diff --git a/flake.nix b/flake.nix
index 58e2561c4..779d437f1 100644
--- a/flake.nix
+++ b/flake.nix
@@ -1,38 +1,45 @@
 {
   description = "Comm flake";
 
   inputs = {
     utils.url = "github:numtide/flake-utils";
     nixpkgs.url = "github:nixos/nixpkgs/nixpkgs-unstable";
   };
 
   outputs = { self, nixpkgs, utils, ... }:
     let
       # Overlays allow for extending a package set, in this case, we are
       # extending nixpkgs with our devShell
       localOverlay = import ./nix/overlay.nix;
       overlays = [
         localOverlay
         (_: _: { commSrc = toString self; } )
       ];
 
       # Since we build for many systems (e.g. aarch64, x86_64-linux), we
       # create a helper function to help facilitate instantiation of the related
       # package set
       pkgsForSystem = system: import nixpkgs {
         inherit overlays system;
       };
 
     # utils.lib.eachSystem helps create a result set of expected flake outputs
     # of the form <output>.<system>
     # https://github.com/numtide/flake-utils#usage for more examples
     in utils.lib.eachSystem [ "x86_64-linux" "x86_64-darwin" "aarch64-darwin" ] (system: rec {
       legacyPackages = pkgsForSystem system;
       inherit (legacyPackages) devShell devShells;
     }) // {
       # these outputs will lack the system suffix (e.g.
       # devShell.aarch64-darwin), thus should be system agnostic such as
       # overlays or utility functions.
       overlays.default = localOverlay;
+
+      nixConfig = {
+        substitutors = "https://comm.cachix.org";
+        extra-trusted-substitutors = "https://comm.cachix.org";
+        trusted-public-keys = "comm.cachix.org-1:70RF31rkmCEhQ9HrXA2uXcpqQKGcUK3TxLJdgcUCaA4=";
+        extra-trusted-public-keys = "comm.cachix.org-1:70RF31rkmCEhQ9HrXA2uXcpqQKGcUK3TxLJdgcUCaA4=";
+      };
     };
 }