. The new release process involves creating a stabilization branch from main which is dedicated to the new release. Previously, the software components were built and installed during the image creation. Now they are released independently as Debian packages which are uploaded on Analog Devices' Linux Package Repository. This is an easy, user-friendly method that facilitates the distribution and installation of ADI software packages. Each software component has its own release cycle so that one component's bugs won't affect the other components' release. The software components are tested both separately and integrated into the Kuiper image. The latter required creating a Kuiper Docker image. This ensures that each software component is compatible with the target system as early as possible in the development process.

 "Writing about FreeBSD"

Saturday at 18:05, 25 minutes, AW1.120, AW1.120, BSD Tom Jones

As a project we have notoriously great documentation. The handbook and man pages make it easy to find out how to do anything you might want to on a FreeBSD system, whether it is setting up a network or debugging kernel locking.

Explaining the changes we make to improve FreeBSD? We are less good at communicating what we are up to.

For the last 6 months I have been writing regular status reports about changes in the FreeBSD network stack using a tool guided approach to automate finding and managing what to write about.

In this talk I’ll explain how I am trying to improve communication around FreeBSD development and how you can get involved in writing about FreeBSD.

 "AI for Meetings"

Saturday at 18:05, 15 minutes, K.3.601, K.3.601, Real Time Communications (RTC) Tudor Avram Răzvan Purdel

This is the story of how Jitsi's AI evolved and expanded its features while keeping it all open source: from half-botched PoCs in a weekend to features our customers use in production on a daily basis. Razvan will walk you through some of the implementation details and gotchas of the near-real-time transcription system, while Tudor will guide you through all the other goodies which rely and expand on it.

 "Distributed Databases: Essential or Optional?"

Saturday at 18:05, 15 minutes, UA2.114 (Baudoux), UA2.114 (Baudoux), Cloud Native Databases Peter Zaitsev

In the era of distributed systems, many modern databases are designed to scale horizontally from the ground up. Yet, some of the most widely used databases, like MySQL and PostgreSQL, remain single-node by design, relying on third-party sharding solutions like Citus or Vitess for distribution. This raises a critical question: do we always need to go distributed, or can replicated single-node databases meet most use cases? In this talk, we’ll explore the trade-offs between distributed and non-distributed architectures, evaluate the limits of single-node databases, and discuss when it truly makes sense to embrace distribution. Join us as we navigate the complexities of modern database design and uncover what’s best for your applications.

 "Yet another new SDR runtime?"

Saturday at 18:05, 55 minutes, UB2.147, UB2.147, Radio Daniel Estévez

I will present some work-in-progress/experiments on a high-performance graph-based SDR runtime that differs from popular runtimes such as GNU Radio and FutureSDR in that instead of using circular buffers to connect adjacent blocks, the data travels in packets through closed circuits encompassing multiple blocks of the flowgraph. I show benchmarks comparing GNU Radio 3.10, GNU Radio 4.0, FutureSDR, this new runtime, and a hand-written ad-hoc implementation, for a class of certain simple flowgraphs. These show that popular runtimes often have a high overhead and that there is much room for improvements in performance. This project focuses on ARM Cortex-A53 CPUs, found in AMD RFSoC/MPSoC and other embedded platforms, but most ideas are applicable to other systems, including fast x86_64 machines.

 "Adventures in oxidizing Arch Linux Package Management"

Saturday at 18:05, 40 minutes, UB2.252A (Lameere), UB2.252A (Lameere), Rust David Runge

In 2023 a small set of developers set out to work on a Rust-based framework for Arch Linux Package Management (ALPM) - see talks from FrOSCon 2023 and All Systems Go! 2023. After months spent on securing funding for the work ahead, in late 2024 the project has picked up work again in an extended capacity.

In this talk we will explore the technical challenges this project seeks to overcome and provide an overview of the work ahead. This will cover topics such as the writing of specifications for custom file types, dedicated metadata file parsers and writers, the design of libraries for package handling, the more generic verification of digital signatures for distribution artifacts and the integration with existing and upcoming package building and package management infrastructure.

