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Monday, September 14
 

11:00 MDT

Composing the Future: Async Workflows with std::execution
Monday September 14, 2026 11:00 - 12:00 MDT
Software development has now shifted decisively to a distributed, asynchronous paradigm, in which engineers must manage code that may be executing on parallel threads, or on a different machine. Many mainstream programming languages have adapted themselves to this new world. For example, JavaScript has promises and async/await, Python has asyncio, Rust offers zero-cost async/await with compile-time safety, and Go built goroutines and channels as first-class primitives.

C++ developers face the same challenge but have been left without a standard solution. As a result, much production code remains stuck in “callback hell,” where control flow is inverted, error handling is duplicated at every level, and common patterns like "run A and B in parallel, and then combine results" must be hand-rolled every time.

This is not simply a matter of bolting async/await onto C++. Deterministic destruction, zero-overhead abstraction, and precise control over memory and lifetimes, these very properties making C++ powerful dictate that an async framework cannot rely on a garbage collector or managed runtime to paper over complexity. It must earn its place by working with the language's ownership model, not around it.

std::execution is C++’s answer to this problem. Introduced as part of C++ 26, it solves this through composable senders: lazy, type-safe descriptions of work that can be chained, branched, and parallelized before being submitted to an execution context. Like Swift's structured concurrency, std::execution enforces structured lifetimes so that async work cannot silently outlive its scope.

This talk aims to provide application developers with an introduction to the current proposal and give them a grounding in the fundamentals that can be applied in real-world applications. We will walk through several worked examples: from simple chains to parallel fan-out with error propagation, showing side-by-side comparisons with callback-based equivalents to make the advantages more concrete and relatable.

This talk assumes no knowledge of the std::execution framework and no expertise in async programming, though practical, real-world experience will certainly help ground the examples. Attendees will leave with a working understanding of the sender/receiver model, practical patterns they can use, and a clear picture of what structured concurrency means for C++.

Presenters
avatar for Alistair Fisher

Alistair Fisher

Alistair Fisher is an Engineering Team Lead at Bloomberg. He works in the Multi-Asset Risk System (MARS) Pricing group in London, where he is focused on building scalable and reliable components for portfolio pricing and risk analysis. He is interested in the use of functional programming... Read More →
IZ

Ivy Zhang

Ivy is a Software Engineer at Bloomberg LP where she focuses on development of execution management system.
Monday September 14, 2026 11:00 - 12:00 MDT
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11:00 MDT

From Firmware to Screen: Real-Time Control, Simulation, and Visualization in C++23 With CUDA and Unreal Engine
Monday September 14, 2026 11:00 - 12:00 MDT
What does it take to build a real-time embedded control system in modern C++, simulate its environment, command it from a browser, and watch it fly in 3D — all from the same open source ecosystem? This talk follows that pipeline end-to-end: from a C++23 real-time framework that schedules deterministic control loops across POSIX hosts and bare-metal microcontrollers, to GPU-accelerated simulation with CUDA, to web-based operations and telemetry, to live 3D visualization in Unreal Engine.

Attendees will see how a unified runtime architecture can span embedded control, simulation, diagnostics, operations, and visualization without fragmenting into separate software stacks. The talk explores deterministic scheduling, zero-allocation real-time design, cross-platform deployment, and integrating CUDA compute kernels directly into scheduled control loops without blocking execution. It also covers tooling for validating deterministic real-time behavior, along with techniques for streaming telemetry and sensor data between simulation and visualization layers in real time.

The presentation includes live demonstrations of a quadcopter simulation flying a programmed trajectory with lidar feedback, and a full-fidelity aircraft simulation with closed-loop autopilot, engine dynamics, and atmospheric turbulence — both running through the same real-time framework and rendered live in Unreal Engine. Whether you build flight software, robotics systems, industrial controllers, or simulation infrastructure, this talk presents practical architectural patterns for modern real-time systems in C++ that bridge embedded devices, GPU compute, and interactive visualization.

Presenters
Monday September 14, 2026 11:00 - 12:00 MDT
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11:00 MDT

Same Bits Without Losing MIPS: Reproducible Numerics at Full Hardware Speed
Monday September 14, 2026 11:00 - 12:00 MDT
Floating point has a reputation for betrayal. Change the thread count, vector width, compiler flags, reduction tree, or target architecture, and the low bits can move. Parallel algorithms make this worse: the standard often specifies the operation, but not the numerical expression whose result must be reproduced. This talk asks a provocative question: what if reproducible numerics did not have to be slow?

We will show reproducible, deterministic implementations of reduce and scan that exhibit better error behavior on hostile floating-point workloads and can match or beat conventional standard-library implementations on realistic workloads. The trick is not to freeze the execution schedule. It is to specify the expression being computed, then let the implementation use SIMD, threading, blocking, tiling, and platform-specific strategies to compute that expression efficiently.

