---------- Forwarded message --------- From: "Nathalie Chan King Choy (Windows on Arm)" <woa@hub.corecollective.dev> Date: Thursday, 30 July 2026 at 11:00:25 UTC-7 Subject: Fwd: [CoreCollective WoA] Notes: 2026-07-28 CoreCollective Windows on Arm Technical To: CoreCollective Windows on Arm Hi all, The notes from this week's call are below. Please let us know if you spot any errors or important omissions. Thanks & regards, Nathalie -- CoreCollective Community Manager Android & WoA working groups *Attended:* Anthony Dave W. Evgeny K. Gleb K. John S. Marcus Mayank A. Nathalie CKC Omair J. Paul B. Randy L. Tamas P. Thomas D. Tyler M. *Links shared in chat:* - https://github.com/khmyznikov/PyEnv-WoA-State/issues/50# issue-5000192882 got a first issue from community ☺️ - https://github.com/StrawberryPerl/spbuild/issues/ 20#issuecomment-3206756096 - https://github.com/msys2/msys2-runtime/pull/344 - https://github.com/lazka *AI Notes - please notify us of inaccuracies:* Meeting Overview - Maintainership and collaborative support tracking structures for ecosystem libraries on Windows on Arm. - Path to remove the Python experimental designation. - Toolchain progression, patch submittals, and runtime compatibility blocks across Strawberry Perl, GCC, MSYS2, PyTorch, and TensorFlow. Decisions/Key Takeaways - The Windows Arm Working Group GitHub repository is where we are planning to track community issues and manage library maintainership discussions, rather than a WoA maintainer mailing list. - Technical representatives from Arm, Qualcomm & Microsoft will join the working group GitHub repository to increase visible team. - Priority order: completing the native compiler toolchain and upstreaming Cygwin target changes to binutils ahead of active Strawberry Perl distribution enablement. - [Deferred] Categorizing remaining blocked packages into localized maintainer strategic groups was deferred to an upcoming offline breakout working call due to session time constraints. - TensorFlow will be delivered as a localized snapshot release through a partner repository. Action ItemsDave W. - Discuss internally at Arm to identify technical resources who will join the working group repository as external collaborators & send their GitHub IDs to Nathalie. - Confirm with Chris if ACL functions are actively being folded directly into an alternative library & let Marcus know. Evgeny K. - Arm to submit the dynamic link library relocation patch to unblock upstream native toolchain compilation by end of day today. - Contact Johannes directly & try to understand reason for review delays surrounding the MSYS2 CI pull request from Qualcomm. Gleb K. - Present the Windows Arm Working Group GitHub repository option to the PyArrow mailing list for community discussion Marcus - Engage Steve Dower by the end of this week to confirm ecosystem package requirements and baseline milestones for removing the Python experimental tag, check if we have priority inversions (dependencies on non-top-1000 packages), and pointers to community members who could represent verticals for testing - Contact Tucker Burns about PyTorch CI status and resourcing limits for making Windows on Arm wheels from nightlies, investigating issues, etc. Mayank A. - Gather and forward Qualcomm engineer GitHub accounts to Nathalie CKC to add as external collaborators to WoA Technical WG GitHub repo - Contact Christoph Reiter (Lazka) directly to secure review engagement on the pending MSYS2 runtime pull request Nathalie CKC - Issue external collaborator invitations to repository joiners upon receipt of developer GitHub identifiers (see chat for Marcus') - Coordinate and schedule an offline breakout call with Mayank A., Gleb K., and Anthony to bucketize remaining blocked packages. Omair J. - Present list of critical Python packages situated outside the top 1,000 ranking during the next group assembly. Paul B. - Investigate internal channels at Arm to determine why official ACL wheel distributions for Windows Arm64 stopped after August 2025. For Future - Complete the upstreaming of Cygwin target modifications to binutils during the current calendar year before the submission window closes at the end of November. - Allocate technical resources later this year to establish a benchmarking workflow and perform detailed GCC performance evaluation against LLVM and MSVC. Connect Evgeny's team with the Microsoft engineers who have been running spec tests. NotesPyArrow & GitHub Working Group Support Structure - Upstream project maintainers require dedicated, interactive support to troubleshoot Windows on Arm test regressions and prevent them from blocking primary framework releases. Upstream maintainers explicitly declined physical hardware donations due to corporate funding limitations governing external project labor. - Relying on an individual named maintainer poses a continuity risk because current project funding is only secured through later this year. Implementing a shared team-based responsibility model via a joint repository reduces the project bus factor. - The repository currently lists only two active contributors, prompting a push for expanded technical representation from Microsoft, Arm, and Qualcomm engineers. Python Experimental Status & Package coverage - Steve Dower retains gatekeeping authority over Windows Python binaries, applying subjective validation metrics centered on overall community sentiment and successful basic script execution during the opening 10 minutes of operation. - Compatibility tracking indicates that 95% of the top 1,000 most downloaded packages run successfully on native targets. The group's primary objective is to prevent workflow breaks when native execution becomes the platform default. Need to get some testing done on verticals. - Relying solely on download lists risks missing low-level dependencies or rapid-iteration frameworks in emerging sectors like AI that lack high download volume. - Extracting architecture-specific package download metrics is highly limited because command-line tools and user agents systematically mask or omit native Windows on Arm silicon descriptors. Toolchain and Strawberry Perl Blockers - Strawberry Perl acts as the primary default Perl implementation on Windows, causing widespread build blockages because package managers like Conan structurally reject mixed-architecture pipelines even though emulated x64 Perl executes cleanly for build utilities like OpenSSL. - A Microsoft partner currently implements an emulated execution strategy for internal workloads, incurring significant resource overhead from double-jitting operations that translate X86 instructions while compiling Perl scripts to machine blocks. - Compiling the basic runtime environment is achievable through standard cross-compilation frameworks, whereas generating the full package distribution requires a completely integrated native toolchain. - A severe P1 compiler regression affecting MinGW target builds across both X64 and Arm64 architectures was successfully isolated, resolved, and integrated upstream. MSYS2 and Git for Windows Status - Internal validation confirms that the MSYS2 runtime and core Git for Windows systems function correctly, but upstream integration remains stalled due to a lack of review engagement on an X64 CI pull request. - Qualcomm's internal tracking shows 289 executed validation tests with only 3 or 4 failures stemming from POSIX spawn updates and underlying GCC behaviors. Machine Learning Runtimes (PyTorch, ACL, TensorFlow) - PyTorch optimization continues via nightly builds; standard release wheel deployments are delayed because engineering resources are unavailable to troubleshoot downstream production pipeline failures. - Official ACL wheel updates for Windows Arm64 have been fully halted since August 2025 due to baseline MSVC integration limitations created by internal inline assembly blocks. - TensorFlow compilation has been achieved internally, successfully resolving 500 to 600 validation passes out of approximately 3,000 test cases; current frictional boundaries are limited to Google dependencies like gRPC IO.