 "Developing Custom UIs to Explore Graph Databases Using Sigma.js"

Saturday at 18:05, 30 minutes, UB5.132, UB5.132, Data Analytics Alexis Jacomy

Visual exploration of graph databases is a powerful method for spotting signals and patterns not immediately visible in raw data. However, most existing tools are either too complex or heavy for business users or locked behind proprietary platforms. In visual network analysis, this complexity overload is a significant issue; while graph abstraction is powerful, it can also harm user experience if not properly managed. In this context, developing custom visual graph exploration user interfaces can be key to providing business users with workable tools.

I will present how to use sigma.js, an open-source JavaScript library for web-based network visualization, to write a dedicated web interface to explore data from RICardo, an open-data research project mapping world trade in the 19th century.

 "Become a Hiro"

Saturday at 18:05, 25 minutes, UB5.230, UB5.230, Community Addie Girouard

Over 30 years ago, Neal Stephenson wrote about a pizza-delivering hacker who saved the digital world. Today, we're all facing our own L. Bob Rife – not through ancient Sumerian viruses, but through corporate consolidation and regulatory pressure threatening to end open source as we know it.

Our digital commons began as a frontier of freedom and innovation. Today giants are consolidating control over the infrastructure that shapes our digital world. The dark future seen in the franchise-owned streets of Snow Crash's America is coming. But Hiro showed us how to fight back: with skill, with allies, and with unwavering dedication to freedom.

We're facing our own daemon – not ancient Sumerian, but modern corporate and regulatory control. The question is: Will you remain a pizza delivery driver, or will you become a Hiro?

The future of open source depends on your answer.

 "Research Software, Sustainability, and RSEs"

Saturday at 18:10, 25 minutes, AW1.126, AW1.126, Open Research Daniel S. Katz

Research software projects often are initially funded by a grant that supports development of the software. But when the grant ends, the projects have to shift to another model to support the required software maintenance, if the software is going to continue being used. This talk will look at the Parsl project and its effort to become sustainable, across a set of project phases. It will also look at the different kinds of RSE work that have taken place during the project. These activities, phases, and developer types appear to be useful concepts for planning or studying other research software projects, or research software as a whole.

 "D4C: Leveraging Delta Encodings for Faster and Lighter Container Image Updating."

Saturday at 18:10, 20 minutes, UD2.218A, UD2.218A, Containers Naoki Matsumoto

Container images sometimes take tens to hundreds of megabytes in size and require many network resources to be transferred. Especially in low-bandwidth network environments like edge computing, frequent image updating will be difficult and increase the network cost. In this talk, I will present "D4C", a software that provides faster and lighter image updating with delta encodings. Delta encodings reduce data size, but generating and applying deltas is a time-consuming operation. D4C utilizes some techniques to reduce them including merge-based delta management and applying deltas lazily. D4C reduces the data size to update images by up to 95% and provides about 10x faster updating in low-bandwidth networks than the state-of-the-art approach. Benchmarks with PostgreSQL and PyTorch showed that their performance degradation caused by D4C is negligible.

 "How hard is it to bring a professional level, sustainable, advanced CMS to market?"

Saturday at 18:15, 10 minutes, H.1308 (Rolin), H.1308 (Rolin), Collaboration and Content Management Michael Diedrick

We started building CMSes before the days of Wordpress, and we’ve built new CMS every five years or so since. In 2020, hunkered in my covid quarters, I wanted to devise the next version that had a hosted version, a self-hosted, more customizable version, and an open source version.

Kentico’s Petr Palas wrote a treatise in 2017 on why we shouldn’t build a new CMS. His essay basically considers custom CMSes a way to lock in clients, and suggests cloud-first headless CMSes were the future. I, as well, have built multiple versions of custom CMSes, but I see it quite the opposite – even 8 years later, now is exactly the time to create a new CMS.

In this talk I’m going to show the process, roadmap, dangers and successes of creating a content management system from the ground up. I’m going to talk through each of the parts, including errors and notification systems, issues and help systems, user and permissions systems, etc. I’m going to cover the many “required” layers of development that we just didn’t need that saved us thousands of hours and acquired a fraction of the technical debt.

