# Civilization101 Blueprint

> A dependency-ordered, source-backed plan for rebuilding technological civilization from a standing start. Civilization is modelled as a dependency graph gated by six physical constraints — temperature, precision, energy surplus, population, containment and information decay — so the order is causal, not chronological. Every step cites sources a reader can hold offline, and the whole site downloads as one file that runs with no network.

140 steps in 8 tiers · 35 builds · 48 field guides · 4 essays · 205 verified books · 17 bulk archives. Updated 2026-10-13.

Every page URL below serves the page as HTML with its full text, and the same content is in the JSON file each entry names, fetchable directly. Licence: CC BY-SA 4.0 for the site's own text, drawings, data and code; photographs carry their own licences, recorded per image in data/plates.json.

Human-readable version of this index: https://civilization101.pipchat.in/roadmap

## Subjects

Every step, guide and build has one home in one of 13 subjects, and each subject is a set of tracks that climb the tiers. A step listed under a second subject is marked cross-listed; a level marked planned is not written yet. Page: https://civilization101.pipchat.in/explore · Data: https://civilization101.pipchat.in/data/sectors.json

### Water & Sanitation

Water kills first and fastest. Plan on **15 litres per person per day**; clarify it, then boil, sun or chlorinate it before anyone drinks; and put the latrine at least **30 m from the water**, downhill and downstream. The sector climbs from a scoop hole and a boiling pot to a city main kept under pressure, and every level keeps faeces out of the water that people drink. Page: https://civilization101.pipchat.in/sector/water

- [Find and store water](https://civilization101.pipchat.in/track/water-find): tier 0: [Find and hold water](https://civilization101.pipchat.in/step/t0-water-find); tier 1: [The first public good](https://civilization101.pipchat.in/step/t1-commonworks) (cross-listed)
- [Make water safe](https://civilization101.pipchat.in/track/water-safe): tier 0: [Make water safe](https://civilization101.pipchat.in/step/t0-water-safe); tier 3: [Make chlorine disinfectant](https://civilization101.pipchat.in/step/t3-chlorine); tier 4: [City water and sewerage](https://civilization101.pipchat.in/step/t4-sanitation) (cross-listed)
- [Sanitation](https://civilization101.pipchat.in/track/sanitation): tier 0: [Separate waste from water](https://civilization101.pipchat.in/step/t0-latrine); tier 4: [City water and sewerage](https://civilization101.pipchat.in/step/t4-sanitation)

### Food & Agriculture

Calories first, then storage. Wild food returns what the land gives: nuts and fish repay the effort, greens at about 40 kcal per 100 g do not. So the sector moves quickly to seed stock, a planting calendar and staples. A harvest is not food until it is stored: grain below about **13% moisture**, and nothing low-acid sealed airtight without pressure canning, because **pH 4.6** is the botulism line. Irrigation, synthetic nitrogen and the cold chain are what let one farmer feed many. Page: https://civilization101.pipchat.in/sector/food

- [Wild food](https://civilization101.pipchat.in/track/wild-food): tier 0: [Forage, trap, fish](https://civilization101.pipchat.in/step/t0-food)
- [Crops and soil](https://civilization101.pipchat.in/track/crops): tier 0: [Secure seed and breeding stock](https://civilization101.pipchat.in/step/t0-seed); tier 1: [Read the year](https://civilization101.pipchat.in/step/t1-calendar), [Open ground and hold fertility](https://civilization101.pipchat.in/step/t1-clear), [Plant staples](https://civilization101.pipchat.in/step/t1-staples); tier 2: [Irrigation and water control](https://civilization101.pipchat.in/step/t2-irrigate); tier 3: [The four-course rotation, field drains and the seed drill](https://civilization101.pipchat.in/step/t3-rotation); tier 5: [Drip and sprinkler irrigation](https://civilization101.pipchat.in/step/t5-drip), [Synthetic nitrogen](https://civilization101.pipchat.in/step/t5-haber) (cross-listed); tier 6: [High-yield varieties, and the Green Revolution's bill](https://civilization101.pipchat.in/step/t6-greenrev); tier 7: [Sustainable intensification](https://civilization101.pipchat.in/step/t7-farming)
- [Protected growing](https://civilization101.pipchat.in/track/protected): tier 3: [Cold frames, hotbeds and the glasshouse](https://civilization101.pipchat.in/step/t3-glasshouse); tier 5: [The modern greenhouse: film, glass and climate control](https://civilization101.pipchat.in/step/t5-greenhouse), [Soilless growing: hydroponics and substrates](https://civilization101.pipchat.in/step/t5-hydroponics); tier 7: [Vertical farms and controlled environments](https://civilization101.pipchat.in/step/t7-cea)
- [Livestock](https://civilization101.pipchat.in/track/livestock): tier 1: [Livestock](https://civilization101.pipchat.in/step/t1-animals)
- [Aquaculture](https://civilization101.pipchat.in/track/aquaculture): tier 2: [Fish ponds: build, fertilise and harvest an earthen pond](https://civilization101.pipchat.in/step/t2-fishpond)
- [Storage and preservation](https://civilization101.pipchat.in/track/food-storage): tier 1: [Preserve the harvest](https://civilization101.pipchat.in/step/t1-preserve); tier 2: [Salt](https://civilization101.pipchat.in/step/t2-salt) (cross-listed), [Fermentation and distilling](https://civilization101.pipchat.in/step/t2-brew) (cross-listed); tier 4: [Refrigeration and the cold chain](https://civilization101.pipchat.in/step/t4-cold)

### Shelter & Architecture

Hypothermia kills in hours, so the first shelter is a small, insulated hut or lean-to. The second is a house that lasts thirty years, built from the subsoil, stone or timber on the site. Earth buildings fail from water, not load: a stone plinth **0.30–0.45 m** high and eaves of **0.45–0.60 m** are the defences. Smoke from open fires indoors kills an estimated **2.9 million people a year** (WHO, 2021), so a chimney is a safety device before it is a comfort. Above level 1, building depends on brick, lime, glass and cement, which are cross-listed from Materials & Chemistry so the whole cascade reads in one place. Page: https://civilization101.pipchat.in/sector/shelter

- [Emergency and temporary shelter](https://civilization101.pipchat.in/track/emergency-shelter): tier 0: [Shelter and body heat](https://civilization101.pipchat.in/step/t0-shelter)
- [Dwellings](https://civilization101.pipchat.in/track/dwellings): tier 1: [Plan the house: sun, air, smoke and damp](https://civilization101.pipchat.in/step/t1-dwelling), [Permanent shelter](https://civilization101.pipchat.in/step/t1-shelter); tier 2: [Masonry house and chimney](https://civilization101.pipchat.in/step/t2-masonry); tier 3: [Framed and glazed building](https://civilization101.pipchat.in/step/t3-frame); tier 4: [Iron-framed and multi-storey building](https://civilization101.pipchat.in/step/t4-ironframe); tier 5: [Steel frame and reinforced concrete](https://civilization101.pipchat.in/step/t5-concrete)
- [Storage and farm buildings](https://civilization101.pipchat.in/track/farm-buildings): tier 1: [Preserve the harvest](https://civilization101.pipchat.in/step/t1-preserve) (cross-listed); tier 2: [Barn and byre](https://civilization101.pipchat.in/step/t2-barn); tier 4: [Refrigeration and the cold chain](https://civilization101.pipchat.in/step/t4-cold) (cross-listed)
- [Building materials](https://civilization101.pipchat.in/track/building-materials): tier 2: [Brick and tile](https://civilization101.pipchat.in/step/t2-brick) (cross-listed), [Lime](https://civilization101.pipchat.in/step/t2-lime) (cross-listed); tier 3: [Cement and concrete](https://civilization101.pipchat.in/step/t3-cement) (cross-listed), [Glass](https://civilization101.pipchat.in/step/t3-glass) (cross-listed)

### Settlements & Planning

A camp laid out on the first day decides whether fire and cholera sweep through it: **45 m² per person**, **2 m** between shelters, a **30 m firebreak every 300 m**, latrines within **50 m** of every shelter and **30 m** downhill of any water, water within **500 m**. The sector climbs from that camp to a planned city: ground above the design flood, plots and streets pegged before anyone builds, fire and zoning rules, and room to grow. Page: https://civilization101.pipchat.in/sector/settlements

