La Bidouillerie

A welcome page. When the first mission opens, a page finally says what you are building: a robot vacuum, mission after mission, which will one day have to clean a house, room by room, on its own. It also reminds you that the house already exists, behind the “House” button. Until now, the word “vacuum” appeared nowhere before the padlock on the pinball machine.

Drawings to pin up. Several steps of the demo now have an orange line under their instruction: “See the drawing”. One click pins the drawing on screen, without opening the Encyclopaedia: you keep it in front of you while you wire, and you move it wherever you like. The first wiring of The solenoid, the push button in Finding the beat, fitting and wiring The contact breaker, the four steps of Two lines, and on the pinball machine, the walls of The shooter lane, drawn in four views without a word. The pinned window is wider, too: the drawing reads at the size it was drawn.

Fitting the contact breaker, better worded. The step mentioned a “small blade sticking out” that the part does not have, and gave the wrong direction. It now says: under the head of the plunger, the green rod pointing towards the solenoid. The mission's introduction, its Encyclopaedia page and the drawing all say the same.

The hand comes back sooner. In the first missions, the hand showing the gesture waited ten seconds without a click before coming back. Turning the camera a little was enough for it never to return. It now comes back after five.

The wheels no longer cheat. The contact between the wheels and the floor created energy the motor never gave. It has been redone: a motor too weak for its load stalls, a robot pushed by hand stops as it should, and the brushroll no longer pushes the robot along — it rubs the floor.

And a few finishing touches. “Load” and “Save” now only show the saves of the machine you are working on: robots for the robot, pinball tables for the pinball machine. Shafts can be painted, like the other parts, and painting a part stops at that part: whatever is mounted on it keeps its colour. The sparks of the contact breaker follow the robot instead of leaving a trail behind it. And the Encyclopaedia tells the story of the solenoid, from Ampère to Charles Page's electric locomotive in 1851, with a photograph of the patent model he filed in 1853.

Coming with early access: from the real motor to the reduction gear. After the bench, the motor goes on the robot. Driving the wheels directly, it does not move it: it spins at 15,000 revolutions per minute, but with no strength. One pulley, then two stages: the robot sets off, far too fast, and struggles as soon as it sweeps. Then the reduction gear, three stages of gears in a case whose holes are numbered and whose cheeks are lettered, like a game of battleships: 128 turns of the motor for one turn of the wheel, and the robot moves at a steady pace, around 80 revolutions per minute, while it sweeps.

A view for playing pinball: J. On the pinball machine, the J key switches to the play view: the table fills most of the screen, seen from where the player stands, with the backbox beside it on the left. The build interface fades away; J again, and you are back at the bench as you left it. With the power on, the shortcut line also gives the keys: left Ctrl and right Ctrl for the flippers, left Shift and right Shift to nudge the cabinet. Until now, only two Encyclopaedia pages mentioned them, and one player searched it for “CONTROL”.

The pinball missions check more closely before ticking a step. The first wall you placed ticked the shooter lane, wherever it was: one player had closed the lane over a third of its height. It now has to run up beside the plunger all the way to the arch, and the step says how far up to go. The gate goes across the passage at the end of the arch, no longer just anywhere. Each flipper coil goes through its side button, on the 50 V tap, and each flipper must snap up, then drop back when you let go of its key.

And their steps say more. At rest, the left flipper points to 4 o'clock and the right one to 8 o'clock, as on a real table: obvious to anyone who has played hundreds of hours of pinball, not to someone who has never seen one. The side buttons' terminals are now blue, and the step says so. Slingshots have a shape: a triangle whose long side, facing the middle of the playfield, sends the ball back. The drawings on their Encyclopaedia page have been redone in that shape. Your table starts by removing the test rollover left between the flippers. And in English, Japanese and Chinese, it called the rollover a “switch”, the name of another part in the crate: one player fitted two switches, and their lamps could never light up.

The game asks before sending your build. “Ask for help” sent it to AngeloStudio on the click, with no way back: anyone who clicked just to see what help was on offer had already sent their robot. A question now comes up, with “Send” and “Cancel”, and the “To AngeloStudio” button in the Blueprint window asks the same.

