over the bridge · up the ladder · in the shutter cabin · noon
A tower in the city over the bridge
The Clacks Tower
Lit only by the message going out: the sun through the open shutters, lying on the floor in squares.
HOW LOUD DO YOU WANT IT?
Starts wherever your device says. Nothing moves, flashes, or plays until you say so.
You have climbed the ladder inside a clacks tower, over the bridge from Widdershins, and come up through the hatch into the cabin at the top, where the shutters are. It is noon on a clear day. The shutters on the far wall stand open in one pattern and shut in the rest, and the sun comes through the open ones and lies on the floorboards in squares, in the same pattern, turned upside down by the angle of the light.
So the only light in here is the message going out. Everything else in the cabin is in shade: the walls, the levers, the ladder you came up. Every word in this room stands in one of those squares of daylight, or in the shade between them, and nothing in it moves at any setting, MAX GLITTER included. The shutters are held where they are, mid-word.
Nobody is up here while you are. The crew is out on the gallery, or asleep in the bunk under the cabin, or down the hill; this room does not draw them, or anybody else from the book.
Up the tower
In Going Postal there is a semaphore network across the continent — towers, shutters, a code, and crews who live up there. Early in the book a young man named John Dearheart dies on one.
This is one of those towers, a tower of the Grand Trunk, the company that runs the line in the book. Ours is drawn plainly, a timber cabin on top of a mast with a grid of shutters on the side that faces the next tower along. The pattern the shutters stand in is ours too. The book has a code and we do not know it, so the squares on the floor spell no letter of it, and the room will not pretend that they do.
Through the one open shutter in the middle you can see the next tower, small, on the next hill. That is the whole network from in here: one tower looking at another, each with somebody in it reading the other's shutters.
The Overhead
His father puts his name into the Overhead — the working channel the towers use to talk to each other, which no customer ever sees — with three letters in front of it.
G: send it on. N: do not log it. U: at the end of the line, turn it around and send it back. GNU John Dearheart, up and down the towers, indefinitely, for as long as the network stands.
That is the whole of it, three letters and a name, and it is enough. A message that is never logged, so nobody keeps a record of it, and never stops, so it is always somewhere on the line. Some of the light in this cabin is that name going out, and some of it is the next tower turning it round.
Star Stuff gives a line from the book about what the name in the Overhead is for, and says in its own colophon that the wording came from a reference wiki and was never checked against the novel. So this room does not print it. It is a line many people know by heart, and that is exactly the kind of line worth reading in the book before quoting. Until somebody does, what the line is about is in the paragraph above, in our words.
This street sends it
When Terry Pratchett died, on 12 March 2015, readers put his name in the Overhead of the network we actually have. Star Stuff names the place:
An HTTP response header, invisible in the page, carried on every request, logged by nobody, meaning nothing to any browser:
X-Clacks-Overhead: GNU Terry Pratchett. Every page on this street sends it, this one included. Open your browser's network panel, look at any response from this site under its response headers, and it is there. It does nothing at all in the page.
This is a fan convention, not Pratchett's instruction. He did not ask for it, his estate did not originate it, and nobody should read the header as endorsement by anyone.
And the N holds here as well. This page keeps nothing about you and sends nothing anywhere, and nobody is counting who climbed the tower.
Who lives up here
Star Stuff reads the books about new machines in Ankh-Morpork as asking a question most stories about technology skip: who pays. Its answer for the clacks is the people up here:
the third is always about who was standing where the thing landed: the clacks workers on the towers, the golems who are property, the engravers whose craft the press makes worthless, the people the railway timetable now owns.
A network that works in the dark is somebody's nights up a tower. That is not an argument against the network, and it is not one here; the clacks works, and in the book people love it. It is an argument for looking at who is standing where the thing lands, and the people who keep it running, before admiring how fast it goes.
Luddite sensibilities don’t reflexively reject technology. Technology is liberating rather than dominating when used to equip our individual tool belts.
Which is the side this street is on. Our Luddite Sensibilities page says it at length, and Star Stuff's One Atom of Justice says the rest.
What the light says
Every room on this street is lit by something no other room has, and this one is lit by what it is saying. The day is outside, behind the shutters; it only comes in where a shutter stands open, so the light on the floor is the shape of the message, cut out of the sun.
