Aether
Nexus
Where the library comes from.
Aether plays what a server hands it. Nexus is that server — a Mac app that sits in the menu bar, reads the folders your films and shows are already in, and serves the original files, untouched, to every Apple device in the house. Point Aether at it and the library you have on disk is the library you have on the sofa.
Built for Aether
Aether
The player Nexus was written for — iPhone, iPad, Mac, Apple TV and Apple Vision Pro. Add the server once and it appears beside whatever else you already watch from.
Nexus is one source among several, not a replacement for the ones you have. Aether merges them all into a single library, so adding it does not mean moving anything.
A menu bar icon, and a web page for the rest
A media server usually means a window you never open and a dashboard you have to learn. Nexus splits the difference: the part you touch every day is a menu bar icon, and the part you touch twice a year is a web page it opens for you.
Nexus
Running
Libraries
Now playing
Settings…
Quit Nexus
It lives in the menu bar
No Dock icon, no window in the way. The drop up there says the server is running, what it is scanning and who is watching right now — and that is the whole of the everyday interface.
Settings are a page on your Mac
Choose Settings and Nexus opens a local web UI in your browser: libraries, folders, people, metadata. It is served by your own Mac, so the same page is there from the sofa or another room with nothing to install.
It gets out of the way
Start it once and it comes back with the Mac. Nothing to keep open, nothing to sign into, and no account anywhere — the server is a program on your machine, not a service you subscribe to.
From a folder to your television
Point it at your folders
Add the folders your films and shows already live in. Nexus reads them where they are: nothing is copied, renamed, or moved into a library of its own, and your naming survives contact with it.
It works out what everything is
Files are matched to titles, seasons and episodes, and each one collects its poster, year, cast and description. Whatever could not be matched is listed rather than quietly hidden, so you can correct it instead of going looking for it.
Your devices find it
Aether on the same network sees the server and asks for the library. One sign-in per device, and then a phone, an Apple TV and a Vision Pro are all reading the same catalogue and the same watch progress.
It sends the file, not a version of it
Press play and Nexus serves the original bytes across your network. No transcode is started, so the Mac never spins up, and the film arrives exactly as it is on disk.
That last step is the design rather than a shortcut. A server that transcodes is sized by how many people are watching at once; a server that only sends bytes is sized by your network, and your network was already fast enough.
The server sends. Aether plays.
Every media server eventually meets a file its clients cannot open, and the usual answer is to re-encode it on the server — slowly, hotly, and at some cost to the picture. Aether does not need that answer, because the hard part already runs on the device you are watching on.
PrismCore does it on the device
Aether’s own engine repacks MKV and MPEG-TS into what Apple’s player accepts, on the iPhone or the Apple TV itself. The server is never asked to convert anything, because by the time it would matter the conversion has stopped being necessary.
Nothing is re-encoded
The picture and the sound arrive as they were mastered: hardware decode, Dolby Atmos passed through as a bitstream, Dolby Vision engaged on the panel. A transcoding server would have flattened all three on the way out.
A Mac mini is enough
Sending a file is work a machine from ten years ago can do. The reason a media server usually asks for a fast processor is the transcoding — take that away and the requirement goes with it.
How it works
Nothing here hides behind a service. A folder you approve, a catalogue on the Mac, and a range of bytes over your own network — that is the whole machine.
A catalogue, not a copy
Every file gets an identity in a small database on the Mac, keyed by where it sits inside the folder you approved. Restart the machine, or replace a file with a better rip at the same path, and the entry survives with its poster, its match and your progress still attached.
Bytes, and a range
Playing something is an ordinary request for part of a file. Ask for the middle of a three-hour film and Nexus reads that part and sends it — no session to negotiate, no stream to start, nothing to prepare before a picture appears.
It looks inside your files
A background pass works out what is really in each one: the Dolby Vision profile by number rather than “has Dolby Vision”, HDR10 told apart from HLG, Dolby Atmos objects, every audio and subtitle track. PrismCore does that reading — Aether’s own engine, running here as a separate short-lived process, so a file built to break a demuxer takes down nothing but itself.
Everyone gets their own account
Create people in Settings and tick the folders each of them may see. Signing in returns a token that opens those folders and no others, and removing a grant, changing a password or deleting the person revokes it on the spot rather than at the next restart.
Your network, and only yours
It listens on the Mac itself, and on your local network only once you turn that on. Aether then finds it by name and keeps following it when the router hands the Mac a different address. Nothing is forwarded, nothing is registered, and no address of yours is published anywhere.
It keeps itself up to date
A signed build checks this site once a day and asks before it replaces itself, so an update never lands in the middle of something someone is watching. There is no account behind the check and nothing is reported back.