The key idea, developed through C++ standardization work such as P4016R0 and P4229R0, is reproducibility by reproducing the computation. Instead of asking the implementation to promise a particular schedule, we give the calculation a named expression. Once that expression is chosen, changing the thread count, vector width, chunking, or blocking strategy does not silently change the answer.

A reproducible scan makes this harder than reduce because it does not expose only one final value. It exposes every prefix. A reproducible final sum is not enough if the intermediate results still drift. We will show how expression and observation contracts make those prefixes reproducible without forcing the computation back into a slow sequential order.

Then we go below the algorithm layer, to the places where bits usually escape: FMA contraction, denormals, floating-point environment choices, math-library approximations, and vectorized transcendental functions. The goal is not to get the same answer by turning off the hardware. We will show reproducible vectorized primitives, including transcendental functions, running at speeds comparable to established vector math libraries while preserving a cross-platform numerical contract.

Finally, we put the whole stack under stress: a heterogeneous numerical pipeline across x86-64, Apple Silicon, and CUDA. The data is deliberately hostile, with high cancellation rates and fragile intermediate states. The aim is not to pass friendly benchmark cases, but to reproduce the specified computation, including the same intermediate failures, not just the same final answer, bit for bit, across CPUs, GPUs, and toolchains.

Presenters
avatar for Andrew Drakeford

Andrew Drakeford

Director, UBS
Andrew Drakeford A Physics PhD who started developing C++ applications in the early 90s at British Telecom labs. For the last two decades, he has worked in finance developing efficient calculation libraries and trading systems in C++. His current focus is on making quant libraries... Read More →
Monday September 14, 2026 11:00 - 12:00 MDT
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11:00 MDT

Queue Discipline: A Deep Dive into Lock-Free SPSC, MPSC, SPMC, and MPMC Queues in Modern C++
Monday September 14, 2026 11:00 - 12:00 MDT
Queues are the backbone of concurrent systems — yet most C++ developers treat them as a black box. Pick the wrong queue topology, misplace an alignas, or use the wrong memory order, and you pay for it in microseconds of latency, invisible cache thrashing, or subtle correctness bugs that only manifest under load. This talk is a rigorous, bottom-up treatment of the four canonical concurrent queue topologies: SPSC, MPSC, SPMC, and MPMC. We start with the hardware reality — how cache coherence protocols turn innocent struct layout into a performance disaster through false sharing — and build upward through the C++ memory model, atomic operations, and queue algorithm design. For each topology, we derive the minimal set of memory ordering guarantees required for correctness, show how to exploit producer/consumer asymmetry to eliminate unnecessary synchronization, and demonstrate how alignas(std::hardware destructive interference size) and deliberate padding can be the difference between 100ns and 10ns throughput. We dissect Dmitry Vyukov's MPMC ring buffer, the intrusive MPSC queue, and Michael-Scott's linked-list queue — not just their interfaces, but the why behind every memory order acquire and every phantom cache line. We then go beyond correctness into the practical engineering tradeoffs: bounded vs unbounded, throughput vs latency, contention vs coordination overhead. Real benchmark data shows how these decisions interact non-obviously — an MPMC queue can outperform MPSC under certain producer counts, and seq cst where you don't need it can quietly halve your throughput. Attendees will leave with a clear mental model for choosing and implementing the right queue for their threading topology, a checklist for false sharing audits, and battle-tested code patterns suitable for low-latency production systems.

Presenters
avatar for Anmol Singhal

Anmol Singhal

Gardening, My garden
Anmol has spent 5 years working as a quantitative developer at Goldman Sachs and IMC trading. Previously he completed his education from NYU and BITS Pilani. Most recently he developed multi threaded applications for trading application and improved software performance. He errs on... Read More →
Monday September 14, 2026 11:00 - 12:00 MDT
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15:15 MDT

Escaping the AST: A Data-Oriented, Lock-Free Parallel Compiler Architecture
Monday September 14, 2026 15:15 - 16:15 MDT
The architecture of legacy compilers presents limitations for modern software development. As codebases scale, developers face increased compilation times. While language complexity is often cited, key architectural bottlenecks include pointer-chasing across deeply nested ASTs (cache misses), single-threaded type resolution, and significant thread-lock contention (RwLock) during parallel semantic analysis. What happens when we discard the Abstract Syntax Tree entirely and apply strict Data-Oriented Design to the compiler itself?

In this session, we will explore the internal architecture of the Vx compiler frontend—a heterogeneous systems programming language to safely maximize utilization of available CPU cores. We will dissect how to translate complex, tree-like program semantics into flat, contiguous arrays of 256-bit bit-packed Global Identifiers (GIDs).

By stepping away from traditional recursive tree-walking and object-oriented compiler design, attendees will learn how to implement high-throughput parallel pipelines.

This talk is not just for language designers. The architectural patterns used to build the Vx compiler—flattening graphs into arrays, deferred identity, and lock-free synchronization boundaries—are directly applicable to any C++ developer building high-performance, multithreaded systems.

