diff --git a/lib/networks.conf b/lib/networks.conf
new file mode 100644
index 0000000..ceca92d
--- /dev/null
+++ b/lib/networks.conf
@@ -0,0 +1,19 @@
+# lib/networks.conf — network profiles for proxmox-scripts
+#
+# Maps a VLAN tag to the DNS servers that network uses, so every LXC gets the
+# right resolvers automatically — even when it pulls its IP via DHCP. This is
+# looked up by lib/build.func from the VLAN tag entered during installation.
+#
+# To add a network, add one line. Columns are whitespace-separated:
+#
+#   tag      VLAN tag entered at install time. Use "none" for the untagged
+#            network (i.e. when the VLAN prompt is left empty).
+#   subnet   CIDR of the network. Informational — shown during install.
+#   dns      DNS servers, comma-separated (no spaces).
+#
+# Precedence note: an explicit NAMESERVER=... passed via env always wins over
+# the profile. The profile only fills in DNS when none was given by hand.
+#
+# tag    subnet            dns
+none     192.168.0.0/24    192.168.0.4,192.168.0.5
+20       10.11.20.0/24     10.11.20.44,10.11.20.55