- [Settlement and planning](https://civilization101.pipchat.in/track/settlement): tier 0: [Lay out the camp](https://civilization101.pipchat.in/step/t0-camp); tier 1: [Choose the ground](https://civilization101.pipchat.in/step/t1-site), [The first public good](https://civilization101.pipchat.in/step/t1-commonworks) (cross-listed); tier 2: [Plot, street and block](https://civilization101.pipchat.in/step/t2-plot); tier 3: [Fire separation and the building code](https://civilization101.pipchat.in/step/t3-fire); tier 4: [Zoning: separation distances, wind, river and flood](https://civilization101.pipchat.in/step/t4-zoning), [City water and sewerage](https://civilization101.pipchat.in/step/t4-sanitation) (cross-listed); tier 5: [Plan the city before it grows](https://civilization101.pipchat.in/step/t5-city); tier 7: [The compact, connected, resilient city](https://civilization101.pipchat.in/step/t7-city)

### Health & Medicine

Most of the gain comes early and costs little: clean hands, soap, clean births, oral rehydration and enough of the right food. Bleeding is stopped with hard, uninterrupted pressure; a burn gets **20 minutes** of cool running water; a contaminated wound is left open. Germ theory and the microscope (level 3) turn those habits into a discipline. Anaesthesia, antibiotics and vaccines follow only once sterility and a cold chain exist. The science under all of it, from the cell and the anatomy of the body to immunity and epidemics, is in [biology](/guide/biology). Page: https://civilization101.pipchat.in/sector/health

- [First aid and surgery](https://civilization101.pipchat.in/track/first-aid-surgery): tier 0: [Wound care and first aid](https://civilization101.pipchat.in/step/t0-firstaid); tier 4: [Anaesthesia and real surgery](https://civilization101.pipchat.in/step/t4-anaesthesia)
- [Hygiene and disease](https://civilization101.pipchat.in/track/hygiene): tier 1: [Soap](https://civilization101.pipchat.in/step/t1-soap); tier 3: [Germ theory and antisepsis](https://civilization101.pipchat.in/step/t3-germ); tier 5: [Antibiotics and vaccines](https://civilization101.pipchat.in/step/t5-antibiotics)
- [Nutrition and teeth](https://civilization101.pipchat.in/track/nutrition): tier 1: [Prevent deficiency disease](https://civilization101.pipchat.in/step/t1-nutrition), [Teeth: prevent decay, and catch the abscess that spreads](https://civilization101.pipchat.in/step/t1-teeth)
- [Mother and child](https://civilization101.pipchat.in/track/mother-child): tier 1: [Childbirth and infant survival](https://civilization101.pipchat.in/step/t1-midwifery)
- [Medicines](https://civilization101.pipchat.in/track/medicines): tier 2: [Plant medicine and the pharmacy](https://civilization101.pipchat.in/step/t2-medicine); tier 7: [Biology as engineering](https://civilization101.pipchat.in/step/t7-bio)

### Energy

Temperature caps what you can make. Wood fires top out around **600 °C** in practice, which is not enough to smelt; charcoal with forced air reaches **1,200 °C** and beyond; a cement kiln needs **1,400–1,450 °C**. Mechanical power arrives with the waterwheel and the windmill, whose output rises with the cube of wind speed. Electricity is a way of carrying energy, not a source of it. Page: https://civilization101.pipchat.in/sector/energy

- [Fire and fuel](https://civilization101.pipchat.in/track/fire-fuel): tier 0: [Fire, and keeping it](https://civilization101.pipchat.in/step/t0-fire); tier 2: [Charcoal](https://civilization101.pipchat.in/step/t2-charcoal); tier 4: [Coal and coke](https://civilization101.pipchat.in/step/t4-coal); tier 5: [Petroleum and refining](https://civilization101.pipchat.in/step/t5-oil)
- [Mechanical power](https://civilization101.pipchat.in/track/mechanical-power): tier 3: [Water power](https://civilization101.pipchat.in/step/t3-waterpower), [Wind power](https://civilization101.pipchat.in/step/t3-windpower); tier 4: [The steam engine](https://civilization101.pipchat.in/step/t4-steam)
- [Electricity](https://civilization101.pipchat.in/track/electricity): tier 3: [Batteries: from the voltaic pile to the lead-acid cell](https://civilization101.pipchat.in/step/t3-battery); tier 5: [The generator](https://civilization101.pipchat.in/step/t5-generator); tier 7: [Energy without the carbon bill](https://civilization101.pipchat.in/step/t7-energy)

### Materials & Chemistry

What you can make is capped by the hottest fire you can sustain and contain. Cord and containers come first, pottery and the kiln next, then brick, lime, metal and glass. Pure iron melts at **1,538 °C**, which no bloomery reaches, so early iron is worked solid rather than cast. Salt, alcohol, acids and alkalis are the chemical prerequisites for soap, glass, batteries and medicine. Page: https://civilization101.pipchat.in/sector/materials

- [Fibres, textiles and leather](https://civilization101.pipchat.in/track/fibres): tier 0: [Cordage](https://civilization101.pipchat.in/step/t0-cord); tier 1: [Fibre, thread and cloth](https://civilization101.pipchat.in/step/t1-textiles), [Tanning and leather](https://civilization101.pipchat.in/step/t1-tanning)
- [Ceramics and glass](https://civilization101.pipchat.in/track/ceramics-glass): tier 0: [Containers](https://civilization101.pipchat.in/step/t0-containers); tier 1: [Pottery and the first kiln](https://civilization101.pipchat.in/step/t1-pottery); tier 2: [Brick and tile](https://civilization101.pipchat.in/step/t2-brick); tier 3: [Glass](https://civilization101.pipchat.in/step/t3-glass)
- [Metals](https://civilization101.pipchat.in/track/metals): tier 2: [Smelting: first metal](https://civilization101.pipchat.in/step/t2-smelt); tier 3: [Steel and heat treatment](https://civilization101.pipchat.in/step/t3-steel); tier 4: [Blast furnace and cheap iron](https://civilization101.pipchat.in/step/t4-blast); tier 5: [Electrochemistry and light metals](https://civilization101.pipchat.in/step/t5-electrochem)
- [Binders](https://civilization101.pipchat.in/track/binders): tier 2: [Lime](https://civilization101.pipchat.in/step/t2-lime); tier 3: [Cement and concrete](https://civilization101.pipchat.in/step/t3-cement)
- [Chemicals](https://civilization101.pipchat.in/track/chemicals): tier 2: [Salt](https://civilization101.pipchat.in/step/t2-salt), [Fermentation and distilling](https://civilization101.pipchat.in/step/t2-brew); tier 3: [Acids](https://civilization101.pipchat.in/step/t3-acid), [Alkalis](https://civilization101.pipchat.in/step/t3-alkali); tier 5: [Synthetic nitrogen](https://civilization101.pipchat.in/step/t5-haber), [Polymers](https://civilization101.pipchat.in/step/t5-polymers)

### Tools & Industry

You cannot make a part more accurate than the machine that made it. The sector runs from a cutting edge through woodworking and the forge to the machine tools that make interchangeable parts possible. Those parts also need standard units, from Knowledge & Education, before a factory can exist. Page: https://civilization101.pipchat.in/sector/tools

- [Hand tools](https://civilization101.pipchat.in/track/hand-tools): tier 0: [A cutting edge](https://civilization101.pipchat.in/step/t0-cut)
- [Woodworking](https://civilization101.pipchat.in/track/woodworking): tier 1: [Woodworking and the first machines](https://civilization101.pipchat.in/step/t1-woodwork)
- [Metalworking](https://civilization101.pipchat.in/track/metalworking): tier 2: [Blacksmithing](https://civilization101.pipchat.in/step/t2-smith); tier 3: [Machine tools and precision](https://civilization101.pipchat.in/step/t3-machinetools)
- [Production](https://civilization101.pipchat.in/track/production): tier 4: [The factory and interchangeable parts](https://civilization101.pipchat.in/step/t4-factory)

### Transport

Water carries loads long before roads do: boats come at level 1 and canals at level 3. Cold water kills by the **1-10-1 rule**: about 1 minute of cold shock, about 10 minutes of useful movement, and about an hour before unconsciousness. So floating and swimming come before any boat. On land, the wheel needs a smith and a road, and a cart needs about **3 m** of street to pass. In the air, kites and balloons come before gliders, and every flying machine is tested unmanned before anyone flies in it. Page: https://civilization101.pipchat.in/sector/transport