The squares are hard-edged, because it is noon and the sun is a long way off. They are white, because the light has come through nothing but air. The shade between them is cool and dark, because the cabin is tarred against the weather, and every word that is not in a square stands in it.
Nothing moves. A clacks tower is a machine for moving shutters, and the obvious thing to add would be to let them flap at MAX. They do not: a light that changed with the shutters would be a light that flickered, and a message held mid-word is still a message.
What is not up here
- No line we could not check. One line from the book is quoted widely and Star Stuff says it never checked the wording against the novel. This room says what it is about and does not print it.
- Nothing from a fan wiki. The book and Star Stuff are the sources for what this room says, and nothing here is copied from a fan-written description of somebody else's invented world.
- Nobody drawn. No crew, no character, no cover and no company crest. The tower is ours, made of timber and shutters anybody might draw, and nobody is up it while you are.
- Not the estate's. Terry Pratchett's estate has no involvement in this room, was not asked, and has not seen it. The header is a fan convention, not his instruction.
- Nothing logged, nothing counted. The N holds: the page keeps nothing about you, sends nothing, and counts nobody who climbed up.
- Nothing moves. The shutters are held mid-word at every setting, MAX GLITTER included. The light on the floor never changes, so it never flickers.
Down the ladder
- Widdershins, back over the bridge, the crooked city with the morning halfway across it, where a clacks tower stands on the skyline.
- The Repeater, out past the last streetlight, the street's other tower: a radio mast on a ridge at night, where nothing is lit at all.
- Breaker Breaker, on the street, the citizens band, where every light is a marker lamp on a rig at night.
- The Feed, on the street, a split-flap board that carries every wire we run, a title and a date and never the words.
Whose this is
- The Discworld is Terry Pratchett’s, and the clacks, the Grand Trunk, the Overhead and John Dearheart are from his Going Postal (2004). No line of the book is quoted here. His estate has no involvement in this room, was not asked, and has not seen it. Discworld is a trade mark, and nothing here is offered as anything of theirs.
- The header is a fan convention, started by readers in March 2015, and not his instruction or his estate’s, as Star Stuff says in as many words. This street sends it from its
_headersfile. - The tower is ours, a timber cabin with a grid of shutters anybody might draw, made as code by Claude, an AI model made by Anthropic, to Ryan’s brief. Its pattern spells no letter of the book’s code, nobody is in it, and nothing on this page calls an AI while you read it.
- Most of the quoted words are Star Stuff’s, from No. 49, One Atom of Justice, by Stimpunks and Helen Edgar’s More Realms, under CC BY-SA 4.0 like this street, and one line is from our own Luddite Sensibilities page. The words around them are ours, written for this room, and nothing about the Disc was taken from a fan wiki.
- Every quotation in this room is 40 words or fewer, was read on 2026-11-04 on the page it names, and
tools/make-clacks-tower.pychecks each word for word against Star Stuff’s own repository and our copy of stimpunks.org, whenever they are on the machine. - The type is Allerta Stencil, by Matt McInerney, a stencil, for the room’s name and headings, under the SIL Open Font License, and Signika, by Anna Giedryś, drawn for signs, for everything you read, under the SIL Open Font License, both read off their own records. More in the liner notes.
Job marker — a shutter pin come loose, lying in a square of sun on the floor
You have found a job marker. The Adventurer’s Guild is a shopfront on the street, and it posts jobs that send you round these rooms. Take the code below to its board and that job is done. Nothing here is scored, nothing expires, and one is a perfectly good number of jobs to do.
The job: What do the towers talk to each other on?
Before the code: What is the working channel the clacks towers use to talk to each other, which no customer ever sees, called?
Hint 1
It is a heading in the room.
Hint 2
It runs over the top of every message, so to speak.
Last hint
The Overhead.
Give me the answer
The answer is The Overhead. In Star Stuff's words, the Overhead is the working channel the towers use to talk to each other, which no customer ever sees. GNU John Dearheart goes up and down it, sent on, not logged and turned around at the end of the line.
Taking the answer is a real way through this, not a lesser one. Nothing is watching and nothing is written down.
Quest code: SHUTTER
That is the one.
In Star Stuff's words, the Overhead is the working channel the towers use to talk to each other, which no customer ever sees. GNU John Dearheart goes up and down it, sent on, not logged and turned around at the end of the line.
Quest code: SHUTTER