Who contributed to .NET on May 25, 2026?

3 developers shipped this update, including jakobbotsch, KirillOsenkov, and davidwengier.

What were the notable .NET updates?

JIT: Avoid TLS access when restoring async contexts, [cDAC] Restore Frame-walk fallback in Thread.GetContext (#128518), and Update public-signing.md with NGEN details.

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The Wire · Showcase

RUNTIME OPTIMIZES ASYNC CONTEXT RESTORATION, ROSLYN ADDS FULL SEMANTIC TOKEN SUPPORT

By RepoJournal · Filed 06:03 UTC on May 25, 2026 · About .NET

3 people shipped this

davidwengier @davidwengier 2 cited

jakobbotsch @jakobbotsch 1 cited

KirillOsenkov @KirillOsenkov 1 cited

The runtime is eliminating expensive TLS lookups in async context restoration while Roslyn extends LSP compatibility across the board.

The runtime team shipped a significant optimization that avoids TLS access when restoring async contexts in synchronous cases by caching the Thread object at capture time [1]. This change trades a minor NativeAOT size regression for the foundation to optimize Thread accesses downstream, a worthwhile bet on future performance gains. In parallel, the team restored a critical Frame-walk fallback in Thread.GetContext that was accidentally removed, ensuring backward compatibility for data targets that don't implement GetThreadContext [2]. Roslyn shipped full semantic tokens support to Razor, eliminating the artificial constraint that forced LSP clients into range-only mode [4]. This is a low-cost compatibility win that broadens tool support. Documentation got tightened around NGEN behavior for delay-signed and public-signed assemblies [3], clarifying a historically muddy corner of the signing pipeline. The Roslyn team also cleaned up unused initialization helpers and unnecessary usings across the Razor workspace [5], reducing surface area and cognitive load.

Action items

→ Review Thread.GetContext fallback behavior if you're running custom data targets dotnet/runtime [plan]
→ Update LSP client compatibility checks - full semantic tokens now available in Razor dotnet/roslyn [monitor]
→ Test async context restoration performance in your production workloads after consuming the optimization dotnet/runtime [plan]

References

[1] JIT: Avoid TLS access when restoring async contexts ↗ dotnet/runtime
[2] [cDAC] Restore Frame-walk fallback in Thread.GetContext (#128518) dotnet/runtime
[3] Update public-signing.md with NGEN details ↗ dotnet/runtime
[4] Add full semantic tokens support to Razor ↗ dotnet/roslyn
[5] Minor cleanups in Razor Workspaces ↗ dotnet/roslyn

Quick answers

What shipped in .NET on May 25, 2026?: The runtime is eliminating expensive TLS lookups in async context restoration while Roslyn extends LSP compatibility across the board. In total, 20 commits and 6 pull requests landed.
Who contributed to .NET on May 25, 2026?: 3 developers shipped this update, including jakobbotsch, KirillOsenkov, and davidwengier.
What were the notable .NET updates?: JIT: Avoid TLS access when restoring async contexts, [cDAC] Restore Frame-walk fallback in Thread.GetContext (#128518), and Update public-signing.md with NGEN details.

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