On the robot side. You can once again add a battery with the power on, to put a second one in series and watch the robot gain strength: since September, the crate disappeared as soon as the first battery was in. A rolling robot is also much cheaper to simulate. Every contact between a wheel and the floor recalculated the inertia of the whole gear train, several thousand times a second: enough to make the game crawl.

A hand shows the move. In the first days of the Steam Next Fest, half the players left the first mission without fitting anything: there was too much to read before knowing what to do. The text stays, and a drawn hand now shows each move, right where it happens: fold the board away with H, take the solenoid from the crate and fit it on the chassis, push the plunger, run a wire from each of its terminals to red and to black, clip the leads on, then switch on. It only appears if you are stuck on a step for a few seconds, and fades at the first click. You will meet it again in The running gear.

The running gear goes underneath. Many players fitted wheels and bearings on top of the chassis: the paragraph about F and H went unread. These are now the first two steps: fold the board away with H, then flip the chassis over with F. The steps after them are more precise: the two 30 mm bearings go one on each side of the slot, level with its middle, and the 28-tooth gear slides on centred right on the slot, or the gear above will never meet it.

The other missions say when and how. The first turn of the wheel starts by turning the chassis back the right way up. It finally says how to remove a part: a right-click opens its sheet, and the Delete button removes it. The contact breaker starts with H, since the crate only shows the breaker with the board folded away, and reminds you that R turns it while you fit it. The T key, which shows the board from above, now appears in the shortcut line, and pressing it again brings back the previous view.

At the end of The contact breaker, the game says what is missing. Three players out of eight stopped at the very last line, after finding the right remedy: the capacitor was in, the machine would not start again, and nothing said why. An orange line now appears under the step and names the first thing that is wrong: the eaten-away breaker to replace, the battery to put back, the open switch, or the capacitor wired in the current's path instead of beside the contact. The puzzle stays whole: nothing shows until the capacitor is in.

Your year of birth, if you like. When you create a profile, after your first name, the game asks for it and offers to skip. Profiles created earlier see the question once. It is there so we know how old our players are, and if you skip, you are never asked again.

A robot sent by AngeloStudio loads in one click. When AngeloStudio answers you with a robot in the messages, a “Load received robot” button appears next to “Ask for help”. Your robot is first filed with the others, then AngeloStudio's goes onto the bench. It works even in the first missions, where Load and Paste are not available yet. In the messages, that robot takes one line instead of thousands of characters.

Three placements that wrongly went through are now refused. They were found on a robot sent with “Ask for help”. The solenoid and the contact breaker can no longer be fitted under the chassis: their terminals go up to the board, which is above, and fitted underneath, their wires had no way through. A gear no longer goes through the chassis metal: it only passes through the slot, well centred in it. The con-rod no longer goes through the bearing: hooked on the face of the gear turned towards it, it passed through it on every turn.

And two touch-ups. In The running gear, the step for the 28-tooth gear says where to put it: facing the slot, since another gear will come through it to mesh with this one. The pinball's slingshot bands also get their rubber back, in looks as in bounce: a rebuild of the workshop had taken it from them in mid-September.

Ask for help in one click. A button next to the envelope, bottom left, sends your robot just as it is to AngeloStudio through the in-game messages — no need to describe what you built. The answer comes back to the same envelope: you can close the game meanwhile, it will be waiting for you on the same profile. And in the messages, the robot you sent now shows as “Your robot” instead of a long string of characters.

An easier con-rod. In The first turn of the wheel, the flywheel keeps the gear train turning after your hand lets go, so the con-rod's eye never stays still in front of the plunger. The step now says so: if you like, take the flywheel off while you engage the con-rod, then put it back.

What blows up is seen and heard. An LED, a resistor, a capacitor or a bulb that gives out now puffs a little smoke along with its crack. The playfield bulb, plugged by mistake into the coils' 50 V, simply went dark: it now pops, its glass turns black like a real bulb whose filament has melted, and it stays burnt until you replace it — cutting the power used to bring it back to life. An LED dims gradually instead of jumping from one level to the next, and goes dark when you cut the supply; a wire hanging in mid-air no longer burns the whole circuit; and a resistor no longer burns out on a spike: it takes an overload that lasts.

