diff --git a/dev/dev-features.sh b/dev/dev-features.sh
index 8eba0e8..b06ce4f 100644
--- a/dev/dev-features.sh
+++ b/dev/dev-features.sh
@@ -53,6 +53,15 @@ ls -al /var/lib/nixos-containers/nb-test
 # The container root filesystem on NixOS systems with stateVersion < 22.05
 ls -al /var/lib/containers/nb-test
 
+# Start a shell in the context of a service process.
+# Must be run inside the container (enter with cmd `c`).
+enter_service() {
+    local name=$1
+    nsenter --all -t "$(systemctl show -p MainPID --value "$name")" \
+      --setuid "$(id -u "$name")" --setgid "$(id -g "$name")" bash
+}
+enter_service clightning
+
 #―――――――――――――――――――――――――――――――――――――――――――――――――――――――――――――――――――――――――――――――
 # bitcoind
 run-tests.sh -s bitcoind container
diff --git a/modules/fulcrum.nix b/modules/fulcrum.nix
index 0cbb87d..592757a 100644
--- a/modules/fulcrum.nix
+++ b/modules/fulcrum.nix
@@ -126,6 +126,7 @@ in {
         Restart = "on-failure";
         RestartSec = "10s";
         ReadWritePaths = cfg.dataDir;
+        ProcSubset = "all"; # Fulcrum requires read access to /proc/meminfo
       } // nbLib.allowedIPAddresses cfg.tor.enforce;
     };