= Setting Up Binary Cache
:page-parent: Build and Run
:page-nav_order: 1

// SPDX-FileCopyrightText: 2022 Alyssa Ross <hi@alyssa.is>
// SPDX-License-Identifier: GFDL-1.3-no-invariants-or-later OR CC-BY-SA-4.0

Building Spectrum OS from source can take a very long time.  To avoid
having to wait when building the system to try it out or test patches,
an x86_64 binary cache service is available.  If configured to do so,
Nix will download build outputs from the cache, instead of building
them locally.

Builds are run on the latest NixOS unstable on
https://www.vultr.com/[Vultr], and are signed to ensure authenticity.
The build infrastructure and signing key are accessible by Alyssa Ross
and Puck Meerburg.  Storage is provided by Daniel Kuehn.  Please
https://spectrum-os.org/participating.html[get in touch] if you
encounter any trouble with it.

The binary cache is currently not able to provide logs, due to a
https://github.com/NixOS/nix/pull/6051[Nix bug].

== For NixOS

The following configuration adds the Spectrum binary cache as a
substituter, and tells Nix to trust builds signed with its public key.

[source,nix]
----
{ ... }:

{
  nix.settings.substituters = [ "https://cache.dataaturservice.se/spectrum/" ];
  nix.settings.trusted-public-keys = [
    "cache.nixos.org-1:6NCHdD59X431o0gWypbMrAURkbJ16ZPMQFGspcDShjY="
    "spectrum-os.org-1:rnnSumz3+Dbs5uewPlwZSTP0k3g/5SRG4hD7Wbr9YuQ="
  ];
}
----

== For Non-NixOS Systems

Add the following configuration to /etc/nix/nix.conf:

[source]
----
substituters = https://cache.dataaturservice.se/spectrum/ https://cache.nixos.org/
trusted-public-keys = cache.nixos.org-1:6NCHdD59X431o0gWypbMrAURkbJ16ZPMQFGspcDShjY= spectrum-os.org-1:rnnSumz3+Dbs5uewPlwZSTP0k3g/5SRG4hD7Wbr9YuQ=
----

If you have other binary caches configured besides cache.nixos.org,
make sure to add the Spectrum cache URL and public key to the existing
configuration lines in your nix.conf file.