What’s inside
Films and shows, properly sorted
Seasons, episodes, specials and multi-part films, with posters, backdrops, cast and descriptions filled in for you. A show split across two drives is still one show.
Your files, where they are
Any folder on the Mac, and any drive the Mac can see — an external disk, a NAS mounted over SMB. Nexus reads them in place and never writes into them.
People, not one shared login
Everyone in the house gets their own user, with their own Continue Watching, their own watchlist and their own ratings. What one person watches does not turn up on anyone else’s home screen.
Progress that follows you
Stop on the Apple TV and pick up on the phone at the same second. The position lives on the server, so every device you own agrees about where you got to.
Subtitles it finds for you
Subtitle files sitting next to a film are picked up automatically, and the tracks inside the file are offered as they are — including the picture-based ones, which Aether reads on the device.
It stays on your network
The server listens on your own network and talks to your own devices. There is no cloud service in the middle, no account to create, and nothing about your library leaves the house unless you deliberately open a door for it.
Music, without a second app
The audio in the same folders is browsable as records, artists and tracks. Nothing has to be marked as a music folder and no catalogue is consulted: a track is named by its own tags, and by the Artist / Album / 01 Title layout wherever those are silent. Cover art is read straight out of the file it lives in, so a music library adds nothing to keep backed up.
A library in the browser, too
The server has its own web player. Anyone in the house signs in and gets the same shelves, the same Continue Watching and their own watchlist — which is the answer for the one machine in the house that is not an Apple one.
Apps that aren’t Aether
Nexus was written for Aether, and does not insist on it. Turn on the Jellyfin-compatible API in Settings and the apps written for Jellyfin — Infuse, Swiftfin, Jellyfin’s own iOS, Android and TV clients — sign in to Nexus, browse its libraries and play from them.
One switch, and nothing before it
Until you turn it on, every route under the compatible API answers “not found” — including the one Jellyfin publishes without a password, so nothing advertises that the surface is even there. The switch is read on each request, so turning it back off closes the door on clients that are already signed in.
A translation layer, not a second server
The same accounts, the same per-person folder grants, the same catalogue, the same streaming. There is no separate Jellyfin login to create and no Quick Connect: someone who may see two of your five folders in Aether sees exactly those two in Infuse.
Direct play, said out loud
Every source is advertised as direct play with transcoding off, because that is the truth about this server. Saying it in the protocol’s own words is what stops a client sitting there waiting for a quality ladder that is never going to arrive.
One progress, wherever you watched
What a Jellyfin client reports lands in the same place Aether reads. Start a film in Infuse on the iPad and the Apple TV offers to resume it, at the second you stopped.
It is off until you turn it on, and it is the only part of Nexus that speaks a protocol it did not design. Aether uses the server’s own API, which is where anything new arrives first.
Questions people ask
Do I have to give up Plex or Jellyfin?
No. Aether treats Nexus as one more source and merges it with the servers you already run — the same film on two of them is still one entry in your library. Running both for a while is a perfectly sensible thing to do, and nothing about Nexus assumes you will stop.
Does the Mac have to stay awake?
It has to be awake for anything to play from it, which is true of every media server there has ever been. A Mac mini left running is the usual answer; a laptop works too, and the library is simply unavailable while the lid is shut.
Will it transcode for other apps?
Nexus is written to serve the original file and Aether is written to play it, which is the whole reason neither of them needs a transcoder. A client that can only take a converted stream is not what this server is for.
Is it open source?
Not yet. PrismCore, the playback engine inside Aether, has been open under LGPL from the first day and the intention is the same here — but Nexus's repository is still private. The server is moving fast enough that opening it now would mostly publish decisions about to be reversed. There is no date on it.
Will there be a Windows or Linux version?
Not at first. Nexus is a Mac app because that is the machine it is being built and tested on, and because a menu bar item with a local web UI behind it is the shape that fits there. Nothing in the design rules out other platforms later.
Can I use it with Infuse or Swiftfin?
Yes, once you turn on the Jellyfin-compatible API in Settings. They sign in as they would to a Jellyfin server, with the same username and password, see only the folders that account was granted, and share their progress with Aether. Until you turn it on, that surface does not answer at all.
Get Nexus
Nexus for Mac
One app, and one folder to point it at. It runs on the Mac that already holds your files — an always-on Mac mini is the obvious home for it, but the laptop you are reading this on works too.
Free. Open the download and drag Nexus to Applications.
Just want to watch something?
Nexus is one way to feed Aether, and it is not required. If you already have a server — or just a folder of files on your phone — Aether plays from those today.
See AetherNexus is built by Václav Zmrhal · zmrhal.cz