Presenters
avatar for Aditya Kumar

Aditya Kumar

Software Engineer, Google
I've been working on LLVM since 2012. I've contributed to modern compiler optimizations like GVNHoist, Hot Cold Splitting, Hexagon specific optimizations, clang static analyzer, libcxx, libstdc++, and graphite framework of gcc.
Monday September 14, 2026 15:15 - 16:15 MDT
_4

15:15 MDT

std::simd Without Compromise: Making SIMD in C++26 and Beyond as Fast as Silicon Allows
Monday September 14, 2026 15:15 - 16:15 MDT
For thirty years, SIMD has been the preserve of experts. Writing the fastest C++ has meant hand-written intrinsics, locking code to one architecture, and parallel implementations maintained across every instruction set you ship to. Auto-vectorization can help, but optimizers may give up in complex scenarios where iteration independence isn't obvious. C++26 changes that by putting SIMD in the hands of every C++ programmer, bringing portable, expressive data parallelism into the standard library.

For the engineers who have spent decades writing intrinsics in telecoms, finance, HPC, and embedded systems, migration to std::simd is only worthwhile if it preserves the performance they have fought to achieve. Every cycle counts when code runs tens of thousands of times per second, for years on end, and a portable abstraction that costs ten percent is not a win. The bar for adoption is therefore high: the abstraction must be measurably cheap, the generated code must match hand-written intrinsics, and the tricks and techniques those engineers rely on must all be expressible in the library, not lost in translation.

This talk takes the practitioner's view, aimed squarely at the engineers who write real intrinsics code today and need to know whether std::simd can replace it. It starts with what modern SIMD hardware actually offers, grounding std::simd in real silicon. It then works through the main features of C++26's std::simd with worked examples drawn from the patterns that recur in production intrinsics code, accessible to programmers new to the library and detailed enough for intrinsics veterans to map against their own kernels with all their accumulated tricks and techniques. A look under the hood at our implementation shows how careful API design and aggressive use of hardware features make the abstraction as cheap as the target architecture allows, and how the library fills the gaps on weaker targets with implementations that an expert library author can write once on behalf of every user. The talk closes with a preview of the C++29 proposals being written now to close the remaining gaps, so that std::simd becomes a clear win even for the most performance-critical code.

Presenters
avatar for Ruslan Arutyunyan

Ruslan Arutyunyan

Ruslan is a Senior Middleware Development Engineer specializing in parallel and threading runtimes. He joined Intel in 2017 and has experience in the autonomous driving domain, where he led the development of two libraries. Currently, Ruslan is the lead developer of oneAPI DPC++ library... Read More →
avatar for Daniel Towner

Daniel Towner

Principal Software Engineer, Intel
Dr Daniel Towner is a Principal Systems Engineer at Intel, where he has spent the last two decades helping telecoms software extract every last cycle from modern hardware. With 25 years in the industry behind him, including 12 years as a GCC port maintainer, he now splits his time... Read More →
Monday September 14, 2026 15:15 - 16:15 MDT
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Tuesday, September 15
 

09:00 MDT

Processor Design and C++ Memory Models
Tuesday September 15, 2026 09:00 - 10:00 MDT
std::atomic and std::memory_order are utterly opaque abstractions. It feels like they were put in place to hide some monstrosity that is too complex for mortals to comprehend, and inevitably when trying to understand the underlying reality, the explanations end with 'the processor does weird things' and 'think about it as if...'.

Well, 'think about it as if' no more. In this talk we'll present the gory and wonderful mechanics of cache coherence protocols, store buffers, cache invalidation queues and the in-processor load-store-queue. We'll explain how modern hardware design makes different cores have different views of memory, and what fences and read-modify-write instructions do exactly - for both x86/64 and ARM/RISC-V (which are sometimes dramatically different).

This is an advanced low-level talk located at the borderline of software development and electrical engineering, discussing topics rarely - if ever - discussed at C++ conference talks.

Presenters
avatar for Ofek Shilon

Ofek Shilon

Senior Developer, Speedata
A Mathematics MA by training, but a 20Y C++ developer, writer and speaker in both the Linux and MS universes. Member of the maintainers team of Compiler-Explorer (==godbolt). Fascinated by compilers, debuggers and pretty much anything low level. Fiercely hated by his cat for no apparent... Read More →
Tuesday September 15, 2026 09:00 - 10:00 MDT
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14:00 MDT

What Are We Synchronizing?
Tuesday September 15, 2026 14:00 - 15:00 MDT
Atomic memory ordering is often taught operationally: Use acquire here, release there, and perhaps add a fence “to be safe.” This approach tends to produce cargo-cult synchronization, where atomic operations are selected mechanically without a clear understanding of what information is actually being propagated between threads. In practice, memory ordering is not about memorizing enum values, but about establishing which facts become visible to which observers, and when.

