Define the monoserver as a systemd service

Much better than manually running:

```shell
$ cd ~/briefcase && git pull --rebase origin master
$ nix-rebuild switch
$ nix-build -A zoo
$ pkill zoo
$ ./result/zoo &
$ job -l
$ disown %<job-number>
```

1 files changed, 10 insertions, 0 deletions

diff --git a/nixos/socrates/configuration.nix b/nixos/socrates/configuration.nix
index f88ebe1222e4..7d958dbdeb73 100644
--- a/nixos/socrates/configuration.nix
+++ b/nixos/socrates/configuration.nix
@@ -142,6 +142,16 @@ in {
   #   };
   # };
 
+  systemd.services.zoo = {
+    enable = true;
+    description = "Run my monoserver";
+    script = "${briefcase.zoo}/zoo";
+    environment = {};
+    serviceConfig = {
+      Restart = "always";
+    };
+  };
+
   services.gitDaemon = {
     enable = true;
     basePath = "/srv/git";