The problem
A landline rings everywhere. That was fine when a house had one phone and one number, and it is why most people quietly stopped answering the landline: every call was for someone else, and every ring interrupted everyone.
Mobile phones solved it by giving each person their own number — and created a different problem. Now a child needs a phone to be reachable at home, a grandparent has to remember which of five numbers reaches which grandchild, and the house itself has no way to be called.
What a ladder does
A ladder rings in stages. A call for the kids rings their room for three cycles. If nobody answers, it escalates to the adults for four more. If nobody answers that either, it takes a message.
[[extensions]]
pin = "902118"
label = "Kids"
voicemail = "kids"
[[extensions.steps]]
handsets = ["kids-room"]
rings = 3
[[extensions.steps]]
handsets = ["adults"]
rings = 4Nobody downstairs is interrupted by a call that was answered upstairs in six seconds. And nothing is missed, because the escalation is automatic rather than depending on somebody shouting.
Why this is nicer than a mobile
The caller does not have to know who is home, which phone anyone is holding, or whether a battery is flat. They dial one number and the house works out where the call should go.
That is the part that is genuinely hard to buy. Carriers sell you lines; ladders are about routing, and the routing rules are yours.
Details worth knowing
Stages are measured in ring cycles or in seconds. rings = 3 is roughly
eighteen seconds. Use seconds when the number matters — someone who needs
longer to reach a phone reads better as seconds = 45 than as a ring count.
Groups work anywhere a handset does. adults above is a named set defined
once in handsets.toml, so changing who counts as an adult is one edit rather
than a search.
The first stage is the interesting one. Most households find that ringing one likely phone first — the kitchen — and only then the whole house removes most of the annoyance without missing anything.