- [On water](https://civilization101.pipchat.in/track/on-water): tier 1: [Boats and safe water travel](https://civilization101.pipchat.in/step/t1-boats); tier 2: [Plank boats, oars and sail](https://civilization101.pipchat.in/step/t2-plank-boats); tier 3: [Canals and locks](https://civilization101.pipchat.in/step/t3-canals), [Seagoing sailing ships](https://civilization101.pipchat.in/step/t3-ships); tier 4: [Steam, iron hulls and the load line](https://civilization101.pipchat.in/step/t4-steamships); tier 5: [Submarines and submersibles](https://civilization101.pipchat.in/step/t5-submarines); tier 7: [Modern ships and small craft](https://civilization101.pipchat.in/step/t7-shipping)
- [On land](https://civilization101.pipchat.in/track/on-land): tier 2: [Wheel, cart and road](https://civilization101.pipchat.in/step/t2-wheel); tier 4: [Rail and bulk transport](https://civilization101.pipchat.in/step/t4-rail); tier 5: [Internal combustion and mobility](https://civilization101.pipchat.in/step/t5-engine)
- [In the air](https://civilization101.pipchat.in/track/in-air): tier 2: [Kites: lifting a line, signalling, fishing](https://civilization101.pipchat.in/step/t2-kites); tier 3: [Balloons](https://civilization101.pipchat.in/step/t3-balloons); tier 4: [Gliders and the control problem](https://civilization101.pipchat.in/step/t4-gliders); tier 5: [The powered aeroplane](https://civilization101.pipchat.in/step/t5-aeroplane); tier 6: [Jets, helicopters and air traffic control](https://civilization101.pipchat.in/step/t6-jets); tier 7: [Modern aviation and drones](https://civilization101.pipchat.in/step/t7-aviation)

### Knowledge & Education

Knowledge is lost far more often than it is gained. The sector starts with the record, marks and tallies on day one, then writing, paper and printing, which make copies cheaper than losses. Schools and arithmetic for everyone make a written record checkable. Measurement, controlled comparison and publication make it cumulative; the university, the laboratory and statistics make it outlast the people who found it, and a free press carries it to everyone. Page: https://civilization101.pipchat.in/sector/knowledge

- [Records and writing](https://civilization101.pipchat.in/track/records): tier 0: [Start the record](https://civilization101.pipchat.in/step/t0-record); tier 2: [Writing and the durable record](https://civilization101.pipchat.in/step/t2-writing); tier 3: [Paper](https://civilization101.pipchat.in/step/t3-paper), [Printing](https://civilization101.pipchat.in/step/t3-printing); tier 5: [The press, and who gets to speak](https://civilization101.pipchat.in/step/t5-press)
- [Teaching](https://civilization101.pipchat.in/track/teaching): tier 2: [Teach the next generation](https://civilization101.pipchat.in/step/t2-school), [Arithmetic for everyone](https://civilization101.pipchat.in/step/t2-numeracy); tier 4: [Knowledge held by an institution](https://civilization101.pipchat.in/step/t4-university)
- [Science and measurement](https://civilization101.pipchat.in/track/science): tier 3: [Instruments and measurement](https://civilization101.pipchat.in/step/t3-instruments), [One metre, one kilogram, everywhere](https://civilization101.pipchat.in/step/t3-units), [Controlled comparison and the negative result](https://civilization101.pipchat.in/step/t3-method); tier 4: [Priority by publication](https://civilization101.pipchat.in/step/t4-journal), [The laboratory as an institution](https://civilization101.pipchat.in/step/t4-lab); tier 5: [Knowing whether a result is real](https://civilization101.pipchat.in/step/t5-statistics)

### Communication & Computing

Signals over distance begin with the telegraph at level 4, which needs batteries, acids and machine-made wire, and radio follows at level 5. Semiconductors are where the ladder stops being climbable by a determined group: the physics can be taught in an afternoon, but the purity and cleanliness they demand cannot be met by a small one. Page: https://civilization101.pipchat.in/sector/comms

- [Signals](https://civilization101.pipchat.in/track/signals): tier 4: [Telegraph](https://civilization101.pipchat.in/step/t4-telegraph); tier 5: [Radio](https://civilization101.pipchat.in/step/t5-radio)
- [Electronics and computing](https://civilization101.pipchat.in/track/computing): tier 6: [Electronics: amplification and switching](https://civilization101.pipchat.in/step/t6-electronics), [Semiconductors](https://civilization101.pipchat.in/step/t6-semiconductor), [Computing](https://civilization101.pipchat.in/step/t6-computing), [Networks](https://civilization101.pipchat.in/step/t6-network)

### Economy & Trade

Debt precedes coin by millennia: the first financial instrument is a tally of who owes what. Double entry makes an enterprise checkable by a stranger, and credit moves purchasing power across time, which the factory and the railway need and otherwise have no way to fund. The chain runs from the tally through the verified weight, the coin tested in public, the company that pools capital under disclosure, to a central bank that holds the price level. Page: https://civilization101.pipchat.in/sector/economy

- [Money, credit and capital](https://civilization101.pipchat.in/track/money): tier 1: [The debt record](https://civilization101.pipchat.in/step/t1-tally); tier 2: [Standard weight](https://civilization101.pipchat.in/step/t2-weights); tier 3: [Double entry and the auditable enterprise](https://civilization101.pipchat.in/step/t3-ledger), [Fungible token and the mint](https://civilization101.pipchat.in/step/t3-coin); tier 4: [Credit, interest and the bank](https://civilization101.pipchat.in/step/t4-credit), [Pooled capital and limited liability](https://civilization101.pipchat.in/step/t4-company); tier 5: [Reserves and the price level](https://civilization101.pipchat.in/step/t5-monetary)

### Society, Law & Governance

Decide how you decide before anything else is contested. The chains here run from the group's first rule to boundary and tenure, published law, contract, the registers and a constitution that binds the rulers; and from the first public good through the census, the health authority and a civil service to the front counter and independent audit. The health authority is on the record the largest life-expectancy gain of any institution, almost all of it before antibiotics. The institutions guide lists every public institution in founding order, with the safeguards that keep each honest. Page: https://civilization101.pipchat.in/sector/society

- [Deciding together](https://civilization101.pipchat.in/track/deciding): tier 0: [Decide how you decide](https://civilization101.pipchat.in/step/t0-org); tier 7: [Institutions that outlive people](https://civilization101.pipchat.in/step/t7-institutions), [Decide what not to rebuild](https://civilization101.pipchat.in/step/t7-choose)
- [Land and law](https://civilization101.pipchat.in/track/land-law): tier 1: [Boundary and tenure](https://civilization101.pipchat.in/step/t1-property); tier 2: [Published rule and the court](https://civilization101.pipchat.in/step/t2-writtenlaw); tier 3: [The enforceable promise](https://civilization101.pipchat.in/step/t3-contract); tier 4: [The register: land, birth, company](https://civilization101.pipchat.in/step/t4-registry); tier 5: [Constraint on the ruler](https://civilization101.pipchat.in/step/t5-rights)
- [Public works and administration](https://civilization101.pipchat.in/track/public-works): tier 1: [The first public good](https://civilization101.pipchat.in/step/t1-commonworks); tier 2: [Count before you administer](https://civilization101.pipchat.in/step/t2-census); tier 3: [The health authority](https://civilization101.pipchat.in/step/t3-publichealth); tier 4: [Standing departments and a civil service](https://civilization101.pipchat.in/step/t4-service); tier 5: [Citizen services and the front counter](https://civilization101.pipchat.in/step/t5-citizen); tier 6: [Audit, statistics and the published number](https://civilization101.pipchat.in/step/t6-accountability)
- [Security](https://civilization101.pipchat.in/track/security): tier 1: [Keep watch and defend the settlement](https://civilization101.pipchat.in/step/t1-watch)

## The Ladder

Each step lists its prerequisites, inputs, minimum people and effort, a numbered procedure with a check per entry, failure modes, a verification test and cited sources. A step never depends on a later tier. Page: https://civilization101.pipchat.in/ladder

### Tier 0 — Triage (Any survivor, day one; Day 0 – Day 90; population 1+)

Stop dying. Nothing else on this site matters until this tier is closed. Full text: https://civilization101.pipchat.in/data/tiers/t0.json

