https://jeroen.github.io/notes/tar/Recent content in Tar on ʕ•ᴥ•ʔ Notes from JeroenHugoen-USFri, 24 Apr 2026 00:00:00 +0000https://jeroen.github.io/notes/webassembly-tar/Fri, 24 Apr 2026 00:00:00 +0000https://jeroen.github.io/notes/webassembly-tar/<p><strong>TLDR</strong>: instead of extracting a <code>.tar.gz</code> archive, we can generate a small index file which lists the size and offset of each file in the tar, and use this metadata to mount the tar blob directly via Emscripten&rsquo;s WORKERFS without any copying.</p> <p>For details see: <a href="https://github.com/jeroen/tar-vfs-index">https://github.com/jeroen/tar-vfs-index</a></p> <hr> <h2 id="the-struggle-with-tarballs">The struggle with tarballs</h2> <p>Lots of data on the internet lives in tarballs, often distributed as gzipped <code>.tar.gz</code> files. To get to this data, we have to download the entire <code>.tar.gz</code> file, decompress it, and then iterate through the blob from beginning to end to make copies of the files we need. This is expensive and painful in memory constrained environments.</p>