Files, versions and where your work lives

Extrudo has no account and no server that holds your designs. In the browser they live in the browser's own storage; on the desktop they are files in a folder the app owns. This page covers how that works, how to take a design out and bring one in, and how to keep earlier states of it.

Autosave

You never press Save. A moment after each change, the design is written to your browser's storage, and the word beside its name in the top bar goes from Edited through Saving… to Saved. If a write fails, it reads Couldn't save. Treat that one as a prompt to export the design, because it means the browser could not keep it.

Closing or reloading the tab in the middle of a write is covered too. When the page is hidden with unsaved changes, Extrudo also keeps a rescue copy in a place that writes instantly, and the next time the app starts it saves that copy as the design. Your last edit survives a reload.

Browsers may clear a site's storage when the disk is nearly full. The home screen says Stored on this device when the browser has promised not to, and Storage may be cleared when it has not. In the second case, export the designs you care about.

Taking a design out: Export Design

Home › Files › Export Design downloads the design as an .extrudo file. It is the whole design: the timeline, parameters, bodies' names and colours, any fonts or files you imported, the thumbnail, and every saved version. Import it on another machine or in another browser and you have the same design.

The format is open. It is a zip archive with the design as JSON inside, and docs/file-format.md in the repository describes every field. A design saved by an older Extrudo still opens in a newer one. A design saved by a newer one opens too, and Extrudo tells you if it had to leave out something it does not know.

Home › Files › Export as Script writes the design as TypeScript that rebuilds it, which is useful if you want to turn a design into a program. See the API reference.

Bringing things in

All of these are in Home › Files.

Import Design opens an .extrudo file as a new design. The home screen's Import… card does the same, and takes .f3d and the model files below too: a model file becomes a new design with the Import Model dialog open.
Import Model brings in a STEP file, an STL, 3MF or OBJ mesh, or an OpenSCAD .scad file, as bodies in the current design. A STEP file keeps its exact surfaces. A mesh becomes a mesh body and must be closed. An OpenSCAD file is compiled in your browser, and its customizer variables show up as fields you can change. The Up setting says whether the file's up is Z or Y, and a mesh has a Units setting. An .f3d file picked here opens as a new design instead, with its parameters, sketches, pulled solids, fillets and chamfers; a notice says what came across.
Import Drawing needs an open sketch. It reads an SVG or DXF file and adds its lines and curves to the sketch, at the Scale and Units you choose. Fixed (on by default) pins the curves where they are, so they do not move when you add constraints.
Canvas lays a picture on a plane for you to trace. Calibrate sets its real size from two clicks and the distance between them.

The imported file is stored inside the design, so exporting the design carries it along.

Version history

A version is a named snapshot kept inside the design. Press Ctrl+S, or open Home › Versions › Version History or the clock beside the design's name, to reach the Versions dialog.

The Versions dialog with two saved versions

Save version keeps the design as it is, with an optional Description (Enter saves). The dialog closes and a message says Saved V1. Open it again to see the list.
Restore brings an older version back into the design. The state you had is saved as a version first, and one Ctrl+Z undoes the restore.
Open copy opens the version as a new design and leaves the current one alone. Use it when you want to take a different direction without losing the first.
The bin button deletes one version. After ten, Delete older versions offers to keep the newest ten.

Versions are not backups against losing the browser's storage. They live in the same place as the design, but they travel with the .extrudo file.

Linked folders

Browsers that allow it (Chrome and Edge) can keep a copy of your designs as real files. On the home screen, Linked folder › Link a folder… asks you to choose a folder. From then on:

the folder's .extrudo files are listed on the home screen, and clicking one opens it;
Home › Files › Save to Linked Folder links an open design to the folder;
a linked design is written to its file after each autosave, at most every ten seconds.

The browser's own copy stays the main one. If the folder is unreachable (the browser can lose permission after a restart), the home screen shows Reconnect. If the file changed on disk since Extrudo last wrote it, nothing is overwritten. A message says the file changed, and you choose Load from disk or Overwrite. Unlink the folder leaves the files where they are.

This is handy for keeping designs in a synced folder, or in a repository. Firefox and Safari do not offer folder access, and there the tile and the section are not shown.

Offline, and updates

After your first visit, Extrudo keeps itself in your browser, so it opens without a connection, and the CAD kernel is already there. The one exception is OpenSCAD import, which downloads its compiler the first time you use it. After that it works offline too.

When a new version of the app is out, a message says A new version of Extrudo is ready. with a Reload button. Nothing changes until you press it, so you will not lose work to a surprise reload. Reload first saves every open design, and stops if a save failed.

Examples

The home screen's More examples… lists designs to open, take apart and change. Each one opens as your own copy. The same designs are on the examples page, where Open in Extrudo goes to #/example/<name> in the app, for instance https://app.extrudo.org/#/example/plate. The link is not left in your history, so Back goes to where you were before it.

If you would rather be guided, start with the first tutorial.