- [Find and hold water](https://civilization101.pipchat.in/step/t0-water-find): Secure a source you can reach twice a day, forever, without a fight.
- [Make water safe](https://civilization101.pipchat.in/step/t0-water-safe): Kill what is in the water before it kills you.
- [Fire, and keeping it](https://civilization101.pipchat.in/step/t0-fire): Make fire from nothing, then never make it from nothing again.
- [Shelter and body heat](https://civilization101.pipchat.in/step/t0-shelter): Get off the ground, out of the wind, and dry.
- [Separate waste from water](https://civilization101.pipchat.in/step/t0-latrine): Break the faecal–oral route on day one, before habits form.
- [Lay out the camp](https://civilization101.pipchat.in/step/t0-camp): Place shelters, water, latrines and paths on the first day so that fire, flood and faecal disease cannot sweep the camp.
- [A cutting edge](https://civilization101.pipchat.in/step/t0-cut): Make something that cuts, and something that can make another one.
- [Cordage](https://civilization101.pipchat.in/step/t0-cord): Turn plant fibre into string, then string into rope.
- [Forage, trap, fish](https://civilization101.pipchat.in/step/t0-food): Take calories out of the landscape while you wait for agriculture to start paying.
- [Containers](https://civilization101.pipchat.in/step/t0-containers): Carry, store and cook — before you have pottery.
- [Wound care and first aid](https://civilization101.pipchat.in/step/t0-firstaid): Stop bleeding, prevent infection, and set what is broken.
- [Secure seed and breeding stock](https://civilization101.pipchat.in/step/t0-seed): Protect the genetic capital that everything above this tier is built on.
- [Decide how you decide](https://civilization101.pipchat.in/step/t0-org): Agree the rule for making decisions, before you need to make a hard one.
- [Start the record](https://civilization101.pipchat.in/step/t0-record): Begin, on day one, the deliberate transfer of what you know to people who will outlive you.

### Tier 1 — Foothold (Neolithic; Month 3 – Year 3; population 12+)

Convert from taking calories out of the landscape to putting them in. Stop moving. Full text: https://civilization101.pipchat.in/data/tiers/t1.json

- [Read the year](https://civilization101.pipchat.in/step/t1-calendar): Know when to plant, without being told.
- [Open ground and hold fertility](https://civilization101.pipchat.in/step/t1-clear): Turn wild land into a field that does not lose its fertility in five years.
- [Plant staples](https://civilization101.pipchat.in/step/t1-staples): Grow enough storable calories to stop foraging.
- [Preserve the harvest](https://civilization101.pipchat.in/step/t1-preserve): Still be eating in March what you grew in August.
- [Prevent deficiency disease](https://civilization101.pipchat.in/step/t1-nutrition): Keep a farming group from sickening on its own staple.
- [Teeth: prevent decay, and catch the abscess that spreads](https://civilization101.pipchat.in/step/t1-teeth): Keep teeth through a starch-heavy diet, and recognise the dental infection that kills.
- [Livestock](https://civilization101.pipchat.in/step/t1-animals): Convert grass you cannot eat into food, fibre, fertiliser and power.
- [Permanent shelter](https://civilization101.pipchat.in/step/t1-shelter): Build something that lasts thirty years, from what is under your feet.
- [Choose the ground](https://civilization101.pipchat.in/step/t1-site): Settle where water lasts the dry season, floods cannot reach the floors, the ground drains and the wind carries smoke away.
- [Plan the house: sun, air, smoke and damp](https://civilization101.pipchat.in/step/t1-dwelling): Before the first footing is dug, a plan drawn to scale fixes where the fire and its smoke go, how many people sleep in each room, the wall weight for the climate, the house's turn to the winter sun, the overhang for its latitude, the openings for a through-draught, the floor height, and where the animals and the latrine stand.
- [Pottery and the first kiln](https://civilization101.pipchat.in/step/t1-pottery): Make a fire-proof, waterproof, permanent container — and learn to control temperature.
- [Fibre, thread and cloth](https://civilization101.pipchat.in/step/t1-textiles): Make cloth, so you are not dependent on hides.
- [Tanning and leather](https://civilization101.pipchat.in/step/t1-tanning): Turn raw hide into a material that does not rot.
- [Soap](https://civilization101.pipchat.in/step/t1-soap): Make the cheapest life-saving technology ever invented.
- [Childbirth and infant survival](https://civilization101.pipchat.in/step/t1-midwifery): Stop losing mothers and infants to preventable causes.
- [Woodworking and the first machines](https://civilization101.pipchat.in/step/t1-woodwork): Make things accurately from wood, including the machines that will later work metal.
- [Boats and safe water travel](https://civilization101.pipchat.in/step/t1-boats): Cross and work water without drowning — raft, dugout and paddle.
- [The debt record](https://civilization101.pipchat.in/step/t1-tally): Write down who owes what, before anyone mints anything.
- [Boundary and tenure](https://civilization101.pipchat.in/step/t1-property): Establish who holds which ground, in a form that outlives the argument.
- [The first public good](https://civilization101.pipchat.in/step/t1-commonworks): Build the thing everyone needs and nobody owns — and settle who pays for it.
- [Keep watch and defend the settlement](https://civilization101.pipchat.in/step/t1-watch): Make the settlement hard to surprise, raid or burn — without starting a feud.

### Tier 2 — Forge (Bronze and Iron Age; Year 2 – Year 12; population 60+)

Get above 1,100 °C and keep a written record. These two moves open more doors than everything below them combined. Full text: https://civilization101.pipchat.in/data/tiers/t2.json

- [Charcoal](https://civilization101.pipchat.in/step/t2-charcoal): Make a fuel that burns hot enough to melt metal.
- [Smelting: first metal](https://civilization101.pipchat.in/step/t2-smelt): Extract metal from rock.
- [Blacksmithing](https://civilization101.pipchat.in/step/t2-smith): Shape metal into tools — including the tools for shaping metal.
- [Lime](https://civilization101.pipchat.in/step/t2-lime): Burn limestone and unlock mortar, plaster, flux, and disinfection.
- [Brick and tile](https://civilization101.pipchat.in/step/t2-brick): Make a standard, repeatable building unit — and something that will line a furnace.
- [Masonry house and chimney](https://civilization101.pipchat.in/step/t2-masonry): Walls of fired brick or stone in lime mortar, a roof that does not burn, and a chimney that takes every trace of smoke out of the house.
- [Barn and byre](https://civilization101.pipchat.in/step/t2-barn): House the herd and its winter fodder so that the bedding stays dry, the air stays below the ammonia limit, the hay cannot burn the byre or the house, and nothing from either reaches the well or the people.
- [Salt](https://civilization101.pipchat.in/step/t2-salt): Secure a mineral you cannot live without and cannot grow.
- [Writing and the durable record](https://civilization101.pipchat.in/step/t2-writing): Move knowledge out of heads and onto something that outlives them.
- [Teach the next generation](https://civilization101.pipchat.in/step/t2-school): Build the institution that makes knowledge survive a death.
- [Wheel, cart and road](https://civilization101.pipchat.in/step/t2-wheel): Move heavy things further than you can carry them.
- [Plank boats, oars and sail](https://civilization101.pipchat.in/step/t2-plank-boats): Build boats of planks that carry a family and its goods, row them with oars sized by rule, and add a sail only to a boat that passes the stability test.
- [Kites: lifting a line, signalling, fishing](https://civilization101.pipchat.in/step/t2-kites): Fly kites that carry a line across a river or a gorge, lift an aerial or a signal, and show how a surface held at an angle to the wind makes lift.
- [Irrigation and water control](https://civilization101.pipchat.in/step/t2-irrigate): Put water where the crop is, when the crop needs it.
- [Fish ponds: build, fertilise and harvest an earthen pond](https://civilization101.pipchat.in/step/t2-fishpond): Grow a crop of fish in a fenced, drainable earthen pond that holds its water, keeps the dawn oxygen above the species' minimum, and is drained, harvested and dried each cycle.
- [Fermentation and distilling](https://civilization101.pipchat.in/step/t2-brew): Put microbes to work — your first biotechnology.
- [Plant medicine and the pharmacy](https://civilization101.pipchat.in/step/t2-medicine): Build a small, honest pharmacopoeia from what grows locally.
- [Arithmetic for everyone](https://civilization101.pipchat.in/step/t2-numeracy): Make counting, measuring and reckoning ordinary rather than specialist.
- [Published rule and the court](https://civilization101.pipchat.in/step/t2-writtenlaw): Put the rules where everyone can read them, and separate judging from ruling.
- [Standard weight](https://civilization101.pipchat.in/step/t2-weights): Give every market a balance whose readings can be checked and a set of reference weights within published tolerances, held to a master by an office that verifies, stamps and re-inspects them.
- [Count before you administer](https://civilization101.pipchat.in/step/t2-census): Count every person and dwelling as at one date, so that decisions about food, water, schools and shares start from a number rather than a guess.
- [Plot, street and block](https://civilization101.pipchat.in/step/t2-plot): Lay out the settlement before it lays itself out.