 "CANCELLED - Mobian, "upstream first", and the Greater Good"

Saturday at 18:15, 20 minutes, H.2214, H.2214, FOSS on Mobile Devices Arnaud Ferraris

Mobian is a Debian derivative targeting mobile devices, and a significant actor in the Mobile Linux community. Its developers try to closely follow the Debian development cycle and expect to release the next Mobian stable version, codenamed "Trixie", around mid-2025.

However, packaging software and releasing disk images is merely the tip of the iceberg, with the most important work happening behind the scenes: testing, identifying and (hopefully) fixing bugs, contributing to upstream projects...

This talk will discuss the latest developments in Mobian, using it as a pretext to dive into the philosophy underlying its development, and how it shapes not only the technical aspects of the distribution, but also our interactions with the wider Mobile Linux community.

 "POSIX Signals in User Space on the Redox Microkernel"

Saturday at 18:15, 20 minutes, UB4.136, UB4.136, Microkernel and Component-Based OS Jacob Lorentzon

Redox is a community-developed Unix-like operating system written in Rust, with the long term goal of being a microkernel-based alternative to its monolithic counterparts. To achieve this, Redox has been pursuing a "userspaceification" strategy of the POSIX-enabling logic in the kernel, into a runtime library. The most recent example of this is the ongoing POSIX Signals project, funded by NLnet.

This presentation will provide an overview of the Redox operating system and architecture. It will describe the technical details of the userspace signals implementation, challenges, and which parts that were kept in the kernel and why.

 "Honey, I shrunk DNSdist"

Saturday at 18:20, 25 minutes, H.2213, H.2213, DNS Remi Gacogne

As a DNS proxy with extensive support for DNS encryption protocols, DNSdist seemed like a very good choice to support DoT, DoH and DoQ on embedded devices running OpenWrt. This is the story of how we completely underestimated the challenges of the embedded world, and managed in the end to make DNSdist's footprint small enough to provide end-to-end, encrypted DNS service to your home.

 "Operating OpenStack Swift in real life"

Saturday at 18:20, 30 minutes, K.3.401, K.3.401, Software Defined Storage Seongsoo Cho

OpenStack Swift is the object storage component of OpenStack, unique in its ability to be deployed independently for object storage services.

In this session, I will share valuable insights and experiences gained from operating OpenStack Swift as a public cloud service over the past eight years. Compared to other projects like Ceph, OpenStack Swift has fewer documented use cases. This presentation aims to provide practical knowledge for those looking to build and manage object storage solutions using Swift.

The discussion will cover: • Key components of OpenStack Swift • Architecture design for public cloud services • Operational scenarios for scaling nodes and handling failures • Monitoring strategies for effective operating

Project Repo : https://github.com/openstack/swift

 "Writing a Minimal Scheduler with eBPF, sched_ext, and C"

Saturday at 18:20, 20 minutes, K.4.201, K.4.201, eBPF Johannes Bechberger

Today, eBPF is used for software-defined networking, observability, monitoring tools, and more. Previously, creating these was labor-intensive and had a high barrier to entry. With the new scheduler extensions, we can now add custom schedulers to this list. Sched_ext allows us to write schedulers with custom policies directly in eBPF. In this talk, we’ll develop a basic FIFO (First-In-First-Out) scheduler in C to show you how to get started with writing your own. If you’re interested in diving deeper into eBPF, join us for a quick hands-on intro to custom scheduling!

 "Unlocking Global Resilience using Cloud Native Distributed Datastore"

Saturday at 18:20, 10 minutes, UA2.114 (Baudoux), UA2.114 (Baudoux), Cloud Native Databases Mary Grygleski

In today's hyper-connected world, organizations demand database solutions that transcend traditional infrastructure limitations. This talk explores how distributed SQL databases (such as the open source based YugabyteDB) enable unprecedented global resilience and scalability. We'll dive into practical strategies for building fault-tolerant, geo-distributed systems that can withstand regional failures while maintaining data consistency and high performance.

