diff --git a/flake.nix b/flake.nix
index dba6aeb..1ff7501 100644
--- a/flake.nix
+++ b/flake.nix
@@ -112,6 +112,14 @@
             "sys-kernel-debug.mount"
             "sys-fs-fuse-connections.mount"
           ];
+          # Relax seccomp for .NET services to avoid SIGSYS in LXC
+          systemd.services.btcpayserver.serviceConfig = {
+            SystemCallFilter = [];
+          };
+
+          systemd.services.nbxplorer.serviceConfig = {
+            SystemCallFilter = [];
+          };
 
           # State version
           system.stateVersion = "25.05";