### Tier 3 — Mill (Medieval to early modern; Year 8 – Year 30; population 300+)

Put something other than muscle to work, and start making machines that make machines. Full text: https://civilization101.pipchat.in/data/tiers/t3.json

- [Water power](https://civilization101.pipchat.in/step/t3-waterpower): Get a source of continuous power that is not a muscle.
- [Wind power](https://civilization101.pipchat.in/step/t3-windpower): Get continuous power where there is no falling water — which is most places.
- [Canals and locks](https://civilization101.pipchat.in/step/t3-canals): Carry bulk goods by water where no river goes, and lift boats over hills.
- [Seagoing sailing ships](https://civilization101.pipchat.in/step/t3-ships): Build and sail decked ships that cross open sea with cargo and crew, without capsizing, sinking or losing the crew to scurvy.
- [Balloons](https://civilization101.pipchat.in/step/t3-balloons): Lift a load with heated air or a light gas, tether it for observation or signals, and know exactly how much it can carry and what makes it burn.
- [Machine tools and precision](https://civilization101.pipchat.in/step/t3-machinetools): Build machines that make machines — and break the accuracy ceiling.
- [Steel and heat treatment](https://civilization101.pipchat.in/step/t3-steel): Make metal hard enough to cut other metal.
- [Cement and concrete](https://civilization101.pipchat.in/step/t3-cement): Make artificial stone you can pour into any shape.
- [Glass](https://civilization101.pipchat.in/step/t3-glass): Make a transparent, chemically inert, formable solid.
- [Cold frames, hotbeds and the glasshouse](https://civilization101.pipchat.in/step/t3-glasshouse): Raise transplants before the last frost and keep tender crops growing after the first, under glass warmed by the sun, by rotting manure and by a wall that holds the day's heat.
- [The four-course rotation, field drains and the seed drill](https://civilization101.pipchat.in/step/t3-rotation): Run the fields as one system: a rotation whose fodder crops feed the stock and whose manure feeds the grain, wet land underdrained so it can be worked and sown, and grain drilled in rows at a known rate and depth so it can be counted and hoed.
- [Framed and glazed building](https://civilization101.pipchat.in/step/t3-frame): Frame a building in timber on a masonry plinth, brace it so it cannot rack, glaze its windows, and keep it dry, warm and ventilated.
- [Acids](https://civilization101.pipchat.in/step/t3-acid): Make sulphuric acid, and with it most of industrial chemistry.
- [Alkalis](https://civilization101.pipchat.in/step/t3-alkali): Make soda ash and caustic soda at scale.
- [Batteries: from the voltaic pile to the lead-acid cell](https://civilization101.pipchat.in/step/t3-battery): Make a steady electric current from chemicals — for the telegraph, plating and electrolysis — before there is any generator.
- [Paper](https://civilization101.pipchat.in/step/t3-paper): Make a cheap, plentiful writing surface.
- [Printing](https://civilization101.pipchat.in/step/t3-printing): Make copies faster than people can write them.
- [Germ theory and antisepsis](https://civilization101.pipchat.in/step/t3-germ): Establish that disease is caused by organisms — and act on it.
- [Make chlorine disinfectant](https://civilization101.pipchat.in/step/t3-chlorine): Make sodium hypochlorite from salt, water and direct current, measure its strength, and dose drinking water so that 0.2–0.5 mg/L of free chlorine remains 30 minutes later.
- [Instruments and measurement](https://civilization101.pipchat.in/step/t3-instruments): Turn observation into numbers.
- [One metre, one kilogram, everywhere](https://civilization101.pipchat.in/step/t3-units): Fix the units, hold the standards, and make every measurement comparable to every other.
- [Controlled comparison and the negative result](https://civilization101.pipchat.in/step/t3-method): Establish how you decide whether something is actually true.
- [Double entry and the auditable enterprise](https://civilization101.pipchat.in/step/t3-ledger): Keep accounts a stranger can check.
- [Fungible token and the mint](https://civilization101.pipchat.in/step/t3-coin): Strike coins of a weight, fineness and size fixed in law, at one mint working under seal, and prove every year, in public, that they meet the standard.
- [The enforceable promise](https://civilization101.pipchat.in/step/t3-contract): Make a promise between strangers as reliable as one between kin, by writing it down and having a court enforce it quickly and cheaply.
- [The health authority](https://civilization101.pipchat.in/step/t3-publichealth): Give someone the standing, the information and the power to act on disease before it spreads.
- [Fire separation and the building code](https://civilization101.pipchat.in/step/t3-fire): Write and enforce a building code that stops a fire in one building from reaching the next, gets everyone out of the building it starts in, and puts enough water within reach of every building.

### Tier 4 — Engine (Industrial revolution; Year 20 – Year 60; population 2,000+)

Burn stored sunlight instead of current sunlight. Break the land-area limit on energy. Full text: https://civilization101.pipchat.in/data/tiers/t4.json

- [Coal and coke](https://civilization101.pipchat.in/step/t4-coal): Break the land-area limit on energy.
- [Blast furnace and cheap iron](https://civilization101.pipchat.in/step/t4-blast): Make iron by the tonne instead of by the kilogram.
- [The steam engine](https://civilization101.pipchat.in/step/t4-steam): Turn heat into motion, anywhere you want it.
- [The factory and interchangeable parts](https://civilization101.pipchat.in/step/t4-factory): Make many identical things, and make them repairable.
- [Rail and bulk transport](https://civilization101.pipchat.in/step/t4-rail): Move mass cheaply overland.
- [Steam, iron hulls and the load line](https://civilization101.pipchat.in/step/t4-steamships): Drive ships by steam against wind and current, build them of iron and steel, and stop them being overloaded or blown up by their own boilers.
- [Gliders and the control problem](https://civilization101.pipchat.in/step/t4-gliders): Design wings from measured data, make a glider stable and controllable in all three axes, and prove it with models, a wind tunnel and unmanned tests before anyone rides it.
- [City water and sewerage](https://civilization101.pipchat.in/step/t4-sanitation): Keep a dense settlement from poisoning itself.
- [Refrigeration and the cold chain](https://civilization101.pipchat.in/step/t4-cold): Hold food and medicine at a set cold temperature, all year, anywhere.
- [Telegraph](https://civilization101.pipchat.in/step/t4-telegraph): Make information travel faster than people.
- [Anaesthesia and real surgery](https://civilization101.pipchat.in/step/t4-anaesthesia): Make surgery survivable and therefore worth attempting.
- [Priority by publication](https://civilization101.pipchat.in/step/t4-journal): Make disclosing what you know the self-interested move.
- [Knowledge held by an institution](https://civilization101.pipchat.in/step/t4-university): Found universities that hold knowledge beyond any one teacher's lifetime: self-governing, free to teach and publish, examining to standards checked from outside, and reviewed by an independent agency.
- [The laboratory as an institution](https://civilization101.pipchat.in/step/t4-lab): Run laboratories whose results can be trusted and reconstructed after the investigator has gone: written procedures, calibrated instruments, raw data recorded and archived, quality checked by people independent of the work, hazards controlled by assessment, and competence proven to an outside body.
- [Credit, interest and the bank](https://civilization101.pipchat.in/step/t4-credit): Move purchasing power across time, and survive the moment everyone wants it back at once.
- [Pooled capital and limited liability](https://civilization101.pipchat.in/step/t4-company): Let anyone form a company by registering it, let thousands of people invest in it while risking only what they put in, and pay for that protection with a public register, audited accounts and a board bound by duties to the shareholders.
- [The register: land, birth, company](https://civilization101.pipchat.in/step/t4-registry): Keep one public, durable record of who owns which land, who was born and who died, and which companies exist and who controls them.
- [Standing departments and a civil service](https://civilization101.pipchat.in/step/t4-service): Run each public function through a department with one written mandate, staffed by officials hired on merit who serve whoever is lawfully in charge.
- [Zoning: separation distances, wind, river and flood](https://civilization101.pipchat.in/step/t4-zoning): Every parcel has a published zone, every odour, dust or major-hazard works stands at least its separation distance from homes and downwind and downstream of them, no home stands in the functional floodplain, and no hazardous-substance store stands in the 1 % flood zone.
- [Iron-framed and multi-storey building](https://civilization101.pipchat.in/step/t4-ironframe): Raise buildings of three storeys and more on iron columns, iron or steel beams and brick walls, with every load traced to the ground, cast iron used only where it is squeezed, walls no more slender than the code allows, and the iron protected from fire.