Key insights include: * Architectural principles of cloud-native distributed databases * Multi-region deployment strategies * Automatic failover and self-healing mechanisms * Real-world implementation patterns

Open Source project that is being used in this talk: YugabyteDB

 "Collaborate using the Firefox Profiler"

Saturday at 18:20, 20 minutes, UA2.220 (Guillissen), UA2.220 (Guillissen), Web Performance Nazım Can Altınova

Tracking down performance issues can be tough, especially when you're not quite sure how to fix them and need to reach out to someone on your team for help. In this talk, we’ll explore how the Firefox Profiler not only helps identify performance bottlenecks but also makes it easy to collaborate with your team to find solutions faster.

We’ll show how to collect and analyze profiling data, spot key issues, and share your findings, so everyone can work together more effectively. We’ll go through real-world examples of how using the Firefox Profiler can streamline your debugging process and improve teamwork.

 "Debug fission - Separating debug symbols from executables"

Saturday at 18:25, 15 minutes, K.3.201, K.3.201, GCC (GNU Toolchain) Johan Herland

An introduction and exploration of how to separate debug information from C/C++ build artifacts in order to save space and time when building large codebases. Is it possible to have fast builds without stripping away debug symbols altogether? How would you integrate this into a larger build system?

After a quick introduction to debug symbols, we dive into various compiler and linker options to make an executable smaller without stripping away its debug capabilities. We compare multiple approaches for splitting debug symbols from executables, and demonstrate their pros and cons.

After looking at the details, we take a step back and show how to integrate these techniques into larger build systems like CMake and Bazel, where the effect of split debug symbols is much more noticeable.

 "A Universal and Stable API to Everything: XMPP"

Saturday at 18:25, 15 minutes, K.3.601, K.3.601, Real Time Communications (RTC) Jérôme Poisson (Goffi)

Nowadays, most services provide APIs with their own formats, and sometimes multiple versions, which may change over time. But there is a universal API, with an excellent track record of stability and backward compatibility: XMPP!

In this talk, I'll show how XMPP can be more than just an Instant Messaging protocol, and how it can be an extremely powerful tool to access almost anything, from third-party networks (IM, microblogging, etc.) to file sharing, automation (IoT), and more.

I'll briefly explain how the XSF (XMPP Standards Foundation) is organized, how specifications are created, and why having a large number of XEPs (we are now in the 500 series) is not a bad thing—quite the opposite.

Next, I'll discuss some mechanisms of XMPP and demonstrate how they can be applied to a wide range of use cases.

I'll also show that you can use XMPP without having to deal with XML—you can use JSON from your software or other layers.

XMPP is a fantastic toolbox that can help you do almost anything. Let's dive into it and explore how it can help you achieve things simply, efficiently, and quickly.

 "Building reliable and scalable apps with Distributed Actors"

Saturday at 18:25, 20 minutes, K.4.401, K.4.401, Swift Jaleel Akbashev

Swift Distributed Actors offers an exciting way for building reliable and scalable apps in Swift. In this talk, we’ll start with a quick introduction to Distributed Actors itself, and Cluster System—peer-to-peer cluster actor system implementation. I’ll share my journey of implementing a simple event-sourcing and Virtual Actors plugin for this system, demonstrating how these patterns simplify state management and enhance fault tolerance. We’ll explore a small example and will see how it scales and manages different failures.

 "Using embedded Rust to build an unattended, battery-powered device"

Saturday at 18:30, 25 minutes, H.1302 (Depage), H.1302 (Depage), Embedded, Mobile and Automotive Xabier Crespo Álvarez , slides

In late 2023, the Libre Space Foundation asked my company to develop an Open Source photometer—a device designed to help astronomers measure and understand sky quality. The goal was to create a community-friendly tool accessible to enthusiasts and professionals alike, with an ambitious vision of building a global, crowdsourced network of photometers. While the network is a story for another time, this talk focuses on the journey of designing and deploying the device itself.

After writing down the requirements, we realized that the architecture—comprising I2C sensors, a microcontroller, and WiFi connectivity—was relatively straightforward. This simplicity gave us the opportunity to explore new technologies. In particular, could we use Rust to build a robust, unattended, battery-powered device?

Fast forward to today: we have manufactured several hundred units and are collaborating with the Instituto de Astrofísica de Canarias, a leading research institute, to rigorously test the devices under challenging conditions. In this session, we’ll share the lessons learned during development, the hurdles we overcame, and how Rust has since become an integral part of our workflow.