Missions that name the move. On the robot, the first instruction says the solenoid's place does not matter yet; The first turn of the wheel starts with two dismantling steps instead of a paragraph people missed; the con-rod's ghost lies down on the side where it will fall, and R moves it to the other; a solenoid set too far now makes the con-rod let go, instead of jamming the wheel while ticking the step; The contact breaker says how to get a new one, and the timing dials which way to face. On the pinball, the first step starts with H, which opens the mechanical crate, and Guide the ball starts by cutting the power: you never work on a live circuit.

Fairer instruments. The oscilloscope has two real test probes, which you set on any two terminals to read the voltage between them. It counts a part that consumes as positive, whichever way you drew its wire, and its trigger level lowers itself when it cannot be reached. A slider sets the speed of the charges on screen, from ×1 to ×30, without changing anything in the circuit. A capacitor's card gives its capacitance the way its can does, “2200 µF”; a gate's card shows both its directions side by side, the active one in green; an open card no longer changes text size before your eyes. And two finishing touches: a wire raised two notches no longer shows its copper outside the sleeve, and resistors have their Ω back.

The Encyclopaedia, closer to the bench. The drawer thumbnails carry a little book icon that opens the part's page without picking the part up. Schematic plates can be pinned in a floating frame that stays in view while you wire. “In parallel” is finally explained where it is mentioned, and a link opens the right tab directly. A new page, Energy, says what a joule is — roughly an apple lifted by one metre — and that energy is never created: it changes form. And the French text has all its accents back.

More comfort. The game ran uncapped, at several hundred frames per second: the graphics card drew frames the screen never showed, and heated up for nothing. It now locks to your screen's refresh rate — 60, 144 or 200 frames per second. With several screens, a Screen row under the sound settings puts the game on the one you choose.

Coming with early access. The workshop screen now shows, closed, the workshops the full game will add. A darts machine to wire from the mains down to the 5 V of its logic — diode bridge, smoothing, regulator, then the sixteen-wire matrix in which every dart closes a crossing. And an electronics bench: the capacitor that fills and empties, the transistor no finger operates, then the astable multivibrator that makes two LEDs blink on their own. Their pages are already in the Encyclopaedia: the diode and the bridge, the regulator, the matrix, the transistor, the potentiometer, the astable.

The game now speaks eight languages. French, English, Spanish, Brazilian Portuguese, Russian, Simplified Chinese, German and Japanese: every text of the game and every one of the eighty-nine encyclopaedia pages, in each of them, with the vocabulary of the workshops and the pinball halls of each country rather than a word-for-word rendering. Eight flags on the players screen; a Windows in one of those languages starts in it — which it did not until now: every newcomer started in French whatever their system, a German player left after thirty-eight seconds, and that is how we found out. Russian has its Cyrillic, Chinese and Japanese each have their own font — they share thousands of characters that are not drawn the same way, and a Japanese reader spots a Chinese-drawn page at a glance, so the game keeps them apart. Every language after English is a first, complete, unreviewed pass: if a sentence reads wrong to you, the message board is there for that.

The flipper hits like a flipper. Its bat had no speed limit of its own: it went as fast as the frame rate allowed, and the ball sometimes went straight through it. The coil now obeys the law of every electromagnetic actuator — its pull drops with the plunger's speed and vanishes at a metre per second — and the bat peaks near four thousand degrees per second, the order of a real table, on any machine. The slingshot rubber is a real collider along its whole length, not a drawing; slingshots and bumpers strike the same at twenty frames per second as at five hundred, because the circuit and the mechanics now advance on the physics step instead of once per frame. A kicker keeps the orientation you gave it, a free bat no longer spins for several turns when you pull its con-rod, and hooking that con-rod no longer takes ten minutes.

Wiring, tidied. A wire pulled from the middle of another one now joins it: the crossed wire is split in two at that point, the three meet, and the new wire takes the colour of the one it extends — from its end or from its middle, straight or diagonal. Plain wires no longer carry a ball at each end; the trace of a wall has the thickness of the wall; the ghost of the wire you are drawing shows along its whole length; a right-click on the board no longer opens the card of a part hidden under it; Esc closes a part's card; and the paint pot in use is the big one.

