add vouch-unstable

This is needed mostly during hard forks where unstable software is
needed to test things on test networks like Holesky.

Author: zimbatm

pkgs/vouch/unstable.nix

@@ -0,0 +1,32 @@
+{
+  buildGoModule,
+  fetchFromGitHub,
+  mcl,
+  bls,
+  lib,
+}:
+buildGoModule rec {
+  pname = "vouch";
+  version = "1.8.0-beta.3";
+
+  src = fetchFromGitHub {
+    owner = "attestantio";
+    repo = pname;
+    rev = "v${version}";
+    hash = "sha256-CK6cLXJYMQL+ZRv8bYabgQ0GeDWK8Jcek6d/Wow2LI0=";
+  };
+
+  runVend = true;
+  vendorHash = "sha256-Mp+RA2L4mOe089ceyKh3m5Q8zLsdwyx6geMFrqbn5Dk=";
+
+  buildInputs = [mcl bls];
+
+  doCheck = false;
+
+  meta = {
+    description = "An Ethereum 2 multi-node validator client";
+    homepage = "https://github.com/attestantio/vouch";
+    mainProgram = "vouch";
+    platforms = ["x86_64-linux"];
+  };
+}