This talk approaches atomic synchronization from first principles. Beginning with the fundamental ideas of publication, visibility, ownership transfer, and synchronization edges, the talk incrementally develops several concurrent structures drawn from real asynchronous systems. Case studies include outstanding-work reference counting, a multi-producer singly-linked publication structure, a concurrently-mutated doubly-linked intrusive list, and the coordination machinery underlying a concurrent operation with multiple concurrent completion modalities. Each structure is used to derive the synchronization requirements imposed by its invariants, rather than selecting memory orderings mechanically.

Along the way, the talk explores the practical meaning of relaxed operations, acquire/release synchronization, and atomic thread fences. Particular attention is paid to understanding what each actually does, when it is necessary, and when it has become a decorative synchronization cargo cult. The goal is not simply to present lock-free algorithms, but to develop a principled way of reasoning about memory visibility and synchronization in real concurrent systems.

Presenters
avatar for Robert Leahy

Robert Leahy

Robert Leahy is a C++ systems engineer specializing in the design of C++ libraries and high-performance infrastructure. Over the past decade he has built latency-sensitive financial systems, contributed to patented database technology, and developed production software for processing... Read More →
Tuesday September 15, 2026 14:00 - 15:00 MDT
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14:00 MDT

Inside a Small Game Engine: An Architecture Tour in Modern C++
Tuesday September 15, 2026 14:00 - 15:00 MDT
According to VGInsights, about 10% of games released on Steam in 2024 used a custom engine, but those games represent 41% of units sold. Most "how an engine works" talks come from the AAA end of that distribution. This one comes from the other end of that distribution: a teaching-scale engine, where every system has to be small enough to understand from first principles. The problems are the same as in a big engine, but the smaller surface is what makes the architecture legible.

In this talk, we'll walk the spine of the engine in modern C++: allocators and handles in the core, the job system, the graphics abstraction question, the asset pipeline split between pipeline-time and runtime, and scene representation including ECS. We finish on serialization, where C++26 reflection (P2996) offers a path past today's reliance on macros and external code generators.

Presenters
avatar for Elias Farhan

Elias Farhan

Head of Department, SAE Institute Geneva
Elias Farhan is the head of the Games Programming department at SAE Institute Genève, as well as founder of the RGB Games Programming Conference.
Tuesday September 15, 2026 14:00 - 15:00 MDT
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14:00 MDT

Breaking the Speed Limit: Building a High-Throughput Hashing Engine With C++26
Tuesday September 15, 2026 14:00 - 15:00 MDT
Modern storage hardware has evolved at a breakneck pace. PCIe Gen 5 NVMe drives can push data at 10 GB/s, yet standard C++ file abstractions often leave them starving for data. Many developers think they need to abandon portability in favor of unmaintainable, OS-specific kernel bypasses to achieve the throughput necessary to saturate these drives. This session is for developers writing high-throughput, performance-critical applications who want to hit bare-metal speeds without sacrificing clean architecture, cross-platform support, or type safety.

Using a high-throughput cryptographic hashing engine as a concrete case study, this presentation demonstrates how to design a hardware-saturating data pipeline built entirely on the idioms of C++26. We will explore how the mathematical design of an algorithm - specifically BLAKE3's binary Merkle tree structure - can be mapped directly to wide SIMD vector lanes and concurrent CPU cores. We will walk through an execution model that completely bypasses the OS page cache, orchestrates memory without heap allocations on the hot path, and unifies OS kernel quirks in a portable way.

By the end of this presentation, you will learn how to replace rigid thread pools with lock-free, asynchronous execution graphs using Sender/Receiver paradigms (std::execution) and vectorization (std::simd). Crucially, we will focus on the build engineering required to make this work today. We will cover how to use advanced CMake tooling to safely compile multi-architecture vector binaries from a single source of truth, how to prevent LTO cross-contamination, and how to structure your pipeline today to seamlessly absorb upcoming C++ features in a world of trailing vendor toolchains.

Presenters
YS

Yannic Staudt

co-founder, tipi.build
Tuesday September 15, 2026 14:00 - 15:00 MDT
_6

15:15 MDT

Lock-Free Timer Scheduling With C++ Atomics
Tuesday September 15, 2026 15:15 - 16:15 MDT
Applications that present rapidly changing market data to human users face a practical challenge: updates may arrive thousands of times per second, but humans only benefit from periodic refreshes. Efficiently coalescing and scheduling that work without overwhelming CPU resources becomes a concurrency problem rather than simply a rendering problem.

This talk demonstrates how modern C++ atomics can be used to build a lock-free timer scheduler optimized for extremely high update rates. The scheduler follows a single-producer, multiple-consumer design in which work items represent recurring tasks that must execute periodically. Consumers process scheduled work and re-schedule it for future execution without relying on traditional locks or centralized coordination.

The most unusual aspect of the design is its “reverse work stealing” behavior: consumers can proactively give away work to other consumers and become idle themselves. Rather than distributing work evenly across all threads, the scheduler attempts to pack work onto as few cores as possible, reducing idle spinning, lowering CPU utilization, and improving cache locality. Because tasks may have highly variable execution times, the scheduler must also prevent pathological cases where work is endlessly redistributed between consumers.