The island, a new sandbox part. Pins on the holes you click, a guide wire between them — each side straight or bowed with the mouse wheel while you trace — and a plastic on top that the paint pot colours. It sends the ball into the lane across, as on a real table. It guides, it does not strike.

Missions that read better. The panel shows the steps you have done and the one you are on, not the whole recipe at once. The gate step says you can turn it round. When a mission's parts go on the other surface, playfield or backbox, the game takes you there, camera included. The pinball no longer counts the robot's con-rods, and its last mission no longer empties the table. Text sizes were checked on a 1366 × 768 screen: the drawer description, the part card and the mission panel are readable there now. The Encyclopaedia no longer opens on a three-page category — the tools are with the tools, the notions with the notions — and eight of its pages that showed asterisks show bold instead. And the small line at the bottom left says BDL V1.7.0 2026-09: the date in figures, the same for everyone.

The demo now builds a pinball machine. After the twelve vacuum-robot missions, the workshop opens a second bench: a pinball cabinet, its drilled playfield, its backbox, and the same kit of parts to screw onto them. It is not a different game loop — it is the same one, on a machine you can play once it is built: you trace your walls, you wire your flippers, you arm the transformer, and you shoot the ball.

Five missions, and the table stays playable at every step. The shooter lane and its arch, the gate one ball wide, the two flippers with their con-rods and coils, the walls that bring the ball back to them, then your table: two slingshot bands, two lamps, a rollover switch in each return lane. Nothing locks you out, you can shoot the ball between two parts, and the last mission offers to archive your table.

The pinball parts. Flippers, plunger lane, thin walls straight and curved, posts, gate, rollover switch, slingshot kicker, leaf switch, playfield lamp, upright coil, score reel. A slingshot band is traced like a wall, between its posts; its kicker turns itself parallel to the rubber, and its leaf switches reach out for the elastic. Measured with the coils on the 50 V tap: a ball arriving at one metre per second leaves at three and a half.

The backbox is a mounting surface, like the playfield. An upright perforated plate, its wiring board behind it, and the same gestures: B moves from the playfield to the backbox, F turns over whichever surface you are on, H shows or hides its board. A fifty-five-column ribbon links the two boards: a terminal at the far end of the playfield board is the same terminal at the bottom of the backbox board — nothing to run between them, and nothing to unplug.

The score reel, ten digits on a drum. It fits on the backbox, all its mechanism facing you — drum, ratchet, pawl, coil, cams — and its six terminals behind. One step per coil stroke, not per amp. Two contacts do the rest, and that is where it gets interesting: the carry, closed at 9 only, sends the stroke that takes the units from 9 to 0 on to the tens; the reset, closed everywhere but at 0, passes pulses through until the drum comes back to zero and cuts exactly there. Two reels and three wires, and you count to 99. Nobody will tell you how: that is the whole point.

Every terminal says what it is. Right-click a terminal on a score reel, a relay, a rollover switch, a lamp or a coil: the card no longer says "connection terminal" but "Index 3, one of the five contacts in the cycle — open", and the state follows live. On a table where forty wires look alike, that is what tells you where you are connecting.

Twenty encyclopedia pages for pinball. The parts first — the flipper, the walls, the post, the gate, the rollover switch, the slingshot, the lamp, the score reel, the bumper coil — each with its history, and four drawn plates: the reel from the side, the wiring of two reels that count, the slingshot in three stages, the gate in its lane. Then the ideas: your table is a 1970s electromechanical pinball machine without a single chip, and one page explains what that means — electrical on one side, electronic on the other, and the 1977 tipping point. Seven more pages describe the parts you do not have yet, so you can read the inside of a cabinet before you touch it.

The game draws sixteen times less, and the circuit weighs half as much. On a loaded table — nine bands, eighty-one wires, a score motor turning — each frame issued more than five thousand draws. Kit materials now go to the graphics card in batches, the render no longer runs once per light, the charges running along the wires cost ten times less, and the backbox ribbon only enters the calculation through the links that carry something. Measured on the same table: from eighty to nearly four hundred frames per second.