 "Rethinking the Web CMS and Finding the Excitement"

Saturday at 18:30, 10 minutes, H.1308 (Rolin), H.1308 (Rolin), Collaboration and Content Management Michael Diedrick

In the eyes of a site editor or administrator, web content management systems haven’t really changed much in 20 years. They all seem so similar to each other and cover the same distance as to be wholly generic. If there’s innovation in CMSes, it seems to be more about architecture, marketing, SEO and templates and less about customizations, new ideas and administrator delight. The players haven’t changed much over the years, and the newer players seem mostly focused on monetization through scale and commerce.

What can we do as a community to rethink the humble web CMS and open new pathways and ideas that could make a web CMS exciting again? This talk hopes to open more questions than answers, drawing on my 25 years of experience working with and building CMSes, and will cover some potential ways to move the industry forward through collaboration, CMS data interoperability and collective innovation.

 "Chatmail server networks for anonymous end-to-end encrypted messaging"

Saturday at 18:30, 30 minutes, K.4.601, K.4.601, Modern Email missytake

In April 2024 Delta Chat introduced "instant onboarding" using chatmail servers leading to several 10K new users-per-day surges in geographies like Somalia, Russia, Mexico, Cuba and the US. There are currently 1-2 new chatmail servers per month and in 2025 we want to cover more of the planet, and will dicuss our plans for "zero-metadata" operations.

 "Running Mattermost on YugabyteDB"

Saturday at 18:30, 10 minutes, UA2.114 (Baudoux), UA2.114 (Baudoux), Cloud Native Databases Jesús Espino

Mattermost is an open-source collaboration platform that uses PostgreSQL for its database. As a developer heavily involved with Mattermost, I constantly explore new technologies. Recently, I came across YugabyteDB and decided to test it as a replacement for PostgreSQL. In this tech talk, I will share my previous experience with another distributed database and how it compares with my experience with YugabyteDB. Also, I will share the results of running load tests on Yugabyte and how it compares to regular Postgres.

 "Networked Journalism: Bringing long-form publishing to the Fediverse"

Saturday at 18:30, 30 minutes, UA2.118 (Henriot), UA2.118 (Henriot), Social Web John O'Nolan

In an era dominated by centralized platforms and algorithm-driven content, the open web's foundational principles of diversity and user autonomy have been overshadowed. John O'Nolan, founder and CEO of Ghost.org, will explore how Ghost is integrating ActivityPub to reconnect with the open web's ethos. This session will delve into the motivations behind adopting ActivityPub, the technical journey of embedding it into Ghost, and the anticipated impact on publishers and readers. Attendees will gain insights into the challenges and triumphs of this integration and understand Ghost sees the evolution of independent media and networked publishing.

Key Takeaways:

  • Understanding the significance of ActivityPub in journalism and publishing
  • Insights into Ghost's strategic and technical approach in integrating ActivityPub.
  • The anticipated benefits for publishers and readers within the Fediverse.
  • A vision for the future of open, interconnected web platforms.

 "Enhancing artifact security with GitHub Artifact Attestations"

Saturday at 18:30, 30 minutes, UB4.132, UB4.132, Security Fredrik Skogman

In the evolving landscape of software development, ensuring the integrity of build artifacts like container images is crucial. GitHub Artifact Attestations is an artifact signing solution and PKI built on open source software like TUF and Sigstore. In this talk, I'll discuss and demonstrate how to use Artifact Attestations to generate signed SLSA attestations, and verifying their origin and authenticity. By the end of this session, you'll have a good understanding of how open source tools like Sigstore, in-toto, SLSA and TUF can collectively strengthen the security of the software supply chain.

 "Understanding the GraalVM Native Image Build Process"

Saturday at 18:30, 25 minutes, UD2.208 (Decroly), UD2.208 (Decroly), Free Java Tom Shull

GraalVM Native Image is a popular tool for building standalone executables from Java applications. It is able to generate executables with fast startup time and low memory footprint through the use of a closed world assumption, constraints on dynamism, and many traditional compiler optimizations.

