perf(binding): box once-per-build futures before spawn_future#9864
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## What `Env::spawn_future` is generic over the concrete future type `F`, and its body instantiates the full tokio task harness (`poll_future`, `Core<T, S>`, `new_task`, scheduler dispatch). Every distinct async body at a `#[napi]` async entry point therefore re-monomorphizes that whole machinery. This wraps the four `BindingBundler` entry futures (`generate`/`write`/`scan`/`close`, 7 call sites) in `Pin<Box<dyn Future + Send>>` via a small `spawn_boxed_future` helper, so napi's `execute_tokio_future` is monomorphized **once per output type** (3 instead of 7) rather than once per future body. ## Why it's safe here These entry points run **once per build** — the future bodies *are* the multi-second bundling pipeline — so the single added heap allocation is unmeasurable. This is deliberately **not** applied to per-module / per-hook futures (e.g. plugin hooks), where the extra allocation would land on a hot path. No behavior change. Part of a broader effort to shrink the native `.node` (binary-size analysis). Exact byte delta will show in the release build; estimated ~30–80 KiB of collapsed task-harness/scheduler code.
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## [1.1.3] - 2026-06-24 ### 🐛 Bug Fixes - `defer_drop` crashes the browser main thread (#9942) by @shulaoda - camel-case: correct camel case for nested values (#9933) by @kb019 - cli: display --help options in camelCase (#9941) by @IWANABETHATGUY - preserve used re-exports under preserveModules (#9122) (#9934) by @IWANABETHATGUY - watch: make close reentrant in event callbacks (#9904) by @hyf0 - git for windows treats symlink files as regular files (#9915) by @AliceLanniste - dev: cancel pending full reload on build error (#9903) by @h-a-n-a - chunking: pass plugin meta to codeSplitting groups name function (#9267) by @Kyujenius - dev: serve assets emitted during HMR/lazy compile (vite#22596) (#9815) by @h-a-n-a - release: dry-run step no longer publishes binding packages (#9866) by @Boshen ### 🚜 Refactor - rolldown_common: model ModuleId as a classified Path/Virtual/Bare enum (#9927) by @Boshen - remove unused LegacyModuleIdx (#9872) by @shulaoda - remove unused StmtInfos::get_namespace_stmt_info (#9870) by @shulaoda - remove unused Module::as_external_mut (#9871) by @shulaoda - remove unused EcmaAst::is_body_empty (#9869) by @shulaoda - drop dead is_css_module handling in resolve_dependencies (#9867) by @shulaoda - drop redundant with_commonjs on cjs source type (#9868) by @shulaoda ### 📚 Documentation - clarify on drafting PRs (#9952) by @h-a-n-a - update contribution guidelines (#9944) by @fubhy - note Rust crates don't follow semver in AGENTS.md (#9905) by @IWANABETHATGUY - add feedback form (#9159) by @TheAlexLichter ### ⚡ Performance - utils: avoid allocation in default_sanitize_file_name for clean names (#9928) by @Boshen - binding: box once-per-build futures before spawn_future (#9864) by @Boshen - utils: avoid wasted allocation in legitimize_identifier_name (#9926) by @Boshen - rolldown: fuse the canonical-name dedup and insert in the renamer (#9900) by @Boshen - rolldown: probe the name map once in ConflictResolver::resolve (#9899) by @Boshen - cut two heap allocations from wrapped ESM init finalize (#9901) by @Boshen - rolldown_plugin_vite_reporter: hoist invariant out_dir prefix out of reporter loop (#9873) by @shulaoda - drop throwaway Vec in wrapped esm init stmt (#9878) by @shulaoda - borrow owner_filename in build-import-analysis AddDeps (#9874) by @shulaoda ### 🧪 Testing - cover preserveModules named export via namespace re-export (#6010) (#9937) by @IWANABETHATGUY ### ⚙️ Miscellaneous Tasks - deps: update napi to v3.9.4 (#9954) by @shulaoda - reduce noise from CODEOWNERS for trival changes (#9953) by @h-a-n-a - deps: update mimalloc-safe to 0.1.64 (#9950) by @shulaoda - deps: update rollup submodule for tests to v4.62.2 (#9931) by @rolldown-guard[bot] - deps: test mimalloc-safe upstream-mimalloc switch in CI (#9930) by @shulaoda - rolldown_plugin_vite_build_import_analysis: remove unused v2 code path (#9917) by @shulaoda - rolldown_plugin_vite_manifest: remove unused is_enable_v2 code path (#9916) by @shulaoda - rolldown_plugin_vite_asset_import_meta_url: remove unexposed native vite plugin (#9896) by @shulaoda - rolldown_plugin_vite_asset: remove unexposed native vite plugin (#9895) by @shulaoda - rolldown_plugin_vite_css_post: remove unexposed native vite plugin (#9894) by @shulaoda - rolldown_plugin_vite_css: remove unexposed native vite plugin (#9893) by @shulaoda - rolldown_plugin_vite_html_inline_proxy: remove unexposed native vite plugin (#9892) by @shulaoda - rolldown_plugin_vite_html: remove unexposed native vite plugin (#9891) by @shulaoda - deps: update github actions (#9909) by @renovate[bot] - deps: update rust crate oxc_sourcemap to v8.0.2 (#9910) by @renovate[bot] - deps: update npm packages (#9912) by @renovate[bot] - deps: update github actions to v7 (#9913) by @renovate[bot] - deps: update rolldown-plugin-dts to ^0.26.0 (#9897) by @renovate[bot] - remove rolldown_filter_analyzer crate (#9865) by @Boshen ### ❤️ New Contributors * @fubhy made their first contribution in [#9944](#9944) Co-authored-by: shulaoda <165626830+shulaoda@users.noreply.github.com>
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What
Env::spawn_futureis generic over the concrete future typeF, and its body instantiates the full tokio task harness (poll_future,Core<T, S>,new_task, scheduler dispatch). Every distinct async body at a#[napi]async entry point therefore re-monomorphizes that whole machinery.This wraps the four
BindingBundlerentry futures (generate/write/scan/close, 7 call sites) inPin<Box<dyn Future + Send>>via a smallspawn_boxed_futurehelper, so napi'sexecute_tokio_futureis monomorphized once per output type (3 instead of 7) rather than once per future body.Why it's safe here
These entry points run once per build — the future bodies are the multi-second bundling pipeline — so the single added heap allocation is unmeasurable. This is deliberately not applied to per-module / per-hook futures (e.g. plugin hooks), where the extra allocation would land on a hot path.
No behavior change. Part of a broader effort to shrink the native
.node(binary-size analysis). Exact byte delta will show in the release build; estimated ~30–80 KiB of collapsed task-harness/scheduler code.