A circuit with no power costs nothing. Supply off, the electrical solver was running flat out on a circuit where the current was zero everywhere: four frames per second on a furnished playfield. It now rests as long as no source is worth anything, and wakes at the first volt — from four to sixty frames per second on the same table.

Strokes no longer depend on the frame rate. Flippers, plunger, slingshot kicker: all of them hit more weakly when the game slowed down, to the point that at sixteen frames per second the ball no longer made it up the lane. Each of them now advances on the physics step, and returns the same speed at sixteen frames as at three hundred.

Your saves live in the Bidouillerie folder of your Documents. The folder used to be called SLF_ASPI, a name inherited from another game; it is renamed for you on first launch. A red cross deletes a file straight from the load list, after asking. And a pinball table no longer loads onto the robot by mistake, or the other way round — the two grids have nothing in common, and the parts landed anywhere.

The robot missions, gone through one by one. Steps still ticked without your having done what they asked: "both must mesh" counted the gear being fitted, even twenty-five millimetres away from the other; "plunger engaged in its con-rod" counted solenoids on the bench; and the floor test ticked on the round trip, with a battery-less robot, without your having seen any of the problem it exists to pose. Others did not say enough: bring the board back before wiring, and the battery draining in real time, which could stop the machine with nothing to explain it. The panel no longer runs off the bottom of the screen on an eleven-step mission — what went under was the banner that takes you to the next one. And every step you complete makes a small ding: the panel is on the right while you work in the middle.

And the fixes you will notice. The ball no longer jumps over thin walls or over a slingshot rubber. A solenoid whose supply you cut lets its spring push the plunger back out. Wires keep their colour from one session to the next. The rollover switch no longer triggers four millimetres too early. A blown LED stays dark for good. The bumper feels the ball even when it arrives in line with its rods. The frame counter no longer shows itself uninvited — F3 shows it and hides it. And the game closes without waiting a minute when a firewall swallows its last line of statistics.

Coming with early access. You can already see them in the drawer, under a padlock: what makes the logic of a real table — the relay, the contactor and the contact blocks that stack onto it, the score motor and its five index contacts, the bumper, the drop target, the insert.

A part's data sheet now opens with a right-click. Left-click meant two things at once: brief, it opened the sheet; held down, it grabbed the part. Two gestures on one button, and nothing to tell you which one was expected — several players left during the first mission without ever finding how to push a solenoid's plunger.

Left-click now means one thing only: your hand. A brief right-click on a part opens its sheet, a right-click on empty space closes it, and a cross has appeared in the sheet's corner. Three welcome side effects: switches and dials finally have a sheet you can read, you can check a roller's speed without shoving the robot by missing your aim, and nothing opens by accident any more.

The current would not flow. On yesterday's build, connecting the bench supply did nothing at all — no current, from the very first mission. The fault was ours and it slipped in a few minutes before publishing: rebuilding the interface quietly took away a component the whole game relies on to know which machine you are working on. It is fixed, and that rebuild can no longer take it, because it now puts it back itself.

If you downloaded 1.5.1 yesterday, this is the one you want. Nothing else has changed.

The connecting rod no longer leans. A tester found the exact cause: it depended on the order you assembled in. Pinned to the plunger first and then to the gear, the rod ended up three and a half degrees out of true, with its pin no longer square to it. A pin is a pivot — it has one degree of freedom, and its axis stays perpendicular, full stop. Both ways round now give the same, straight assembly.

A loaded robot comes back with its wiring. Since the last version, the electrical layer was quietly dropped on load: the mechanics returned, the board came back bare. Robots saved in between can be repaired by refitting the electrics once and saving again.

Slow motion slows the machine down, it no longer changes it. Pulling the time slider made the motor run smoother — and genuinely faster, up to twice its real speed. It was not showing you your machine any more, it was showing you a different one. Now the readings hold to within a tenth of a percent whatever the setting.

And your computer no longer changes the mechanics. The same fault ran deeper than the slider: a machine at thirty frames per second did not run the same mechanism as one at a hundred and twenty. Everything that moves the world is now clocked in fixed steps, independent of how fast the picture is drawn. On a modest machine, it is the same workshop as anywhere else.

The words say what they mean. The front wheel is a ball caster and no longer an idler — an idler guides a belt and carries nothing. "Press" now says press what, and the shaft step tells you its 15 mm rather than leaving you to count presses.