Unfortunately, Native Image's many advanced features can make its build process inscrutable to an inexperienced developer. It is hard to decipher how its many internal components (e.g. analysis, compiler phases, plugins, intrinsics, features, singletons, substitutions, etc.) work in concert and what assumptions must not be violated.

In this talk I will attempt to help make sense of the Native Image build process. I will first describe what components exist and how they interact with each other. Next, I will walk through a native image build and highlight key phases of the process. Finally, I will provide some practical tips to follow when trying to learn more about specific functionality within Native Image.

 "TuxWrangler: Image Wrangler"

Saturday at 18:30, 30 minutes, UD2.218A, UD2.218A, Containers Kavitha Daula Ethan Pullen

TuxWrangler is a framework designed to simplify the creation and management sets of containers, focusing on automation, scalability, and flexibility. Unlike Packer, which excels at building single "golden images" for immutable infrastructure, TuxWrangler is tailored for environments requiring multiple lightweight, highly-configured images, such as GEICO's. It automates dependency updates by dynamically fetching and locking versions from container repositories, reducing manual effort and ensuring consistency. With its centralized configuration management and integration with CI/CD pipelines, TuxWrangler streamlines complex workflows, automates testing, and publishes validated images efficiently.

TuxWrangler addresses use cases requiring dynamic updates and multiple image variations without duplicated build logic. Its ability to manage dependencies dynamically, scale configurations efficiently, and integrate seamlessly with DevOps ecosystems makes it ideal for modern, fast-paced environments.

We will present a demo of TuxWrangler, which is currently being used by us to solve our engineering needs. We will focus on its ability to simplify multi-image builds, automate dependency management, and integrate seamlessly with existing workflows. We would like to receive feedback from the community regarding its future iterations, ensuring TuxBake remains a valuable tool for evolving infrastructure needs.

 "Enhancing delivery using Kubernetes Gateway API and Istio"

Saturday at 18:30, 30 minutes, UD6.215, UD6.215, Testing and Continuous Delivery Sachin Kumar Singh

At DigitalOcean's internal platform team, we use a tool called docc to make deploying apps easier for our teams. It’s designed to hide the complexity of Kubernetes so teams can focus on getting their apps running without needing to understand Kubernetes itself.

When we deploy updates to applications, we usually use a simple method where old versions are replaced with new ones, one by one, over a short time. This works fine most of the time, but if the new version has bugs—causing slower performance or errors for users—this method doesn’t have a built-in way to catch those problems early or quickly switch back to the previous version.

To solve this, we’ve added safer deployment strategies like canary and A/B testing. These allow us to release updates more cautiously by directing only a small percentage of user traffic to the new version first. If everything looks good, we slowly increase the traffic. If not, we can automatically roll back quickly.

We achieved this by using tools like the Kubernetes Gateway API, Envoy proxy, and Istio to manage and control how traffic flows between different versions of an app. These tools work together to create a "service mesh," which helps us balance traffic and make deployment smoother and safer.

In this talk, we’ll share what we learned while setting this up and how it’s helping us ensure more reliable application updates at DigitalOcean.

 "FreeBSD audit source and other syslog-ng news"

Saturday at 18:35, 25 minutes, AW1.120, AW1.120, BSD Peter Czanik

FreeBSD is one of the most popular platforms to run syslog-ng. Recently, I was approached if we could add a FreeBSD audit source driver to syslog-ng. While developing a new C-based driver is not something we could do in the short term, thankfully, using the program() source of syslog-ng still allowed us to create a new source in just a few hours, including its documentation. From this talk, you can learn how the freebsd-audit() source was created and how you can also easily develop similar sources yourself. A few more FreeBSD specific developments will also be mentioned.

 "Applying the "Do No Harm" Principle to Open* Practices and Technology"

Saturday at 18:35, 25 minutes, AW1.126, AW1.126, Open Research Malvika Sharan

The "Do No Harm" principle, well-established in fields like medical research, healthcare, and humanitarian aid, has significant potential to improve the quality and reduce the negative effects of open research practices and technology.