### Tier 5 — Current (Second industrial revolution; Year 45 – Year 110; population 20,000+)

Move energy without moving matter, and break the nitrogen limit on food. Full text: https://civilization101.pipchat.in/data/tiers/t5.json

- [The generator](https://civilization101.pipchat.in/step/t5-generator): Convert motion into electricity, and electricity back into motion.
- [Electrochemistry and light metals](https://civilization101.pipchat.in/step/t5-electrochem): Use electricity to do chemistry that heat cannot.
- [Petroleum and refining](https://civilization101.pipchat.in/step/t5-oil): Get a liquid fuel — dense, portable and pourable.
- [Internal combustion and mobility](https://civilization101.pipchat.in/step/t5-engine): Put a compact engine in a vehicle.
- [The powered aeroplane](https://civilization101.pipchat.in/step/t5-aeroplane): Add an engine and propellers to a controllable airframe, keep weight and balance inside limits, and fly only proven, inspected designs with trained pilots.
- [Submarines and submersibles](https://civilization101.pipchat.in/step/t5-submarines): Take a hull under water and bring it back: trim it with ballast, build it for the pressure at its depth, and dive only a classed, tested design with a trained crew.
- [Synthetic nitrogen](https://civilization101.pipchat.in/step/t5-haber): Pull fertiliser out of the air.
- [Antibiotics and vaccines](https://civilization101.pipchat.in/step/t5-antibiotics): Make infection survivable.
- [Radio](https://civilization101.pipchat.in/step/t5-radio): Communicate with no wire between you.
- [Polymers](https://civilization101.pipchat.in/step/t5-polymers): Make materials with properties no natural material has.
- [The modern greenhouse: film, glass and climate control](https://civilization101.pipchat.in/step/t5-greenhouse): Hold the crop's temperature, humidity, light and carbon dioxide within range all year, at a heating and cooling cost worked out before the house is built.
- [Soilless growing: hydroponics and substrates](https://civilization101.pipchat.in/step/t5-hydroponics): Grow greenhouse crops with their roots in a flowing nutrient solution or an inert substrate, with the solution's strength, acidity and oxygen measured every day and held in the crop's range.
- [Steel frame and reinforced concrete](https://civilization101.pipchat.in/step/t5-concrete): Build frames of reinforced concrete or steel, or confined masonry, that carry their loads with the steel where the tension is, the concrete mix, cover and curing the exposure needs, and the earthquake detailing the region needs, each stage inspected before it is hidden.
- [Constraint on the ruler](https://civilization101.pipchat.in/step/t5-rights): Put the rules that bind the rule-makers into a supreme, published law that they cannot change alone and that courts enforce against them.
- [Citizen services and the front counter](https://civilization101.pipchat.in/step/t5-citizen): Give every person one place to get any public service, with published requirements, fee and deadline, and someone independent to complain to.
- [Reserves and the price level](https://civilization101.pipchat.in/step/t5-monetary): Measure the price level every month, give an independent central bank a published inflation target and the tools to meet it, and make banks safe enough that a run on one does not become a run on all.
- [Knowing whether a result is real](https://civilization101.pipchat.in/step/t5-statistics): Draw samples at random, state the uncertainty of every estimate, fix the plan before the data arrive, read significance tests for what they are, and believe a finding only when it has been replicated.
- [The press, and who gets to speak](https://civilization101.pipchat.in/step/t5-press): Let anyone publish without a licence, protect what they publish from punishment for criticising the powerful, keep the media many and independent, protect journalists and their sources, and hold the press to correcting its own errors.
- [Drip and sprinkler irrigation](https://civilization101.pipchat.in/step/t5-drip): Put each crop's water at its roots through pipes, in the amount the crop uses, when the soil says it needs it, with every emitter on a line delivering within 10 % of the others.
- [Plan the city before it grows](https://civilization101.pipchat.in/step/t5-city): Before the city reaches its fringe, reserve the land it will need for 20–30 years, secure an arterial grid about 1 km apart with its rights-of-way, lay a street hierarchy and utility corridors inside it, and publish the plan.

### Tier 6 — Logic (Electronic and computing; Year 90 – Year 170; population 500,000+)

Make matter that computes. Stop paying for every copy of a thing you know. Full text: https://civilization101.pipchat.in/data/tiers/t6.json

- [Electronics: amplification and switching](https://civilization101.pipchat.in/step/t6-electronics): Control a large current with a small one.
- [Semiconductors](https://civilization101.pipchat.in/step/t6-semiconductor): Make matter with controllable conductivity — the hardest thing on this site.
- [Computing](https://civilization101.pipchat.in/step/t6-computing): Automate reasoning that is mechanical.
- [Networks](https://civilization101.pipchat.in/step/t6-network): Let every store of knowledge reach every person.
- [Jets, helicopters and air traffic control](https://civilization101.pipchat.in/step/t6-jets): Understand the gas turbine, the pressurised cabin, the helicopter and the air traffic system that let aircraft fly high, fast and safely in crowded skies.
- [Audit, statistics and the published number](https://civilization101.pipchat.in/step/t6-accountability): Give the public numbers it can trust about what government spends and achieves, produced and checked by offices the government cannot instruct.
- [High-yield varieties, and the Green Revolution's bill](https://civilization101.pipchat.in/step/t6-greenrev): Breed and supply short-strawed, high-yielding cereal varieties with the fertilizer and water they need, and pay their known costs up front: metered groundwater, no highly hazardous pesticides, a gene bank for the varieties they replace, and nutrients bred back into the staples.

### Tier 7 — Frontier (Contemporary and beyond; Year 150+; population Millions)

Reach the point you started from — then decide, deliberately, what to do differently. Full text: https://civilization101.pipchat.in/data/tiers/t7.json

- [Energy without the carbon bill](https://civilization101.pipchat.in/step/t7-energy): Reach an industrial energy supply that does not have to be paid for twice.
- [Modern ships and small craft](https://civilization101.pipchat.in/step/t7-shipping): Move the world's goods by sea safely and with falling emissions, and build and equip small boats to the standards that keep their crews alive.
- [Modern aviation and drones](https://civilization101.pipchat.in/step/t7-aviation): Fly people and goods with the safety of today's airlines, fly drones within the rules, and cut aviation's emissions.
- [Biology as engineering](https://civilization101.pipchat.in/step/t7-bio): Read and write the code that living things run on.
- [Institutions that outlive people](https://civilization101.pipchat.in/step/t7-institutions): Build the machinery that makes the other steps hold.
- [Decide what not to rebuild](https://civilization101.pipchat.in/step/t7-choose): Use the one genuine advantage a second attempt has: hindsight.
- [Vertical farms and controlled environments](https://civilization101.pipchat.in/step/t7-cea): Grow leafy greens, herbs and transplants on stacked tiers under electric light, with the electricity per kilogram worked out before building, and the room held safe for the people working in it.
- [Sustainable intensification](https://civilization101.pipchat.in/step/t7-farming): Raise yields on the land already farmed while cutting the nitrogen, water, methane and soil each tonne costs, and stop losing the harvest after it is grown, each change measured on the farm.
- [The compact, connected, resilient city](https://civilization101.pipchat.in/step/t7-city): Build and renew neighbourhoods to UN-Habitat's five principles, with public transport and open space within a short walk of everyone, and plan, measure and report disaster risk against the Sendai Framework's targets.

## Builds

Dimensioned blueprints, bills of materials, tolerances, construction procedures, failure modes and verification tests for the things the ladder tells you to make. Page: https://civilization101.pipchat.in/builds