Five new Encyclopedia entries — bodging, electricity, circuit, voltage, current — and the brushroll finally admits its working range: nothing below 10 rpm, full efficiency from 67 to 200, and beyond that it throws the dirt instead of sweeping it, like a real road sweeper.

Hold Shift and keep the part in hand. Fitting twelve terminals used to mean clicking the same tile twelve times. Hold Shift as you place, and the part comes straight back into your hand — wires above all, since a circuit is wired one strand at a time. Let the key go and everything is as before.

The pin lights up in the hole it is going into. A 32-tooth gear offers twelve crank pins per face, all identical, and until now you fitted the connecting rod and found out afterwards. The pin of the hole you are aiming at now switches on while you approach — and the pins on the face you cannot see are no longer catchable at all. Nobody ever pinned a rod while looking at the other side of a gear.

Clear the bench in one go. There was no way to do it: starting over on a large build meant taking it apart piece by piece. The button is at the end of the top bar, in red, and it asks before it wipes.

An old robot loads without falling apart. When a part can no longer find its place — because the kit has moved since — it is no longer dropped somewhere at random: it is left out, and the game tells you how many are missing and why. Your robot comes back with holes rather than as a heap.

And the English says what it means. The sweeping roller is now a brushroll and the motor part a carbon brush — the same word was doing both jobs, and a tester spent forty minutes building a motor on a mission that asked for a broom. The motor bench texts, the placement refusals and the battery warning are translated too; they were still coming out in French.

Wires stay flat on the board — and cross over each other. They no longer drift upward on their own. If a wire would cut across another one, the game refuses the placement: two wires crossing in the same plane would touch. The up and down arrows then route it over the other, or through the thickness of the epoxy. That is exactly what a multilayer board does, and the hundreds of tiny plated holes on any real board are the passages between layers.

The board turns translucent. The left and right arrows fade it continuously, so you can watch the mechanism living underneath without hiding the board away — and without losing its buttons.

A changeover switch and a reverser. The first one neither opens nor closes: it routes. The second is two changeovers on a single slider, six terminals, and it reverses a motor in one move. The crossing happens in your wiring, not inside the part.

Keyboard shortcuts now follow your keyboard. W picks up a wire — except on an AZERTY layout, where nothing happened and Z did it instead. The game was naming its keys by their position on an American keyboard rather than by the letter printed on them. Every letter key is fixed, on every layout.

The machine has a voice. The motor hums, and its pitch follows the speed; when it strains without turning, it growls instead. That second sound is not decoration — dead spots are one of the things the bench teaches, and until now a stall was silent: you could see it wasn't turning without hearing it push. The connecting rod clacks the instant it seats into the plunger, and the plunger itself rubs as it slides.

The tool board filled up. Needle-nose pliers, wire strippers with their stepped notches, a Phillips screwdriver and a soldering iron with its cable join the hammer and the flat screwdriver. You don't use them — they are there to say what kind of workshop this is. A board holding nothing but a hammer announces carpentry.

Missions no longer tick themselves. Several steps could be completed without doing the thing they described: Find the beat validated without the push button, which is the entire point of that mission; six turns pushed by hand counted with the flywheel still sitting on the bench; ten turns counted whether or not the machine was actually powered. Each of them now checks what it claims.

Brushes have to touch the commutator. Set down beside it they power nothing, and the armature's card says why. Until now it was enough for them to be somewhere on the plate — a brush planted two centimetres from the copper, in mid air, ran the machine as well as a properly seated one. On a real motor, a brush backed off by a millimetre stops everything.

Clicking finally lands where you see the object. The desk lamp and the tools each had a single click box stretched around the whole thing — on a jointed lamp that box was mostly empty air, and the cursor lit up half a metre from the metal. Every piece now carries its own.

The workshop no longer answers you — AngeloStudio does. The word was doing two jobs at once: the place where you repair your robot, and the person you write to. The workshop has replied made it sound like you were chatting with your own bench. The button that sends a robot now reads To AngeloStudio, and messages arrive from a name rather than a place.