Attendees will learn how atomics, lock-free forward lists, and memory ordering can be combined to implement high-throughput schedulers with predictable latency characteristics. The talk also discusses practical tradeoffs, implementation challenges, and performance measurements from production-inspired workloads, including producer throughput of approximately 50 million scheduled tasks per second and consumer processing throughput approaching 700 million tasks per second, while keeping migrated work items below 1% in typical workloads.

Presenters
MG

Maxim Gurschi

Maxim Gurschi is a senior software engineer on the FXGO team at Bloomberg, where he is focused on building scalable, high-performance trading systems for electronic foreign exchange trading. In this role, he explores practical applications of modern C++ (20 and above) in latency-sensitive... Read More →
Tuesday September 15, 2026 15:15 - 16:15 MDT
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Wednesday, September 16
 

09:00 MDT

Awaiters and Awaitables
Wednesday September 16, 2026 09:00 - 10:00 MDT
C++20 coroutines come with a reputation for complexity — and writing your own coroutine return type deserves that reputation. But here is the good news: you probably don't have to. With std::generator in C++23, high-quality libraries like Asio and cppcoro today, and std::task on its way in C++26, most developers can simply write co_await and move on.

There is one gap, however. Sooner or later, every developer using coroutines needs to bridge an existing asynchronous interface — a timer, an I/O operation, a thread pool callback, a legacy future — into the coroutine world. That bridge is built with awaiters and awaitables, and that is exactly what this session teaches.

We will start from first principles: what does co await actually do? We will demystify the three functions that form the awaiter protocol — await ready, await suspend, and await resume — and build a clear mental model for each. We will implement a real awaiter from scratch, then explore how symmetric control transfer keeps the call stack flat across deeply chained async operations. Next, we will learn how to make any existing type co await-able without modifying it, using operator co await, and how await transform lets you restrict or adapt awaitable behavior to a specific coroutine context. Finally, we will look at how to write cancellation-aware awaiters using std::stop token, so your coroutines respond promptly when work is no longer needed.

No prior coroutines experience is assumed. If you know what co await looks like on the surface but not what happens underneath it, this session is for you. You will leave with both the knowledge and the code to wrap any asynchronous operation into a first-class co await expression.

Presenters
avatar for Mateusz Pusz

Mateusz Pusz

C++ Trainer | Principal Engineer, Train IT | Epam Systems
A software architect, principal engineer, and security champion with over 20 years of experience designing, writing, and maintaining C++ code for fun and a living. A trainer with over 15 years of C++ teaching experience, a consultant, a conference speaker, and an evangelist. His main... Read More →
Wednesday September 16, 2026 09:00 - 10:00 MDT
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09:00 MDT

CUDA Tile C++: Practical Automatic Parallelization for the GPU
Wednesday September 16, 2026 09:00 - 10:00 MDT
CUDA Tile C++ is a novel C++ DSL and compiler that automatically parallelizes array operations across GPU threads while presenting a single logical thread to the programmer. In CUDA Tile C++, parallelism is expressed through SIMD-style operations on arrays of data called "tiles" while memory accesses are written using structured memory abstractions. The compiler analyzes the tile and memory operations to generate an equivalent multi-threaded program that leverages the advanced hardware capabilities of modern GPUs. This allows the user to write simple programs that exploit GPU parallelism without needing to manage low level hardware concurrency.

As GPU architectures evolve to meet the demands of high performance computing, the traditional multi-threaded GPU programming model becomes increasingly unwieldy. To achieve optimal performance, the GPU programmer must manage a growing variety of hardware features including shared memory, Tensor Memory Accelerators, and Tensor Cores. Traditional CUDA code is deeply coupled to the underlying hardware resulting in complex and non-portable algorithms. The CUDA Tile C++ compiler removes the need for coordinating these low level hardware details, freeing the user to reason about their algorithm rather than asynchronous code.

The tile programming model introduces three key abstractions:

  • cuda::tiles::tile - a multi-dimensional array with value semantics whose operations are parallelized across the GPU
  • cuda::tiles::tensor_span - a view into a multi-dimensional in-memory array with an interface similar to std::mdspan
  • Tile Views - adapters that present a uniform "chunking" of a tensor_span which gives the compiler visibility into memory access patterns
In this talk, we will explore how these abstractions allow NVIDIA's Tile C++ compiler to schedule the program across hardware threads all while preserving the illusion of a single-threaded abstract machine to the user.

