{"id":3596,"date":"2026-06-24T14:24:03","date_gmt":"2026-06-24T12:24:03","guid":{"rendered":"https:\/\/blog.tomayac.com\/2026\/06\/24\/guest-blog-post-on-cross-origin-storage-in-transformersjs\/"},"modified":"2026-06-24T14:24:03","modified_gmt":"2026-06-24T12:24:03","slug":"guest-blog-post-on-cross-origin-storage-in-transformers-js","status":"publish","type":"post","link":"https:\/\/tomayac.com\/wordpress\/2026\/06\/24\/guest-blog-post-on-cross-origin-storage-in-transformers-js\/","title":{"rendered":"Guest blog post on Cross-Origin Storage in Transformers.js"},"content":{"rendered":"\n\t\t\t

I'm very excited to share a guest post I wrote for the Hugging Face \ud83e\udd17 blog! The post is called \ud83d\udc49\u00a0Experimenting with the proposed Cross-Origin Storage API in Transformers.js<\/a>\u00a0\ud83d\udc48! This proposed new browser API, navigator.crossOriginStorage.requestFileHandle(hash)<\/code>, has the potential of revolutionizing the Web, a little bit at least. Learn more by reading the Explainer for the Cross-Origin Storage (COS) API<\/a>.<\/p>\n

And Transformers.js aren't alone with experimenting with this, they're joined by WebLLM<\/a> (docs), wllama<\/a> (code), Flutter<\/a> (code), and Emscripten<\/a> (docs).<\/p>\n

In a nutshell, this is the usual flow of using the API:<\/p>\n

const<\/span> hash =<\/span> {<\/span>\n  algorithm<\/span>:<\/span> 'SHA-256'<\/span>,<\/span>\n  value<\/span>:<\/span> '8f434346648f6b96df89dda901c5176b10a6d83961dd3c1ac88b59b2dc327aa4'<\/span>,<\/span>\n}<\/span>;<\/span>\n\ntry<\/span> {<\/span>\n  const<\/span> handle =<\/span> await<\/span> navigator.<\/span>crossOriginStorage.<\/span>requestFileHandle<\/span>(<\/span>hash)<\/span>;<\/span>\n  \/\/ Cache hit! Get the file as a Blob and use it directly.<\/span>\n  const<\/span> fileBlob =<\/span> await<\/span> handle.<\/span>getFile<\/span>(<\/span>)<\/span>;<\/span>\n}<\/span> catch<\/span> {<\/span>\n  \/\/ Cache miss. Download from network, then store for next time.<\/span>\n  const<\/span> fileBlob =<\/span> await<\/span> fetch<\/span>(<\/span>'https:\/\/cdn.jsdelivr.net\/...\/ort-wasm-simd-threaded.asyncify.wasm'<\/span>)<\/span>\n    .<\/span>then<\/span>(<\/span>r<\/span> =><\/span> r.<\/span>blob<\/span>(<\/span>)<\/span>)<\/span>;<\/span>\n  const<\/span> handle =<\/span> await<\/span> navigator.<\/span>crossOriginStorage.<\/span>requestFileHandle<\/span>(<\/span>\n    hash,<\/span>\n    {<\/span> create<\/span>:<\/span> true<\/span>,<\/span> origins<\/span>:<\/span> '*'<\/span> }<\/span>,<\/span>\n  )<\/span>;<\/span>\n  const<\/span> writableStream =<\/span> await<\/span> handle.<\/span>createWritable<\/span>(<\/span>)<\/span>;<\/span>\n  await<\/span> writableStream.<\/span>write<\/span>(<\/span>fileBlob)<\/span>;<\/span>\n  await<\/span> writableStream.<\/span>close<\/span>(<\/span>)<\/span>;<\/span>  \n}<\/span><\/code><\/pre>\n
\"The<\/p>\n\n\t\t\t
\t\t\tI’m very excited to share a guest post I wrote for the Hugging Face \ud83e\udd17 blog! The post is called \ud83d\udc49\u00a0Experimenting with the proposed Cross-Origin Storage API in Transformers.js\u00a0\ud83d\udc48! This proposed new browser API, navigator.crossOriginStorage.requestFileH…<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"intlwemo_wallet_address":"","footnotes":""},"categories":[1],"tags":[],"class_list":["post-3596","post","type-post","status-publish","format-standard","hentry","category-uncategorized"],"_links":{"self":[{"href":"https:\/\/tomayac.com\/wordpress\/wp-json\/wp\/v2\/posts\/3596","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/tomayac.com\/wordpress\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/tomayac.com\/wordpress\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/tomayac.com\/wordpress\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/tomayac.com\/wordpress\/wp-json\/wp\/v2\/comments?post=3596"}],"version-history":[{"count":1,"href":"https:\/\/tomayac.com\/wordpress\/wp-json\/wp\/v2\/posts\/3596\/revisions"}],"predecessor-version":[{"id":3597,"href":"https:\/\/tomayac.com\/wordpress\/wp-json\/wp\/v2\/posts\/3596\/revisions\/3597"}],"wp:attachment":[{"href":"https:\/\/tomayac.com\/wordpress\/wp-json\/wp\/v2\/media?parent=3596"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/tomayac.com\/wordpress\/wp-json\/wp\/v2\/categories?post=3596"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/tomayac.com\/wordpress\/wp-json\/wp\/v2\/tags?post=3596"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}
\n\t\t\t\t\"Thomas\n\t\t\t\tThis post appeared first on https:\/\/blog.tomayac.com\/2026\/06\/24\/guest-blog-post-on-cross-origin-storage-in-transformersjs\/<\/a>.\n\t\t\t<\/p>\n\t\t","protected":false},"excerpt":{"rendered":"