As open research/science practices become a norm across different disciplines, it is important to identify, improve awareness of, and reduce its known or unintended negative impacts on people and their communities. While efforts like ethical source licenses (like the Do No Harm and Hippocratic License) are yet to become an acceptable legal pathway to enforcing responsible practices in open source, more general adoption and use of the "Do No Harm" will help account for societal and environmental implications of research and technology.

In this talk, I will introduce a “do no harm” framework to identify risks and develop actionable plans to mitigate the negative impacts of open research practices and technology. This framework examines the development and deployment of technology across four critical areas: the actors involved or affected, the dynamics and relationships within impacted communities, the economic realities faced by researchers, and environmental impact. Additionally, I will highlight practical methods for addressing the potential negative consequences of our work.

This session is designed for anyone involved in open source/science, including researchers, designers, contributors, developers, maintainers, and community members who seek to better understand and navigate the ethical challenges of open research and technology. Attendees will gain insights into global disparities in technology and explore how they can share responsibility to ensure their work promotes more equitable benefits by combining open practices with the do-no-harm principle.

 "postmarketOS: what is it and what's new?"

Saturday at 18:40, 20 minutes, H.2214, H.2214, FOSS on Mobile Devices Oliver Smith

A quick introduction to postmarketOS (Linux Mobile distro based on Alpine that has been ported to lots of devices by now!), as well as an overview of cool things we did throughout the last year or so. Also what we are up to :>

Source code: https://postmarketos.org/source-code/

 "An Introduction to Netkit: The BPF Programmable Network Device"

Saturday at 18:40, 20 minutes, K.4.201, K.4.201, eBPF Mike Willard

Introduced in kernel v6.7, the Netkit device is an eBPF-programmable network device designed with containers in mind. In this talk, I will go over the the basics of the Netkit device, and discuss the performance gains we have realized and challenges we faced when rolling out Netkit across millions of containers at Meta.

Open-source projects used in this talk: Linux Kernel. View the netkit driver source code here.

 "Migrating 3B rows to TiDB for a high-traffic application"

Saturday at 18:40, 10 minutes, UA2.114 (Baudoux), UA2.114 (Baudoux), Cloud Native Databases Sorin Dumitrescu

A short story about why & how Omniconvert migrated from MongoDB to TiDB, with no downtime, for an application serving 15-20k requests per minute. We will discuss the challenges that prompted the migration, why we chose TiDB, overview stress testing & performance evaluation of the application running on TiDB, as well as walk through the steps of the migration. And of course, highlight some lessons learned and the end-user perceived improvements.

 "Trusted boot with the Genode OS Framework"

Saturday at 18:40, 20 minutes, UB4.136, UB4.136, Microkernel and Component-Based OS Alice Domage

Alice will present Gapfruit's design of trusted boot in combination with a microkernel operating system built with the Genode OS framework on an i.MX8MP SoC. This presentation will cover the various building blocks involved, including TPM, u-boot, libraries, and supporting tools. It will also explore how these components integrate within a microkernel environment and the trade-offs we have faced.

 "Object-Capability Security with Spritely Goblins for Secure Collaboration"

Saturday at 18:45, 10 minutes, H.1308 (Rolin), H.1308 (Rolin), Collaboration and Content Management Juliana Sims

The object-capability security paradigm (ocaps) is a conceptually simple, efficient model for collaboration in mutually-suspicious contexts. Spritely is exploring concepts and building solutions in this space to solve real-world problems while encouraging the wider adoption of ocaps, including by working alongside other ocaps organizations and projects to define a standard protocol for intercommunication between ocaps systems. This talk will explain what ocaps is and why you should use it.

Our current model of collaboration is broken. Rather than basing our systems on granting consent, we base them on revoking authority. Ocaps inverts this model with its "if you don't have it, you can't use it" approach, facilitated by restricted means of exchanging authority. Meanwhile, the Object Capability Network protocol (OCapN) abstracts away transport mechanisms between objects while creating a security barrier with minimal overhead. Altogether, this ocaps ecosystem enables secure collaboration in mutually-suspicious contexts by emphasizing and enforcing a consent-based approach to information and authority exchange. Spritely is pioneering new tooling for ocaps with its Goblins library, which also serves as a model for other implementations; and has plans for solutions to problems like distributed storage, identity management, and even social networking.