Presenters
ES

Ezra Stein

Ezra Stein is a Senior Compiler Engineer working on NVIDIA's CUDA C++ Frontend team. Since joining the company in 2025, Ezra has focused primarily on the design and implementation of CUDA Tile C++. Prior to working at NVIDIA, Ezra spent 5 years developing MATLAB to C++ source-to-source... Read More →
Wednesday September 16, 2026 09:00 - 10:00 MDT
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14:00 MDT

Interesting Upcoming Low-Latency, Networking, Concurrency, and Parallelism Features from Kona 2025, Croydon 2026, and Brno 2026
Wednesday September 16, 2026 14:00 - 15:00 MDT
This talk is the 2026 edition of our series that highlights low-latency, networking, parallelism, and concurrency proposals to the C++ Standards Committee, especially those discussed in the Kona 2025, Croydon 2026, and Brno 2026 meetings. This talk from the Concurrency TS2 Editors, DG and SG14/19 chair will describe the following features and show how they can be used. It will also give their motivation, background, and their place within the overall framework of C++ low latency, networking, parallelism and concurrency:

Atomic Compare and Hazard Pointers Reclamation Control

  • We discuss a proposal for atomic compare operations that clarify programmer intent and simplify static analysis by avoiding the unnecessary leakage of atomic values. We also explore how these operations complement recent proposals to enhance the expressiveness of atomics, such as the use of tagged pointers.
  • We examine techniques for controlling C++26 hazard pointer reclamation, demonstrating how to offload retirement overhead to asynchronous executors to ensure predictable thread latency. We show how this capability can prevent specific deadlock scenarios and assess whether such controllers should be standardized or remain user-space patterns.
Twenty-One Years Without Sockets, The History of Networking in C++ and What We Learned Along the Way

  • Go has standard networking. Rust has standard networking. C++ has been trying since 2005. This talk tells the twenty-one-year story in seventeen minutes: the library that shipped but never standardized, the dependency that blocked it, the coroutine revolution that changed the assumptions, the technical discovery that explains why I/O doesn‚Äôt fit the three-channel model cleanly, and the bridge that lets both models win. Three decision points, three lessons, one live question: how should coroutines and senders coexist for C++29? No villains. Just the story and the engineering. Networking is now finally a C++29 priority, so said the Direction Group‚Äôs P5000.
Out-of-Thin-Air (OOTA) Values.

  • The memory models for high-level languages, including C++, C, Rust, and even Java, have been prone to out-of-thin-air values. For example, given two atomic integers X and Y, both initially zero, if one thread does a relaxed assignment from X to Y and the other does a relaxed assignment from Y to X, the mathematical C++ memory model does not rule out the outcome where both X and Y have the value 42. However, both communication and computation take time, and so we have proven that OOTA values cannot happen on real-world production-quality computer systems. This result makes compiler-writers‚Äô lives easier, and also eases the jobs of those brave individuals pursuing the full mathematical OOTA problem by relieving them of the need to live within CPU and memory constraints of production-quality compilers.
Discussion

There are other features under discussion, but the features we will present seem close to approval, are particularly interesting, and/or are relatively non-controversial. We will show use cases for each and prognosticate their journeys to C++26 and beyond. This will help programmers in concurrency, lock-free programming, and low-latency applications understand how best to take advantage of each of these important facilities.

Presenters
avatar for Paul E. McKenney

Paul E. McKenney

Software Engineer, Facebook
Paul E. McKenney has been coding for almost four decades, more than half of that on parallel hardware, where his work has earned him a reputation among some as a flaming heretic. Paul maintains the RCU implementation within the Linux kernel, where the variety of workloads present... Read More →
avatar for Maged Michael

Maged Michael

Staff Software Engineer, Category Labs
Maged Michael is the inventor of several concurrent algorithms including hazard pointers, lock-free allocation, and multiple concurrent data structure algorithms. His code and algorithms are widely-used in standard libraries and production. His 2002 paper on hazard pointers received... Read More →
avatar for Michael Wong

Michael Wong

CTO, Distinguished Engineer, YetiWare
Michael Wong is the CTO of YetiWare an AI company, and was a Distinguished Engineer/VP of R&D at Codeplay/Intel. He is a current Director and VP of ISOCPP, Chair of the C++ Direction Group, and a 25 year senior member of the C++ Standards Committee with more than 15 years of experience... Read More →
Wednesday September 16, 2026 14:00 - 15:00 MDT
_1

15:15 MDT

Readable Async Workflows in Modern C++: Coroutines Meet std::expected
Wednesday September 16, 2026 15:15 - 16:15 MDT
What makes an async workflow readable? Not just linear control flow — you also need to see where errors go, what each step depends on, and how failures compose. This talk takes a single production workflow — multiple async RPC calls with conditional branching, parallel fan-out, and partial-failure handling — and shows it implemented in three paradigms: callbacks with thread pools, a workflow orchestration graph over futures, and coroutines with std::expected. We evaluate each through four questions: where does the control flow live, the error flow, the coupling, and the migration risk?

