Try It First

nixarchy try <name> runs an application once, to see whether you want it, without adding it to your configuration. Nothing is written to ~/.config/nixarchy/apps.nix, nothing is rebuilt, and when the app exits your system is configured exactly as it was.

It runs from the system’s own pinned nixpkgs – the same tree nixarchy-apply installs from – so what you try is exactly what installing would deliver. A bare nix run nixpkgs#name does not give you that: it resolves the global flake registry to whatever nixpkgs-unstable is today, a version this machine has never seen.

There are two ways in:

• nixarchy try <name> in a terminal.
• Install ▸ Search, then ctrl-t on a package or app row. Enter still queues the selection for install; ctrl-t runs it now instead, in the same terminal the picker is in. The rows that can be tried say so in their preview.

What it is not

Not a sandbox. This is the thing to be clearest about: try runs the same code installing would, with your full user privileges – your home directory, your network, your session. The only thing it spares you is the commitment. For code you do not trust, the answer is a sandbox: nixarchy vm boots a disposable NixOS with real isolation. try is for an app you would happily install and are just not sure you want.

Not gone when it exits. The package is downloaded into /nix/store and stays there until garbage collection. A tried package has no garbage-collection root, so it is pure garbage the moment you close the terminal – nothing references it, and collecting it can never cost you a rollback.

On a machine the installer built, that collection is automatic: the Nix daemon collects when free space falls below 5 GiB, which is the case this setting exists for. You can also do it now, and it is the same operation:

sudo nix-collect-garbage

If you added nixarchy to a machine you already run, none of this is turned on for you – your own collection policy stands, and the command above is the manual version.

Not installed. No launcher entry is created – nothing writes a .desktop file – and the app runs in the terminal you launched it from. Close the terminal and it goes with it. If it should survive that, that is what installing is for.

What can be tried

nixpkgs packages, and the apps in the catalogue that are a package underneath. An app that is really a NixOS module – firefox, docker – has no single program to run; enabling it configures the system, which only a rebuild can do. Flatpaks likewise have no package attribute to run. nixarchy try says so rather than guessing at something to execute, and the picker’s ctrl-t gives the same answer.

Keeping it

Install it the way you always would: pick it with enter in Install ▸ Search, or nixarchy-pkg-add <name>, then nixarchy-apply. Because try ran the pinned tree, the version you tried is the version that installs.