Fix nix flake check

.woodpecker.yaml

@@ -2,4 +2,4 @@ steps:
   - name: check
     image: nixpkgs/nix-flakes
     commands:
-      - nix flake check
+      - nix flake check -L --all-systems

blackbox.yml

@@ -0,0 +1,44 @@
+---
+modules:
+  http_2xx:
+    prober: http
+  http_post_2xx:
+    prober: http
+    http:
+      method: POST
+  tcp_v4:
+    prober: tcp
+    timeout: 5s
+    tcp:
+      preferred_ip_protocol: ip4
+  tcp_v6:
+    prober: tcp
+    timeout: 5s
+    tcp:
+      preferred_ip_protocol: ip6
+  tcp_connect:
+    prober: tcp
+  pop3s_banner:
+    prober: tcp
+    tcp:
+      query_response:
+        - expect: "^+OK"
+      tls: true
+      tls_config:
+        insecure_skip_verify: false
+  ssh_banner:
+    prober: tcp
+    tcp:
+      query_response:
+        - expect: "^SSH-2.0-"
+  irc_banner:
+    prober: tcp
+    tcp:
+      query_response:
+        - send: "NICK prober"
+        - send: "USER prober prober prober :prober"
+        - expect: "PING :([^ ]+)"
+          send: "PONG ${1}"
+        - expect: "^:[^ ]+ 001"
+  icmp:
+    prober: icmp