Coroutines restore linear control flow, but without structured error composition, the workflow drowns in manual failure checks at every step, that is more error-handling code than business logic. Task
Presenters
FL

Futong Liu

Futong Liu is a software engineer at Bloomberg, where he works on distributed backend systems for financial infrastructure, with a focus on trading systems built in modern C++. He holds a master’s degree in Computer Science from EPFL. His work spans asynchronous programming, service... Read More →
Wednesday September 16, 2026 15:15 - 16:15 MDT
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Thursday, September 17
 

09:00 MDT

Tying up Loose Threads: Making Your Project No-GIL Ready
Thursday September 17, 2026 09:00 - 09:30 MDT
Python's Global Interpreter Lock, which determines which single thread can execute native Python code and call C API functions, simplifies writing multithreaded code. By default, the most popular C++ bindings to this API, pybind11 and Cython, implicitly enables the GIL by default. However, sticking with this execution model leaves out extra performance afforded by modern multicore CPUs with hyperthreading, as automatic locking and unlocking of the GIL does not scale well with thread counts, especially in performance-sensitive workloads.

The newfangled free-threaded interpreter promises salvation when running either pure Python code or with compiled extensions. General multithreading rules apply (prefer thread-local variables, using locks to prevent simultaneous access of shared data), but when dealing with projects containing compiled extensions that directly or indirectly interface with Python's C API, more porting rules also apply.

Key porting tips, including projects using the Limited API, include: port native code away from C API functions that avoid borrowed references because they aren't thread-safe; modify unit tests to catch concurrency bugs arising from assuming the presence of the GIL; and extend CI coverage of Python interpreters both for testing and to build free-threaded compatible wheels.

Presenters
CL

Charlie Lin

Freelancer, N/A
Thursday September 17, 2026 09:00 - 09:30 MDT
_5

09:00 MDT

Back to Basics: Loops in C++
Thursday September 17, 2026 09:00 - 10:00 MDT
A fundamental control structure of each programming language are loops. And we all expect them to be simple and self explanatory. However, C++ would not be C++, if there would be no tricky details to learn and respect about loops in C++.

This talk takes its time to discuss the various ways and approaches to program loops in C++. Beside basic while and for loops, we talk about the range-based for loop, and all the extensions recently added to these control structures.

In addition, we will look at other ways to program loops in C++, such as using algorithms and how to deal with parallel computing in a loop.

As a result you get a deeper understanding of the various ways loops can be programmed in Modern C++ so that you know better how to use them in practice.

Presenters
Thursday September 17, 2026 09:00 - 10:00 MDT
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15:15 MDT

Coroutines for Dummies
Thursday September 17, 2026 15:15 - 16:15 MDT
C++20 coroutines are a game-changer for writing asynchronous code and generators, but they come with a steep learning curve. This talk is designed to simplify the concept and make coroutines more approachable.

We’ll focus on co_await — how it works, what it does under the hood, and why it's useful. If you’ve been curious about coroutines but found the resources confusing, this talk is for you.

Presenters
Thursday September 17, 2026 15:15 - 16:15 MDT
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15:15 MDT

Leveraging LLM to Generate Unittests for Notifiers in Taskflow
Thursday September 17, 2026 15:15 - 16:15 MDT
Notifiers are a critical synchronization primitive in task-parallel programming systems such as Intel TBB and Taskflow, responsible for efficiently sleeping and waking worker threads as tasks become unavailable and available over and over again, directly impacting scheduler throughput and latency. Correctness here is non-negotiable: a single missed wakeup can significantly hamper the performance of an entire program. Yet writing strong unit tests for notifiers is notoriously difficult, because the bugs they target, lost wakeups, spurious wakes, race conditions, are timing-dependent, non-deterministic, and often only surface under specific thread interleavings that are hard to force reliably.

The problem is compounded in practice. Notifier implementations evolve constantly: small algorithmic tweaks, memory ordering changes, and refactors across systems demand a fresh round of carefully constructed tests. This is tedious, expertise-heavy work that takes a lot of time and engineering effort. In this talk, we explore using Large Language Models (LLMs) to automate the generation of the unit tests for notifiers. Specifically, we will demonstrate how LLM-generated tests, guided by proper prompts can systematically stress the two-phase wait protocol across Notifiers in Taskflow. We will show this in a widely used Notifier implemented in Taskflow. We are able to find an undiscovered bug that has been existing in the project.

Presenters
SS

Snikitha Siddavatam

Snikitha Siddavatam is a Computer Science and Data Science student at the University of Wisconsin-Madison, expected to graduate in May 2027, with coursework spanning machine learning, artificial intelligence, distributed systems, data visualization, and advanced algorithms. Snikitha... Read More →
Thursday September 17, 2026 15:15 - 16:15 MDT
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15:15 MDT

The Latency Slippage: Understanding the Hidden Costs of Caching for Low Latency C++
Thursday September 17, 2026 15:15 - 16:15 MDT
Choosing cache-friendly data structures is a well-known optimization, but it's rarely the whole story. This talk goes deeper, exploring the hardware mechanics that dictate real-world performance and showing where significant gains are still left on the table.

We'll start from the ground up: what actually happens inside the cache hierarchy when your code issues a memory read or a software prefetch? Understanding the hardware lets us answer, when you should prefetch manually, and when you should trust the hardware prefetcher.

From there, we'll examine the invisible cost of multi-core C++. Cache coherency protocols (MESI/MOESI) can silently degrade performance through false sharing, RFO stalls, and coherency storms. We'll walk through how to diagnose these issues using hardware performance counters and how to eliminate them.

