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ALWAYS use when writing code importing "@takumi-rs/core". Consult for debugging, best practices, or modifying @takumi-rs/core, takumi-rs/core, takumi-rs core, takumi rs core, takumi.

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kane50613/takumi @takumi-rs/core

Version: 1.0.0-beta.3 Deps: @takumi-rs/helpers@0.73.1 Tags: latest: 0.73.1, beta: 1.0.0-beta.3

References: package.json — exports, entry points • README — setup, basic usage • Docs — API reference, guides • GitHub Issues — bugs, workarounds, edge cases • GitHub Discussions — Q&A, patterns, recipes • Releases — changelog, breaking changes, new APIs

Search

Use skilld search instead of grepping .skilld/ directories — hybrid semantic + keyword search across all indexed docs, issues, and releases. If skilld is unavailable, use npx -y skilld search.

skilld search "query" -p @takumi-rs/core
skilld search "issues:error handling" -p @takumi-rs/core
skilld search "releases:deprecated" -p @takumi-rs/core

Filters: docs:, issues:, releases: prefix narrows by source type.

API Changes

This section documents version-specific API changes in @takumi-rs/core v1.0.0-beta.3. Focus on breaking changes and new APIs that differ from v0.x versions.

Breaking Changes

  • BREAKING: display defaults to inline instead of flex — v1.0.0 changed default layout behavior. Explicitly add display: flex or flex Tailwind class to containers. source

  • BREAKING: Image format options are now lowercase only — 'WebP' → 'webp', 'PNG' → 'png', 'JPEG' → 'jpeg'. All uppercase variants removed. source

  • BREAKING: AnyNode type removed — use Node instead. Generic union type eliminated for type clarity. source

  • BREAKING: PersistentImage type removed — use ImageSource interface instead. Renamed for consistency with web standards terminology. source

  • BREAKING: purgeResourcesCache() function removed — no longer needed with v1's resource management improvements. source

New APIs

  • NEW: emoji option in ImageResponse constructor — controls emoji rendering strategy. Accepts 'twemoji' | 'blobmoji' | 'noto' | 'openmoji' or 'from-font' to use system fonts. Available since v1.0.0-beta.3. source

  • NEW: High-level ImageResponse class API — unified interface extending standard Response object. Works in Node.js, Edge, and browser runtimes with automatic environment detection. source

  • NEW: fromJsx() helper function from @takumi-rs/helpers/jsx — converts JSX to Takumi node tree with extracted stylesheets. Replaces Satori's JSX→SVG pipeline. source

  • NEW: WASM runtime support via @takumi-rs/image-response/wasm import and @takumi-rs/wasm package — enables Takumi in Edge, Workers, and browser environments with module parameter. source

  • NEW: Default fonts included — Geist and Geist Mono fonts loaded automatically by default. Specify custom fonts via fonts option or pass loadDefaultFonts: false to opt out. source

Installation Changes

  • NEW: @takumi-rs/image-response package — high-level API for JSX-based image generation. Replaces direct Renderer usage in most cases. source

  • NEW: @takumi-rs/helpers package — utilities for JSX→Node conversion and DOM manipulation. source

Node.js Binding Updates

In Rust, RenderOptionsBuilder removed in favor of RenderOptions::builder() for more robust builder pattern implementation.

Also changed: WASM module import path changed · @takumi-rs/wasm/next for Next.js · @takumi-rs/wasm/takumi_wasm_bg.wasm for Workers · renderer parameter now accepts pre-instantiated Renderer · module parameter required for WASM environments · signal parameter for AbortSignal support added

Best Practices

  • Reuse the Renderer instance across multiple renders rather than creating new instances each time — significantly improves performance by maintaining resource caches. For Cloudflare Workers, initialize the renderer outside the fetch() handler to avoid repeated initialization on every request. source

  • Preload frequently used images via persistent images to avoid redundant decoding on every render — pass images to the renderer constructor as persistentImages and reference them by key in src attributes or CSS background-image/mask-image properties. source

  • Prefer TTF fonts over WOFF2 for better rendering performance — WOFF2 requires decompression before use while TTF can be used directly. Only use WOFF2 if minimizing file size is more critical than render speed. source

  • Manually extract and fetch external image URLs using extractResourceUrls() and fetchResources() — Takumi does not handle fetching internally, so you must call these helpers and pass fetchedResources to render() or renderAnimation(). source

  • Use stylesheet @keyframes instead of structured keyframes objects when animation definitions should travel with the JSX tree — stylesheets stay embedded in the node while structured keyframes require passing to the renderer separately. source

  • Pass persistentImages to the Renderer constructor, not the render call, for use with renderAnimation() — images passed during construction are available to all animation frames, avoiding per-frame overhead. source

  • Enable drawDebugBorder option when debugging layout problems — renders visible borders around layout elements to diagnose incorrect spacing, sizing, or positioning issues. source

  • Use extractEmojis() helper with a provider (twemoji, noto, etc.) for dynamic emoji rendering when not using the ImageResponse API — the function separates emoji segments from text nodes and prepares them for fetching. source

  • Omit height in ImageResponse or render() to enable auto-sizing based on content — Takumi can calculate height automatically when width is provided, useful for dynamic-height layouts like variable-length lists or text blocks. source