Hayden Barnes

Hello! I am Hayden Barnes. I am an open source partner manager, community builder, developer relations professional, and experienced engineering manager. Currently Senior Open Source Partner Manager at HeroDevs, where I lead Never-Ending Support (NES) for .NET and do other interesting thing.

I am a six-time Microsoft MVP (2020–2025) with a focus on Windows Subsystem for Linux (WSL) and cross-platform/cross-architecture development, and an Arm Ambassador.

Previously:

• Founded Whitewater Foundry - created Pengwin, the first bespoke Linux distro optimized for WSL, featured in the Windows Terminal demo at Microsoft Build 2019 and covered by ZDNet and The Register
• Developer Advocate and Engineering Manager for Ubuntu on WSL at Canonical - grew Ubuntu on WSL from 40k to 100k weekly installs
• Senior Engineering Manager at Rancher Labs (now SUSE) - Windows containers on RKE2, documentation, DevOps, IBM Z coordination
• Community Lead for open source AI/ML at Determined AI / HPE - organized ML-at-Scale community conferences and a hackathon with 800+ registrants
• A lawyer (yes, really - JD from the University of Baltimore, and still admitted to practice)

I am passionate about:

• Sustainable open source
• Cross-platform/cross-architecture development
• Windows Subsystem for Linux
• Old UNIX

I also:

• Blog about WSL, .NET, Linux, and cross-platform development
• Write about .NET security, CVE research, and open source sustainability at HeroDevs
• Write books - author of Pro Windows Subsystem for Linux (Apress)
• Speak at conferences
• Founded and organized WSLConf - the first community conference dedicated to WSL
• Previously co-hosted the Linux Downtime podcast
• Appear on podcasts and streams about Linux, open source, and .NET
• Lead the WSL Community Telegram
• Contribute to open source projects across the ecosystem

HeroDevs

At HeroDevs, I lead .NET Never-Ending Support (NES), providing long-term security patches for end-of-life .NET versions.

Awesome Lists

| Repository | Description | Stars | |---|---|---| | awesome-wsl | Awesome list dedicated to Windows Subsystem for Linux | | | awesome-unix | All the UNIX and UNIX-Like: Linux, BSD, macOS, Illumos, 9front, and more | |

.NET Projects

| Repository | Description | Stars | |---|---|---| | ghcopilot-taskbar-gui | WinUI 3 system tray app for GitHub Copilot with automatic context awareness | | | CVE-2025-55315-repro | Tool that reproduces CVE-2025-55315 in ASP.NET Core (Kestrel) | | | secure-case-notes | HIPAA-compliant mental health case notes with local AI (Sherpa-ONNX + Phi-3) | | | bulkhead | Enterprise policy-aware container execution for .NET | | | cleanup-mastodon | .NET terminal app to bulk-delete Mastodon posts before a date | | | gnomeazureopenaichat | Azure OpenAI chat application with GTK/.NET | |

WSL

I founded Whitewater Foundry and created Pengwin, the first custom Linux distribution built for WSL. Pengwin was featured in the Windows Terminal demo at Microsoft Build 2019. I later organized WSLConf, the first community conference dedicated to WSL. I also maintain the WSL Community Telegram.

I am a Contributor to microsoft/WSL, with the first community pull request merged into the project and engaged on 245+ issues.

| Repository | Description | Stars | |---|---|---| | Pengwin | The first bespoke Linux distribution optimized for WSL (founder) | | | Fedora Remix for WSL | Fedora-based distribution for WSL (founder) | | | Pengwin Enterprise | Enterprise WSL distribution with RHEL/CentOS/Scientific Linux (founder) | | | wslinternals | A collection of nifty WSL-related utilities | |

Arm

As an Arm Ambassador, I contribute to the Windows on Arm ecosystem with 15+ Arm-related PRs across projects including:

• Maintaining a fork of the GitHub Actions Runner with Windows Container support on both x64 and Arm
• Helping port Scoop, the Windows package manager, to Arm
• Arm build support for Pengwin and wslu RPM packages
• Docs and build clarifications for microsoft/onnxruntime-genai on Windows Arm
• Tracking Arm app readiness via is-windows-on-arm-ready

More!