Additionally, we will contrast these behaviors across the data cache (DCache) and instruction cache (ICache), and analyze how Translation Lookaside Buffers (TLBs) impact overall memory read latency.

Finally, we'll tie it all together by combining hardware insight with application profiling data to arrive at practical strategies for low latency C++, packaged as an application-aware memory allocator.

Presenters
SG

Sanchit Gupta

Sanchit Gupta graduated from Indian Institute of Technology, Madras with Honours in Bachelors of Technology in Computer Science and Engineering. Since graduating, Sanchit has worked for Graviton as a Low latency Software Developer
Thursday September 17, 2026 15:15 - 16:15 MDT
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Friday, September 18
 

10:30 MDT

Senders, Receivers, and Robots: Structured Concurrency for Autonomous Navigation
Friday September 18, 2026 10:30 - 11:30 MDT
To navigate safely, a robot must simultaneously ingest high-frequency sensor data, compute complex spatial algorithms, and publish control commands. Historically, frameworks like ROS 2 have handled this via asynchronous callbacks. However, as autonomous stacks scale, relying heavily on unstructured callbacks can obscure control flow, making state synchronization difficult and robust task cancellation notoriously complex.

This talk explores how to transform unstructured, callback-based architectures in a robotics navigation stack into declarative pipelines using structured concurrency (specifically, C++ Senders and Receivers via stdexec). Attendees will dive into two real-world architectural examples: a collision monitor and a waypoint follower, showcasing readable logic pipelines, thread-hopping between an event loop and a static thread pool, and clean task cancellation.

Presenters
NE

Nahuel Espinosa

Software Engineer, Ekumen
Nahuel Espinosa graduated as an Electronics Engineer from UTN (National Technological University) in Buenos Aires. Since graduation, Nahuel has worked with a variety of systems and technologies: - Robotics applications (e.g., localization algorithms based on particle filters, rigid-body... Read More →
Friday September 18, 2026 10:30 - 11:30 MDT
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13:30 MDT

Implementing Async RAII
Friday September 18, 2026 13:30 - 14:30 MDT
C++ lifetime management is fundamentally built around synchronous scope exit. Constructors establish invariants, destructors release resources, and RAII permits ownership and cleanup to compose naturally with ordinary control flow. Asynchronous systems disrupt this model. Destruction may itself require asynchronous work, and “just launch another task in the destructor” quickly turns deterministic lifetime management into unstructured background activity.

This talk explores the implementation of async lifetime management in std::execution, based on the enter/exit scope sender framework proposed in P3955. Rather than treating async construction and destruction as special cases, the model reframes them as composable asynchronous protocols built around explicit async scope entry and exit operations. The talk follows the process of turning these ideas into working code, beginning from the low-level enter/exit sender abstractions and progressively assembling higher-level lifetime facilities on top. Along the way, the implementation uncovers an important self-similarity in the problem domain: Higher-level async lifetime facilities can themselves be expressed in terms of the same lower-level async lifetime primitives.

The implementation discussion focuses on the machinery required to make these guarantees real: Coordinating async teardown within structured concurrency, managing partially-entered scopes, and preserving deterministic cleanup semantics even when destruction itself becomes asynchronous. The resulting design serves both as a practical exploration of async lifetime management and as a case study in how implementing an abstraction can reveal deeper structural properties hiding inside the model itself.

Presenters
avatar for Robert Leahy

Robert Leahy

Robert Leahy is a C++ systems engineer specializing in the design of C++ libraries and high-performance infrastructure. Over the past decade he has built latency-sensitive financial systems, contributed to patented database technology, and developed production software for processing... Read More →
Friday September 18, 2026 13:30 - 14:30 MDT
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14:45 MDT

Escaping 1996: Meta-Modern C++ Techniques for Embedded Systems
Friday September 18, 2026 14:45 - 15:45 MDT
The software in most embedded projects written in 2026 looks like the software in embedded projects written in 1996. This isn't because 1996 was the peak of innovation and quality but rather has more to do with biases and FUD. Unfortunately, much of the world suffers from these choices: users, developers, managers, and shareholders.

There are better ways to write firmware for embedded systems; proven techniques and implementation strategies that I will describe in this talk. We will explore techniques based on abstraction and composition that maximize understanding while reducing the codegen footprint. We will apply these strategies at all levels of the firmware stack: interrupts, register manipulation, peripheral communications, and the application glue.

Join me and leave with open-source libraries, an open-source starter project, and techniques that you can apply to your greenfield and existing projects.

Presenters
avatar for Michael Caisse

Michael Caisse

Senior Principal Engineer, Intel
Michael started using C++ with embedded systems in 1990. He continues to be passionate about combing his degree in Electrical Engineering with elegant software solutions and is always excited to share his discoveries with others. Michael is a Senior Principal Engineer at Intel where... Read More →
Friday September 18, 2026 14:45 - 15:45 MDT
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