Browser-first release with IIFE bundle, CDN distribution, Web Worker support, and framework examples. 419 tests (171 Rust + 248 TypeScript).

• IIFE build — self-contained modern-xlsx.min.js (~29 KB) exposing window.ModernXlsx
• CDN distribution — available on jsDelivr and unpkg, no bundler required
• detectWasmUrl() — auto-detection of WASM binary URL from document.currentScript.src
• initWasmSync(module) — synchronous WASM initialization from pre-loaded buffer
• ensureReady() — lazy auto-initialization on first use (cached Promise pattern)
• Source maps — .map files generated for all build outputs (ESM, IIFE, Worker)

• createXlsxWorker() — off-thread XLSX read/write via Web Worker message passing
• modern-xlsx.worker.js — dedicated worker script with auto WASM init
• Transferable buffers — zero-copy transfer of Uint8Array results back to main thread

• tsdown 3-build config — ESM (primary), IIFE (browser), Worker (off-thread)
• Package exports — "." (ESM), "./browser" (IIFE), "./worker" (Worker script)
• browser / unpkg / jsdelivr fields in package.json for CDN auto-resolution

• Interactive browser playground at docs/site/playground.html
• 6 built-in examples: Hello World, Styled Workbook, Read & Inspect, Batch Data, JSON to Sheet, Formulas & Dates
• Live WASM status indicator, Ctrl+Enter execution, download integration

• React — hooks-based integration with useEffect WASM init
• Vue 3 — Composition API with onMounted WASM init
• Svelte 5 — $effect rune-based WASM init
• Angular — service-based WASM init with standalone components

• Cloudflare Workers — XLSX generation at the edge
• Deno Deploy — server-side XLSX with Deno-native imports
• Service Worker — offline XLSX generation with custom WASM URL

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Complete 0.1.x hardening series. 419 tests (171 Rust + 248 TypeScript).

• Style roundtrip: gradient fills, diagonal borders, DXF styles, cell named styles
• Formula metadata: array formulas, shared formulas, formulaRef, sharedIndex
• Feature roundtrip: hyperlinks, comments, data validation, conditional formatting, sheet protection, page setup
• Edge cases: empty workbooks, malformed XML, boundary values
• Error handling: corrupted files, invalid inputs, graceful degradation
• Streaming & benchmarks: 100K row read/write, parallel parsing, buffer scaling
• Utilities: cell refs, dates, format codes, CSV/HTML/JSON conversion

• push_entity() — zero-allocation XML entity resolution
• Vec::with_capacity() on all XML parse buffers (11 sites)
• from_utf8().unwrap_or_default() replaces from_utf8_lossy() (6 sites)
• entries.remove() in StreamingReader — moves data instead of cloning
• drain() in collect_preserved() — moves preserved entries
• #[non_exhaustive] on error enum

• Module-scoped CELL_REF_RE regex (hoisted from hot loop)
• isolatedDeclarations: true in tsconfig
• Shared WASM init via __tests__/setup.ts

• Migration guide: SheetJS
• Migration guide: ExcelJS
• Usage examples cookbook
• Release roadmap

• GitHub Actions pinned to stable versions
• Rust toolchain: @stable
• Node.js engine: >=24.0.0

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First public release.

• Full XLSX read/write with Rust WASM core
• Cell styling — fonts, fills, borders, alignment, number formats via StyleBuilder
• Data validation — list, number, date, text length, custom formula
• Conditional formatting — color scales, data bars, icon sets, formula-based rules
• Frozen panes, hyperlinks, comments, sheet protection, page setup
• Rich text with RichTextBuilder
• Named ranges, document properties, workbook views, calc chain
• Streaming reader/writer for large files
• Parallel sheet parsing (rayon)
• Cell reference utilities, date utilities, format utilities
• Sheet conversion utilities (JSON, CSV, HTML, array-of-arrays)
• Browser Blob download support
• 342 tests (170 Rust + 172 TypeScript)

Operation	modern-xlsx	SheetJS CE	Factor
Read 100K	1,155 ms	4,927 ms	4.3x faster
Write 100K	5,048 ms	5,048 ms	1.0x
sheetToJson 10K	54 ms	103 ms	1.9x faster

• IIFE browser bundle — modern-xlsx.min.js (29 KB, gzip 10 KB) exposes window.ModernXlsx
• CDN distribution — auto-served via jsDelivr and unpkg
• Browser WASM loader — detectWasmUrl() auto-detects from document.currentScript.src
• initWasmSync(module) — synchronous init from pre-loaded WebAssembly.Module or bytes
• ensureReady() — lazy auto-init wrapper, no-op if already initialized
• createXlsxWorker() — Promise-based Web Worker API for off-thread operations
• Worker entry point — modern-xlsx.worker.js with auto WASM init
• Interactive playground — live code editor at docs site
• Framework examples — React (hook + component), Vue 3 (composable + SFC), Svelte 5 (rune + component), Angular (service + component)
• Edge runtime examples — Cloudflare Workers, Deno Deploy, Service Worker

• tsdown array config: 3 parallel builds (ESM + IIFE + Worker)
• deps.neverBundle replaces deprecated external option
• Source maps for all build outputs
• WASM binary copied to dist/modern-xlsx.wasm for CDN serving

Output	Size	Gzip
ESM module	55 KB	16 KB
IIFE bundle	29 KB	10 KB
Web Worker	6 KB	3 KB
WASM binary	939 KB	—

• 419 total (171 Rust + 248 TypeScript)