diff --git a/nix/host-modules/hive-c0re/default.nix b/nix/host-modules/hive-c0re/default.nix
index 01362c69..056b28b3 100644
--- a/nix/host-modules/hive-c0re/default.nix
+++ b/nix/host-modules/hive-c0re/default.nix
@@ -13,6 +13,12 @@
 let
   cfg = config.services.hyperhive.c0re;
 
+  caTrust = import ../lib/hive-ca-trust.nix {
+    inherit lib;
+    tlsCfg = config.services.hyperhive.tls;
+    gatewayCfg = config.services.hyperhive.gateway;
+  };
+
   # Privsep splits ownership across users, so git/libgit2's dubious-
   # ownership guard trips on legitimate cross-user reads: hive-priv (root)
   # fetches the hive-core-owned meta/applied repos via nix, and hive-c0re
@@ -105,6 +111,28 @@ in
   imports = [
     ./options.nix
     ./theme.nix
+    # Hive-CA trust for this daemon's outbound TLS. Nothing it is given by
+    # default is https — the forge, matrix and queue URLs all resolve to
+    # plain http or loopback — so this changes nothing on an all-local
+    # hive. It matters for the split-host shape the options invite:
+    # `swarm.matrix.apiUrl`'s own example is `https://matrix.example.com`,
+    # and pointing it (or `statusPublish.natsUrl`) at another hive's
+    # gateway means verifying a leaf signed by a CA generated at runtime,
+    # which no build-time trust store can contain.
+    #
+    # ⚠️ `SSL_CERT_FILE` REPLACES the trust store, and unlike the other
+    # consumers of this helper, hive-c0re already makes a *public*-TLS call:
+    # the OTEL exporter reaches whatever `otel.endpoint` names, typically a
+    # normal internet host. The bundle is system CAs + hive CA precisely so
+    # that path keeps working — narrowing it to the hive CA alone would fix
+    # a case nobody hits yet and break one that runs today.
+    (caTrust.trustBundle {
+      inherit pkgs;
+      name = "hive-c0re";
+      consumers = [ "hive-c0re" ];
+      hostUnit = true;
+      enable = cfg.enable;
+    })
   ];
 
   config = lib.mkIf cfg.enable {