And a pile of smaller things that came with 1.3.1 and 1.3.2 and were never written up here: the solenoid no longer shakes when idle, connecting rods pin cleanly, a part can no longer be dropped inside a rod, the belt stopped vanishing into the small pulley, and the game warns you when your battery has run flat instead of letting you wonder why nothing moves.

Coming in the full game: the motor bench. A base, a shaft, two magnets, an armature, a commutator, two brushes — nothing pre-assembled. Three different armatures, each one a lesson in why no commercial motor has a two-segment commutator. It is not in this demo: the parts are there, under lock, and you can see them waiting.

Your robot fits in a single line of text. A Blueprint button, next to Save and Load, turns your build into a string of characters you can paste into a message. Whoever receives it pastes the same line into their game and gets your robot back, part for part. It is what Factorio blueprints do, and for the same reason: showing a build had become harder than making one.

A robot you receive is filed with your own saves, under the name you give it. It does not overwrite what is on your bench — you load it when you want to.

And a “To the workshop” button sends it straight over. One click and the robot lands in the message board. No more hunting for a file on your disk to show what is not working.

Gears that do not mesh no longer count as a success. Turning a wheel by hand used to tick the box even when nothing was driving anything. The steps that ask for a train to follow now check that it actually does.

Charges no longer haunt a wire you removed. Cut the power, change your wiring, switch back on: the current used to reappear along a wire that no longer existed.

A new Encyclopaedia page: the controls. Every key and every mouse gesture in one place — including H, which folds the circuit board away to reach the mechanics underneath, and the difference between a short click and a held one.

The words that stopped people are now explained where they turn up. Three players got stuck on the same three words, each on their own. The chassis slot is now called “the large opening in the chassis”. The idler wheel announces its catalogue name, “the ball caster”. The green plate is a circuit board, no longer an “electrical plate”.

The cursor changes shape over the supply leads. They had always been clickable, but nothing said so: one player hunted for them for eight minutes.

The Encyclopaedia answers better. The word you searched for is highlighted in the page you land on, and the page opens on the tab that contains it. Back returns to the list of results instead of the contents. New page: the chassis, with its real dimensions and the twenty-millimetre grid.

Every game carries a first name. Three children on the same computer were told apart only by a number, and one of them carried on with his sister's game.

The game tells you when a new version is online. The demo did not update itself, and nothing said so.

Six new parts: the brush roller, its housing, the dust bin, two pulleys and a 240 axle. Enough to turn the motorised trolley into a sweeper. The brush scrubs the floor and asks for force — the first part in the kit that costs something, and the one that makes torque tangible.

The belt can be crossed, and the machine runs the other way. R switches it from straight to crossed — a figure of eight, exactly as in the workshops of old. It is the kit's only way to reverse a direction of travel without adding an idler gear.

Two more pulleys: a Ø10 and a Ø60. The four sizes now cover ratios from 1.33 to 6. The Ø10 driving the Ø60 divides speed by six while multiplying torque by as much, without adding a single shaft.

Volume is set part by part. Open a part that makes a noise and a slider appears in its data sheet. You can silence one solenoid to listen to the other. The setting travels with the robot when you save it.

The brush roller scrubs, and its voice follows its speed. The sound rises when it spins fast, drops when it labours, and stops the moment the robot leaves the floor. You hear your machine run out of torque before you read it.

The flywheel is spoked. A solid disc that spins is indistinguishable from one at rest — and it is precisely the part you want to see carrying on when everything else has stopped. Asked for by a player, who was right.

The connecting rod no longer comes off its pin. It drifted away as soon as the machine picked up speed — six tenths of a millimetre at a crawl, fourteen at full tilt.

Solenoids no longer run away. A solenoid beating fast now opposes its own movement, as in real life: the voltage it produces by moving is subtracted from the one feeding it.

Wires that cross now pass over one another. Each wire sits on one of four levels, rising from its terminal and coming back down to the other: a bridge, as on a diagram — except that here it really does pass over.

And a long list of smaller things: deleting a game asks for confirmation, the end-of-course button finally opens the sandbox, wheels no longer fit between the bearings, the flywheel fits anywhere under the chassis, a chassis hole is no longer lost after a dismantling, and every rewritten instruction is translated.

French and English localisation.

First release of the demo.