• Automating submission of GPTScript to WinGet and Scoop
• Contributing to CVE research and remediation for end-of-life .NET at HeroDevs — including reporting on CVE-2025-55315 (CVSS 9.9)
• Writing about .NET security, the .NET Foundation, and open source sustainability at HeroDevs
• Blogging about WSL internals, cross-platform .NET, and open source sustainability at boxofcables.dev
• Curating microsoft-opensource — a collection of Microsoft's open source project landscape

Selected Writing

• Pro Windows Subsystem for Linux (Apress) - Author
• HeroDevs Joins the .NET Foundation to Secure and Grow the Open Source Ecosystem
• HeroDevs Joins .NET Security Group: Securing the Future of the .NET Ecosystem
• Critical ASP.NET Vulnerability CVE-2025-55315 Reported: Upgrade Now
• A Practical Decision-Maker's Guide to Responding to CVE-2025-55315
• FAQ About CVE-2025-55315: The 9.9 Rated CVE in ASP.NET Core

Conferences

• Microsoft Build (2019, 2021–2026)
• WSLConf (Founder & Organizer)
• Microsoft Ignite
• KubeCon NA
• Supercomputing
• MLSys
• ICML
• NeurIPS

In the News

| Publication | Article | |---|---| | The Register | WLinux brings a custom Windows Subsystem for Linux experience to the Microsoft Store (Sep 2018) | | The Register | What do WLinux and Benedict Cumberbatch have in common? They're both fond of Pengwin (Mar 2019) | | ZDNet | Pengwin: A Linux specifically for Windows Subsystem for Linux | | ZDNet | Microsoft hosts first Windows Subsystem for Linux conference | | ZDNet | Canonical co-sponsors Windows Subsystem for Linux conference | | OMG! Ubuntu | Canonical Sponsors WSLConf, Microsoft's First Linux Conference (Dec 2019) | | The Register | El Reg gets some unexpected lessons from WSLConf (Mar 2020) | | The Register | Even 2020 cannot bring forth the Year of Linux on the Desktop — "'open source has won', says Microsoft MVP" (Oct 2020) | | OMG! Ubuntu | Linux Kernel 5.4 is Rolling Out Via Windows Update (Feb 2021) | | The Register | Microsoft delays controversial ban on paid-for open source, WebKit in app store — quoted extensively on Microsoft Store open source policy (Jul 2022) | | TechCrunch | Dissecting Microsoft's proposed policy to ban commercial open source apps — quoted by name, tweets embedded (Jul 2022) | | TechCrunch | Microsoft U-turns on policy that would've banned commercial open source apps (Jul 2022) | | The Register | Microsoft tweaks Store policy for open source once again — tweet cited as community outcry (Jul 2022) | | Andrewlock.net | Companies complaining .NET moves too fast should just pay for post-EOL support — extensively features Hayden Barnes and HeroDevs NES for .NET (2025) |

Podcasts & Media

| Show | Episode | Topic | |---|---|---| | Hanselminutes | #994, Apr 2025 | Neverending support for open source | | The Modern .NET Show | S08E07 | .NET NES & a new approach to open source maintenance | | The Modern .NET Show | S08E07B | CVE-2025-33515 & .NET security | | Everyday Heroes | S1E2, Jan 2025 | The Butterfly Effect: from law to Linux legend | | Linux Downtime | Co-host | Linux, open source, and the industry | | LINUX Unplugged | #345, Mar 2020 | Behind the scenes of WSLConf | | LINUX Unplugged | #332, Dec 2019 | The WSL Secrets | | LINUX Unplugged | #268, Sep 2018 | 268: Elementary, My Dear Plasma | | Destination Linux | #158 | Ubuntu on WSL at Canonical | | Level1Techs | Interview | Windows Subsystem for Linux deep dive | | Coder Radio | #353 | A Week with WSL | | The Mike Dominick Show | Episode 19 | Ubuntu WSL | | Landing In Tech | #7 | From lawyer to engineering manager at Canonical | | The Weekly Squeak | Polly Pengwin Pod | Pengwin and WSL | | Coffee & Open Source | Sep 2020 | WSL, Pengwin, and open source community |