 "Cross-platform JIT compilers with GNU Lightning"

Saturday at 18:45, 15 minutes, K.3.201, K.3.201, GCC (GNU Toolchain) Paul Cercueil

Writing a Just-In-Time (JIT) compiler is a complex task. For that reason, libraries like libgccjit were developed to ease the process; but most often than not, JIT compilers are written from scratch, and only target one or two architectures.

In this talk I am going to present GNU Lightning, a cross-platform library that can be used to generate machine code at run-time. I will present its strengths and weaknesses, how to use it, and why I decided to use it in my JIT compiler project.

 "A long, short history of realtime AI agents"

Saturday at 18:45, 15 minutes, K.3.601, K.3.601, Real Time Communications (RTC) Rob Pickering

Until a few months ago, the only working approach for connecting realtime AI agents to WebRTC streams and phone calls was to use lengthy pipelines of speech to text, agent orchestration, and text to speech, often using multiple machine learning models from commercial vendors. That has changed with new realtime speech to speech models, most famously the (closed) OpenAI advanced voice, but what are the open source ways to build these kind of systems? This talk walks through my experience with using 4 different projects to build functional systems which can use open source (open weights) models at their core. We will talk about how we have integrated Jambonz, Livekit, and Ultravox (Fixie.AI) within our Aplisay framework and what this allows us to do.

 "A Business Intelligence architecture for Social and Solidarity Economy."

Saturday at 18:45, 10 minutes, UB5.132, UB5.132, Data Analytics Jordi Isidro Llobet , slides

Social and Solidarity Economy (SSE) refers to a wide range of economic activities that aim to prioritize social profitability instead of purely financial profits. SSE organizations act guided by values ​​such as equity, solidarity, sustainability, participation, inclusion and commitment to the community, and are also promoters of social change.

There is a great diversity of entities in the Social and Solidarity Economy. Different types of activity, different sizes of the entity, different maturity of the IT teams, different quantity and quality of data, medium budgets, low budgets, etc. The SSE, like the rest of the companies, must also make decisions based on data.

Normally the budget of the entities of the SSE is reduced, for this reason, we must facilitate intercooperation to minimize costs without reducing functionalities. The architecture must also be adaptable to future changes within the same entity, without having to make major migrations or lose the work already done. And, of course, Social and Solidarity Economy 💓 Feee Software

We will set up a Business Intelligence architecture by exploring free software tools such as PostgresSQL, DBT, Airflow, Zulip, Superset, etc. to adapt to the needs of the SSE, and Ansible to facilitate replicability and inter-cooperation.

 "I Like To Move IT, Move IT - Replication in TiDB & MySQL"

Saturday at 18:50, 10 minutes, UA2.114 (Baudoux), UA2.114 (Baudoux), Cloud Native Databases Leandro Morgado

Replication is a cornerstone of modern database systems, enabling high availability, scalability, and seamless data transfer across environments.

In this talk, we’ll delve into the replication capabilities of TiDB and explore how they address real-world database challenges at Bolt, the fast-growing Estonian-based mobility company.

We’ll begin with an introduction to TiDB Data Migration (DM), which facilitates MySQL-to-TiDB replication. Through practical examples, we’ll demonstrate its role in migrating MySQL workloads to TiDB, including shard consolidation.

Next, we’ll highlight TiCDC (TiDB Change Data Capture), a powerful tool for real-time data streaming. We’ll explain how TiCDC captures changes in TiDB and replicates them to downstream systems such as TiDB, MySQL, Apache Kafka, and other services. Use cases include easily reversible TiDB version upgrades, cross-region high availability with standby TiDB clusters, and real-time Change Data Capture into Kafka.

Throughout the talk, we’ll share practical tips and scenarios, including simplifying database migrations, minimiing downtime during upgrades, and ensuring data integrity in complex workflows.

Whether you’re migrating from MySQL to TiDB, upgrading TiDB clusters, or building cross-region high availability environments, this talk will equip you with the knowledge and strategies to leverage replication as a powerful tool in your database operations.