Subscriptions and the app

What the official app keeps installed, how the library syncs between devices, and why some items cannot be installed with one click.

A subscription is “keep this on my devices”. The official app reads your subscriptions, downloads what they point at, and keeps them up to date.

What can be subscribed to

Three of the eight content kinds, and the closed list is load-bearing:

Kind
asset
mod
collection ✓ — subscribes to everything in it

A server is not something you install. An article is not something a device holds a copy of.

Subscribing to a collection

Subscribing to a collection creates item subscriptions on your behalf for its members. Those remember which collection created them, so removing an item from the collection — or unsubscribing from the collection itself — cleans up correctly rather than leaving orphans installed.

Items that opt out

An item can set subDisabled, which means the app offers only a manual download for it.

It exists because the install path is per-app — a plugin describing where a mod file goes for that game — while the failure is per-item: a mod that ships an installer executable, or lays its archive out differently from everything else for the same game, cannot be placed correctly even though every other mod for that game can. Rather than let it install wrongly and break your game, its team can say so.

Syncing between devices

The app polls with a revision watermark and gets back only what has changed since. That is what lets a device poll every minute without transferring the whole library, and what makes a subscription you created in the browser show up on the desktop within one poll.

A response can also declare itself full rather than a delta, which tells the app to drop anything it is holding that is not in the list.

An item can have a subscription and nothing to install

A subscription outlives the release it was made against. An item whose only release is later hidden still has a live subscription, and the app renders it as “nothing to install yet” rather than failing.

Installs

An install is a sandbox on one of your machines: a game, a set of subscribed items deployed into it, and launch options.

Concept
Deploy strategy How files are put in front of the game — copied directly (backing up whatever they displaced), or linked so the game folder is made of pointers
Environment Whether the sandbox is a player’s game (client), a dedicated server (server), or accepts both (shared)
Launch options Declarative and entirely optional; what each key means is decided by that game’s launch plugin

The environment is not decoration: a dedicated server and a player’s game are the same files arranged differently, and a manager that cannot tell them apart offers everybody both halves of every list.

Downloads

What a device is downloading is a display snapshot, not a queue we drive. The queue lives on the device and is the authority for everything; the snapshot exists so you can check on your phone whether the modpack your desktop started has finished.

Note what a download row does not carry: no URL, no filesystem path, no device identifier beyond your own label for the machine. A path would put your username and drive layout into a row.