Moving an Eagle library, and what actually survives the move

Eagle stores everything in a single ".library" folder that lives wherever you told it to when you set the app up. Open it and you will find your images sitting as ordinary files, each one paired with a small file that records its tags, folders and notes. That is the useful thing to know before deciding anything: nobody who owns an Eagle library is locked into Eagle, because the files underneath it were never hidden from you in the first place.

This covers how the library is actually laid out, the honest options once you know that, what survives a move and what tends to get flattened, and what happens specifically if you import into Muse.

How is an Eagle library actually laid out on disk?

Eagle's own support documentation puts it plainly: every image you add is placed in the Library, which is fundamental for the images you saved and their respective metadata. In practice that Library is a folder with a .library extension. Finder sometimes shows it as a single icon rather than something you can step straight into, in which case right-click it and choose Show Package Contents, the same trick that opens any Mac app bundle.

Inside, a metadata.json file at the root records your folder tree: names, nesting, and which folder sits inside which. Alongside it sits an images folder, and every item you have ever added gets its own subfolder in there, named after an internal ID rather than the item's title. Open one of those subfolders and you will find the original file exactly as you added it, plus a metadata.json of its own holding that item's title, tags, source link, note, star rating and the folders it belongs to. Folder membership is not the folder the file physically sits in. Eagle keeps that virtually, as a list of folder IDs inside the item's own metadata, which is how one picture can appear in three of your folders without three copies of the file existing on disk.

You are not locked in

That structure is the reassuring part. There is no proprietary container, no encrypted blob, and no requirement that Eagle even be installed to get the pictures back. If Eagle disappeared tomorrow, or you simply stopped being able to open it, every original file would still be sitting in an ordinary folder, openable in Preview or any other app, using nothing but Finder.

What Finder alone will not hand you back is the organising work. Tags, folder membership, star ratings and notes live in those metadata.json files, not in anything a folder view shows you. Recovering the pictures is trivial. Recovering the structure you built around them needs either Eagle itself, or something that can read that metadata the way Eagle does.

What are your options?

Three, in practice, and none of them requires deciding everything today.

Keep using Eagle. The simplest option, and worth stating plainly: knowing your files are ordinary files does not oblige you to leave. Eagle remains a capable, mature library app, and understanding the format underneath it is just good practice for trusting years of work to any piece of software.

Copy the originals out by hand. Eagle has its own Export to Computer command, reachable by right-clicking a selection or a whole folder, which writes the chosen items back out as ordinary files you can put anywhere. It is the cleanest way to get plain files out without touching another app. What it will not carry with it is the metadata: tags, ratings, notes and folder membership stay behind in Eagle's own library, because the exported files are just files again, the same as any picture on your Mac.

Import into another app. Several tools built for people leaving Eagle read the .library format directly, parsing metadata.json rather than asking you to re-tag everything from a plain export. Muse is one of them, covered below.

What actually survives a move, and what gets flattened?

The two things worth being honest about before you switch anything are tags and star ratings, because they behave differently depending on the route you take.

A plain file, dragged out or exported with Export to Computer, carries none of Eagle's metadata with it. No tags, no folders, no rating, no note. Everything you see afterward is whatever the destination app can read from the file itself, plus whatever you type in again by hand.

A purpose-built importer changes that, because it reads metadata.json instead of just the file. Tags usually survive well this way, since Eagle stores them as a plain list of names. Folder structure can survive too, if the importer rebuilds it as nested folders or collections rather than flattening everything into one list. Star ratings are the more likely casualty even here. Eagle scores an item from zero to five stars, and few destination apps have an equivalent field, so a five-point scale usually gets collapsed into something coarser, or dropped altogether.

What happens if you import into Muse

Muse has a direct Eagle importer: point it at your .library folder and it reads the file straight off disk, the same metadata.json structure described above. Your folder tree comes across as nested collections, and an item that lived in several Eagle folders at once lands in all of the matching collections in Muse rather than just the first one. Tags arrive as ordinary tags. Titles, source links and notes carry over where Eagle had them, and so does the date each item was originally added.

Star ratings are the one place this is not a clean move. Eagle's five-star scale collapses into a single favourite marker in Muse, and only for items you rated four or five stars. A three-star rating, or lower, does not survive as anything, which is worth knowing before you rely on ratings to resurface your best work later.

Worth being precise about one more thing, because it is the most common worry people bring to any Eagle move: Muse does not leave your files where Eagle put them. It copies them into its own Muse Library folder, exactly the way Eagle copied them into its library in the first place. You end up with two independent copies on disk rather than one file shared between two apps, which is normal for this category of software and not something specific to Muse. Once you have checked everything came across, the old .library folder is safe to archive or delete, and Export My Library writes any Muse collection back out as plain folders whenever you want it, so the same openness that got you out of Eagle applies going forward too.

One practical note before you start: Muse needs an Apple Silicon Mac running macOS 14 Sonoma or later. It does not run on Intel, so check that first if the machine holding your Eagle library is an older one.