C# now beats Rust on WASM size 🔗 https://github.com/zion-sati/NetWasm 📝 NetWasm is an independent compiler, runtime and SDK that compiles C# and .NET CIL directly to WebAssembly, without the desktop CLR, Mono or dotnet.js. For a print-42 workload with its precise Compact GC, the standalone WASI Preview 2 component is 47,895 bytes, 10.7% smaller than Rust’s equivalent 53,635-byte build and about 319 times smaller than a Blazor WebAssembly .NET 11 RC1 app. Benchmarks on Wasmtime show it running 26 to 40% faster than Mono AOT on allocation and GC workloads. Version 0.10.0 rebuilds its garbage collectors, removing the Boehm collector and speeding up allocation-heavy programs. 📰 Hacker News · 🏷 c, .net, c#, compiler · ⬆️ 19 · 💬 1 · ⏱ 10 min

From KTIR to SpyreCode: An MLIR Dataflow Backend for IBM Spyre 🔗 https://pytorch.org/blog/from-ktir-to-spyrecode-an-mlir-dataflow-backend-for-ibm-spyre 📝 PyTorch describes the backend compiler that turns Inductor’s scheduling decisions into code for the Spyre accelerator. KTIR, an MLIR dialect, records Inductor’s work division and scratchpad placement across Spyre’s 32 cores, each with 2 MB of scratchpad. The open-source Dataflow Scheduler lowers KTIR through ScheduleIR into DataflowIR, building a dataflow pipeline guided by an architecture description rather than hard-coded chip logic. Device-specific stages then turn DataflowIR into SpyreCode, a symbolic binary plus a job plan the runtime prepares once and launches repeatedly. Version 1 handles elementwise ops with broadcast and reduction dimensions, with the first op coming up about 4x faster and later ops about 8x faster than the previous stack, with matrix multiplication support coming next. 📰 PyTorch · 🏷 pytorch, compiler · ⬆️ 0 · 💬 0 · ⏱ 28 min

TypeScript 7.0 Migration Guide: Performance, Compatibility, and Upgrade Steps 🔗 https://www.syncfusion.com/blogs/post/typescript-7-upgrade-guide 📝 TypeScript 7.0 introduces a native compiler rewritten in Go, with Microsoft’s benchmarks showing 7.7x to 11.9x faster full builds across five open-source projects (VS Code, Sentry, Bluesky, Playwright, tldraw). The guide walks through what changes with the new compiler, including the removal of the programmatic compiler API, a new LSP-based language server, and tsconfig.json default changes carried over from TypeScript 6.0. It covers checking compiler API and tooling dependencies via grep/npm commands, verifying framework compatibility (Vue, Astro, Svelte, MDX, Angular templates may still need TypeScript 6.0), benchmarking clean builds, incremental rebuilds, and up-to-date builds in your own repo, tuning experimental concurrency flags (–checkers, –builders, –singleThreaded), and running TypeScript 6.0 and 7.0 side by side using the @typescript/typescript6 compatibility package. A migration checklist and FAQ section round out the guide, with the overall recommendation to benchmark your own codebase before upgrading rather than relying on Microsoft’s published numbers. 📰 Syncfusion · 🏷 build-systems, compiler, typescript · ⬆️ 0 · 💬 0 · ⏱ 15 min

A new way to think about borrow checking (in reverse) 🔗 https://verdagon.dev/blog/reverse-borrow-checking 📝 Evan Ovadia describes a novel borrow checker design in his Valen programming language that scans functions backwards, from the last statement to the first, to detect use-after-free errors. The post walks through Valen’s four-phase compilation pipeline, explains how static grouping tracks where references point, and shows worked examples of the backward DECLARE/USE/MUTATE scan catching a use-after-free bug and validating a correct program. It also covers how loops are handled with additional LOOP START, revived_after_this, and mutations_after_this bookkeeping, and argues the reverse approach is more convenient, loop-friendly, and faster than a forward scan. The piece closes with future plans for closures, control-flow graphs, and comparisons to Rust’s lifetime inference. 📰 Hacker News · 🏷 rust, compiler · ⬆️ 3 · 💬 0 · ⏱ 14 min

Gleam case exhaustiveness, as a fan 🔗 https://oyster.pckt.blog/gleam-case-exhaustiveness-as-a-fan-fd4whyp 📝 A deep dive into how Gleam’s compiler (specifically exhaustiveness.rs) determines whether a case expression covers every possible value and reports exactly which pattern is missing. The piece traces the theoretical lineage from Lennart Augustsson’s 1985 pattern-matching compilation paper through Luc Maranget’s 2007 and 2008 papers on warnings and decision tree construction, then explores Gleam-specific innovations not covered in the literature: handling string prefix patterns combined with guards, exhaustiveness logic for bit arrays (including BEAM/JS unification edge cases), type-narrowing after pattern matching, and generating user-friendly error messages that respect a program’s actual import aliases. 📰 Lobsters · 🏷 functional-programming, compiler, gleam · ⬆️ 0 · 💬 0 · ⏱ 15 min