How did adding the devenv package make my system start to trust devenv.cachix.org

[idrisr]

Hello, I'm trying devenv for the first time to integrate some git-hooks into to my flake-based project. On my nixos machine, I added devenv to environment.systemPackages and then ran devenv init, per the instructions on the setup page.

My question is about the final line from the stdout from devenv init, which I've pasted blow. How did my system start to trust devenv.cachix.org as a substituter / binary cache? My prior understanding was that I would need to explicitly add additional trusted nix binary caches in my config under nix.settings.trusted-substituters and nix.trusted-public-keys to start using a new cache. I didn't add any trusted-substituters or binary-caches to my config, so I'm quite surprised to see that devenv is using devenv.cachix.org.

➜ devenv init
• Creating devenv.nix
• Creating devenv.yaml
• Creating .envrc
• Creating .gitignore
direnv: loading ~/fun/visual-preview/.envrc
direnv: loading https://raw.githubusercontent.com/cachix/devenv/95f329d49a8a5289d31e0982652f7058a189bfca/direnvrc (sha256-d+8cBpDfDBj41inrADaJt+bDWhOktwslgoP5YiGJ1v0=)
direnv: using devenv
direnv: .envrc changed, reloading
direnv: ([/nix/store/h960xs3n0qh0809620kp9955sh56rgp1-direnv-2.34.0/bin/direnv export zsh]) is taking a while to execute. Use CTRL-C to give up.
• Using Cachix: devenv
• Trusting devenv.cachix.org on first use with the public key devenv.cachix.org-1:w1cLUi8dv3hnoSPGAuibQv+f9TZLr6cv/Hm9XgU50cw=
direnv: updated devenv shell cache

[sandydoo]

If you're a trusted user, then devenv will add the --extra-substituters and --extra-trusted-public-keys arguments to its internal nix commands.

If you're not a trusted user, then you'll be provided with instructions on how to add the substituter manually.