- [Raised granary](https://civilization101.pipchat.in/build/granary) (tier 1, Shelter › Storage and farm buildings): Keep a year of grain dry, cool and away from rodents — the single highest-return building on the site. Data: https://civilization101.pipchat.in/data/builds/granary.json
- [Root cellar](https://civilization101.pipchat.in/build/root-cellar) (tier 1, Shelter › Storage and farm buildings): Cold, damp and dark, without power — how a harvest survives to the following spring. Data: https://civilization101.pipchat.in/data/builds/root-cellar.json
- [One-room earth house](https://civilization101.pipchat.in/build/earth-house) (tier 1, Shelter › Dwellings): Sun-dried earth blocks on a stone plinth under a thatched roof, 4.0 × 3.6 m inside — the worked example for the building guide, from pegs in the ground to the first winter. Data: https://civilization101.pipchat.in/data/builds/earth-house.json
- [Fireplace and chimney](https://civilization101.pipchat.in/build/fireplace-chimney) (tier 2, Shelter › Dwellings): A fireplace that throws its heat into the room and a lined flue that takes every trace of smoke out of the house: the part of a house most likely to burn it down or poison the people in it. Data: https://civilization101.pipchat.in/data/builds/fireplace-chimney.json
- [Log house](https://civilization101.pipchat.in/build/log-house) (tier 1, Shelter › Dwellings): Where straight timber grows and there is no clay or stone, the fastest permanent walls an axe can raise: structure, enclosure and insulation in one piece. Data: https://civilization101.pipchat.in/data/builds/log-house.json
- [Twin-vault composting latrine](https://civilization101.pipchat.in/build/composting-latrine) (tier 1, Water › Sanitation): Break the faecal–oral route and return the nutrients — the highest lives-saved-per-effort structure a settlement can build. Data: https://civilization101.pipchat.in/data/builds/composting-latrine.json
- [Slow sand filter](https://civilization101.pipchat.in/build/slow-sand-filter) (tier 1, Water › Make water safe): Clean drinking water with no chemicals, no power and no moving parts — the highest lives-saved-per-effort structure on this site. Data: https://civilization101.pipchat.in/data/builds/slow-sand-filter.json
- [Funnel basket fish trap](https://civilization101.pipchat.in/build/fish-trap) (tier 0, Food › Wild food): A woven basket that fishes all night while you sleep — the highest return-per-hour food gear in tier 0. Data: https://civilization101.pipchat.in/data/builds/fish-trap.json
- [Gill net](https://civilization101.pipchat.in/build/gill-net) (tier 1, Food › Wild food): A wall of near-invisible mesh that fishes a whole channel while you do something else. Data: https://civilization101.pipchat.in/data/builds/gill-net.json
- [Spring-pole lathe](https://civilization101.pipchat.in/build/pole-lathe) (tier 1, Tools › Woodworking): The first machine tool — a sapling, a cord and a treadle, and the direct ancestor of everything in tier 3. Data: https://civilization101.pipchat.in/data/builds/pole-lathe.json
- [Updraught kiln](https://civilization101.pipchat.in/build/updraught-kiln) (tier 1, Materials › Ceramics and glass): The first machine that holds a temperature — pottery, brick and tile, and the training ground for every furnace above it. Data: https://civilization101.pipchat.in/data/builds/updraught-kiln.json
- [Earth charcoal clamp](https://civilization101.pipchat.in/build/charcoal-clamp) (tier 2, Energy › Fire and fuel): Turn wood into the fuel that reaches smelting heat — no kiln, no metal, just a stack, a cover and a week of attention. Data: https://civilization101.pipchat.in/data/builds/charcoal-clamp.json
- [Double-chamber bellows](https://civilization101.pipchat.in/build/bellows) (tier 2, Tools › Metalworking): Continuous forced air — the component that decides whether you get metal or roasted rock. Data: https://civilization101.pipchat.in/data/builds/bellows.json
- [Bloomery furnace](https://civilization101.pipchat.in/build/bloomery) (tier 2, Materials › Metals): A clay shaft that turns rock into iron — the first machine that makes every other machine possible. Data: https://civilization101.pipchat.in/data/builds/bloomery.json
- [Blacksmith's forge](https://civilization101.pipchat.in/build/forge) (tier 2, Tools › Metalworking): A controlled hot spot you can hold a bar in — the hearth every other trade's tools come out of. Data: https://civilization101.pipchat.in/data/builds/forge.json
- [Continuous draw lime kiln](https://civilization101.pipchat.in/build/lime-kiln) (tier 2, Materials › Binders): Burn limestone into quicklime — mortar, plaster, whitewash, flux, tannery liquor and soil correction, from one shaft. Data: https://civilization101.pipchat.in/data/builds/lime-kiln.json
- [Overshot water wheel](https://civilization101.pipchat.in/build/overshot-wheel) (tier 3, Energy › Mechanical power): A few kilowatts, day and night, without eating — the first energy surplus large enough to support full-time specialists. Data: https://civilization101.pipchat.in/data/builds/overshot-wheel.json
- [Post mill](https://civilization101.pipchat.in/build/post-mill) (tier 3, Energy › Mechanical power): A whole building balanced on one oak post so it can be turned to face the wind — the first machine that let a settlement mill grain where there was no falling water. Data: https://civilization101.pipchat.in/data/builds/post-mill.json
- [Bead microscope](https://civilization101.pipchat.in/build/bead-microscope) (tier 3, Knowledge › Science and measurement): A glass bead the size of a pinhead magnifies 150–350 times: enough to see yeast, blood cells and the larger bacteria that cause disease. Data: https://civilization101.pipchat.in/data/builds/bead-microscope.json
- [Refracting telescope](https://civilization101.pipchat.in/build/refracting-telescope) (tier 3, Knowledge › Science and measurement): Two lenses in a tube: a 1-metre objective and a 25 mm eyepiece give 40×, enough to see Jupiter's moons and the phases of Venus. Data: https://civilization101.pipchat.in/data/builds/refracting-telescope.json
- [Set out a block](https://civilization101.pipchat.in/build/set-out-block) (tier 2, Settlements › Settlement and planning): Put the plan on the ground with cord, pegs and a triangle: square corners, straight lines and levels anyone can check again. Data: https://civilization101.pipchat.in/data/builds/set-out-block.json
- [Log raft](https://civilization101.pipchat.in/build/log-raft) (tier 1, Transport › On water): Eight dry logs, six cross-poles and cord: a raft that carries 400 kg across or down calm water, rated by sum and proved by a load test. Data: https://civilization101.pipchat.in/data/builds/log-raft.json
- [Dugout canoe with outrigger](https://civilization101.pipchat.in/build/dugout-canoe) (tier 1, Transport › On water): One sound log, fire and an adze: a two-person canoe with walls 2.5 cm thick, and an outrigger float that keeps it upright on open water. Data: https://civilization101.pipchat.in/data/builds/dugout-canoe.json
- [Coracle](https://civilization101.pipchat.in/build/coracle) (tier 1, Transport › On water): A one-person boat you carry on your back: a woven frame of split laths, a hide or cloth skin, and pitch, built in about two days. Data: https://civilization101.pipchat.in/data/builds/coracle.json
- [Flat-bottomed plank boat](https://civilization101.pipchat.in/build/flat-bottomed-boat) (tier 2, Transport › On water): FAO's 4.9 m flat-bottomed boat: straight planks, three frames, a bottom planked across and nailed to a thick lowest plank. The simplest planked boat there is, for four people on sheltered water. Data: https://civilization101.pipchat.in/data/builds/flat-bottomed-boat.json
- [Line-carrying kite](https://civilization101.pipchat.in/build/line-kite) (tier 2, Transport › In the air): A 1.5 m Eddy kite of spruce and cloth, with a bridle set by rule: steady in light wind, strong enough to carry a line across a river or a gorge. Data: https://civilization101.pipchat.in/data/builds/line-kite.json
- [Tethered model hot-air balloon](https://civilization101.pipchat.in/build/tethered-balloon) (tier 3, Transport › In the air): Twelve tissue-paper gores make a 1.5 m balloon that lifts about 250 g over a ground fire and flies on a tether: the Montgolfiers' principle, measured, with no flame in the air. Data: https://civilization101.pipchat.in/data/builds/tethered-balloon.json
- [Model glider](https://civilization101.pipchat.in/build/model-glider) (tier 4, Transport › In the air): A 60 cm hand-launched glider of thin wood, balanced and trimmed by test: the Wrights' order of work in an afternoon, and the stability every aircraft depends on. Data: https://civilization101.pipchat.in/data/builds/model-glider.json
- [Wind tunnel](https://civilization101.pipchat.in/build/wind-tunnel) (tier 4, Transport › In the air): A 41 cm square test section as long as the Wrights' box, a fan that draws air through a honeycomb, and two balances you calibrate yourself: measure a wing before you build it. Data: https://civilization101.pipchat.in/data/builds/wind-tunnel.json
- [Cold frame and manure hotbed](https://civilization101.pipchat.in/build/cold-frame-hotbed) (tier 3, Food › Protected growing): A glazed box that starts seedlings weeks early, and the same box over a pit of rotting manure that warms the soil from below. Data: https://civilization101.pipchat.in/data/builds/cold-frame-hotbed.json
- [High tunnel (hoop house)](https://civilization101.pipchat.in/build/high-tunnel) (tier 5, Food › Protected growing): Steel bows on ground posts under one layer of greenhouse film, with sides that roll up: weeks added to both ends of the season, in the field's own soil. Data: https://civilization101.pipchat.in/data/builds/high-tunnel.json
- [Passive solar greenhouse](https://civilization101.pipchat.in/build/solar-greenhouse) (tier 5, Food › Protected growing): A greenhouse that heats itself: a heavy, insulated wall on the side away from the sun, film on the sunny side, and a blanket over the film at night. Data: https://civilization101.pipchat.in/data/builds/solar-greenhouse.json
- [Drainable fish pond, 400 m²](https://civilization101.pipchat.in/build/fish-pond) (tier 2, Food › Aquaculture): A 20 × 20 m earthen pond with rammed dikes, a screened inlet and a wooden monk: filled and drained by gravity, manured from the farm, and harvested every six months. Data: https://civilization101.pipchat.in/data/builds/fish-pond.json
- [Family drip kit, 500 m²](https://civilization101.pipchat.in/build/drip-kit) (tier 5, Food › Crops and soil): A covered tank 1–1.5 m up, a valve, a 120-mesh filter, a 25 mm main and 8 mm dripper lines: drip irrigation for a family plot by gravity, with no pump and no power. Data: https://civilization101.pipchat.in/data/builds/drip-kit.json
- [Nutrient-film bench for lettuce](https://civilization101.pipchat.in/build/nft-hydroponics) (tier 5, Food › Protected growing): Eight covered channels 6 m long on a bench falling 2 %, a pump in a covered tank, and a film of solution 1–2 mm deep: lettuce without soil in 30–50 days. Data: https://civilization101.pipchat.in/data/builds/nft-hydroponics.json

## Field guides

Practical knowledge that is neither a single step nor a single object — techniques, identification, and what will hurt you. Each guide ends with its own list of what is still missing. Page: https://civilization101.pipchat.in/guides

- [Fire](https://civilization101.pipchat.in/guide/fire) (tier 0, Energy › Fire and fuel): Making fire once is a trick. Never having to make it from nothing again is the skill, and the difference between them is tinder you collected yesterday. Data: https://civilization101.pipchat.in/data/guides/fire.json
- [Drinking water](https://civilization101.pipchat.in/guide/water) (tier 0, Water › Make water safe): The thing that kills first, and the one problem on this site that is completely solved — provided you do it every single day, including the day everyone is exhausted. Data: https://civilization101.pipchat.in/data/guides/water.json
- [Fish and water foods](https://civilization101.pipchat.in/guide/fishing) (tier 0, Food › Wild food): The highest calorie-return food source available to a group with nothing — and the one most often worked in the least productive way. Data: https://civilization101.pipchat.in/data/guides/fishing.json
- [Foraging](https://civilization101.pipchat.in/guide/foraging) (tier 0, Food › Wild food): Wild plants and fungi are mostly water, fibre and vitamins. A handful of them are food worth carrying home, a handful will kill you in a way no taste, smell or cooking can warn you about, and the difference is knowledge you hold before you pick. Data: https://civilization101.pipchat.in/data/guides/foraging.json
- [Sanitation and disease](https://civilization101.pipchat.in/guide/sanitation) (tier 0, Water › Sanitation): The distance between a latrine and a well, a bar of soap, and a covered pit prevent more deaths than every hospital on the ladder combined. Data: https://civilization101.pipchat.in/data/guides/sanitation.json
- [Wild water and wells](https://civilization101.pipchat.in/guide/wells) (tier 0, Water › Find and store water): Surface water is a treatment problem every single day. Groundwater, reached and sealed properly, is a treatment problem once. Data: https://civilization101.pipchat.in/data/guides/wells.json
- [Lime](https://civilization101.pipchat.in/guide/lime) (tier 2, Materials › Binders): Burn a rock, add water, and it turns back into rock in the shape you gave it. Mortar, plaster, whitewash, soap and tanning all start there — and so does an alkali burn that can blind in seconds. Data: https://civilization101.pipchat.in/data/guides/lime.json
- [Charcoal](https://civilization101.pipchat.in/guide/charcoal) (tier 2, Energy › Fire and fuel): Throw away two-thirds of the energy in a pile of wood and what is left is the only fuel that reaches the temperature of molten iron. Data: https://civilization101.pipchat.in/data/guides/charcoal.json
- [Food preservation](https://civilization101.pipchat.in/guide/preservation) (tier 1, Food › Storage and preservation): A glut eaten in the week it arrives is a feast. The same glut dried, salted, fermented or cellared is the difference between March and a famine. Data: https://civilization101.pipchat.in/data/guides/preservation.json
- [Wood and the forest](https://civilization101.pipchat.in/guide/wood) (tier 1, Tools › Woodworking): The forest is the first material store, the first fuel supply and the first thing a group kills itself cutting down. Managed, it is also the only one of the three that grows back. Data: https://civilization101.pipchat.in/data/guides/wood.json
- [Livestock husbandry](https://civilization101.pipchat.in/guide/livestock) (tier 1, Food › Livestock): Animals turn grass nobody can eat into milk, meat, wool, leather, manure and traction. They also turn raw milk, a birthing ewe and a dog fed on offal into diseases that kill people. Data: https://civilization101.pipchat.in/data/guides/livestock.json
- [Smithing](https://civilization101.pipchat.in/guide/smithing) (tier 2, Tools › Metalworking): Iron is shaped by colour. Read the heat right and a bar of scrap becomes a chisel that holds an edge; read it wrong and it cracks, burns, or stays as soft as a nail. Data: https://civilization101.pipchat.in/data/guides/smithing.json
- [Clay and firing](https://civilization101.pipchat.in/guide/clay) (tier 1, Materials › Ceramics and glass): Fired clay is the first material a group makes that does not exist in nature: a rock with a shape you chose. Getting there is mostly patience — in the drying, and in the heating. Data: https://civilization101.pipchat.in/data/guides/clay.json
- [Navigation and the sky](https://civilization101.pipchat.in/guide/navigation) (tier 2, Transport › On water): North is written in the sky twice a day and all night. Latitude is one angle measured at noon. Everything else is counting paces and not lying to yourself about the count. Data: https://civilization101.pipchat.in/data/guides/navigation.json
- [Wound care and first aid](https://civilization101.pipchat.in/guide/first-aid) (tier 0, Health › First aid and surgery): Without antibiotics, a cut is a slow emergency and a deep bite is a fast one. What saves people is mostly pressure, water, and knowing which wounds must be left open. Data: https://civilization101.pipchat.in/data/guides/first-aid.json
- [Micro-organisms](https://civilization101.pipchat.in/guide/microbes) (tier 3, Health › Hygiene and disease): The two dozen that decide who lives where there is no doctor: what each does, how it spreads, what kills it and which step stops it. Data: https://civilization101.pipchat.in/data/guides/microbes.json
- [The sciences](https://civilization101.pipchat.in/guide/sciences) (tier 3, Knowledge › Science and measurement): Fourteen branches, each with the handful of results a civilization cannot rebuild without, and where to learn the rest. Data: https://civilization101.pipchat.in/data/guides/sciences.json
- [Essential medicines](https://civilization101.pipchat.in/guide/medicines) (tier 3, Health › Medicines): The basic set from the WHO list: what each treats, what it is made from, and the earliest tier that can make it. No doses, on purpose. Data: https://civilization101.pipchat.in/data/guides/medicines.json
- [The body's numbers](https://civilization101.pipchat.in/guide/physiology) (tier 1, Health › First aid and surgery): Normal pulse, breathing, temperature and blood pressure; the signs that mean danger in a child; and how much water a body needs. Data: https://civilization101.pipchat.in/data/guides/physiology.json
- [Poisons](https://civilization101.pipchat.in/guide/poisons) (tier 1, Health › First aid and surgery): The poisonings a rebuilding community is most likely to meet: where each comes from, how it shows, and the first thing to do. Data: https://civilization101.pipchat.in/data/guides/poisons.json
- [Calculating by hand](https://civilization101.pipchat.in/guide/tables) (tier 3, Knowledge › Teaching): Four-figure logarithms and trigonometry, square roots by Newton's method, and the two instruments that did the world's arithmetic before electronics. Data: https://civilization101.pipchat.in/data/guides/tables.json
- [Properties of materials](https://civilization101.pipchat.in/guide/materials-data) (tier 3, Shelter › Building materials): Density, stiffness, expansion and melting point for the materials the ladder makes, and what each number decides. Data: https://civilization101.pipchat.in/data/guides/materials-data.json
- [Minerals and ores](https://civilization101.pipchat.in/guide/ores) (tier 2, Materials › Metals): How to tell the ores that matter with nothing but a streak plate, a knife and your hand: colour lies, streak and weight do not. Data: https://civilization101.pipchat.in/data/guides/ores.json
- [Soils and plant nutrition](https://civilization101.pipchat.in/guide/soils) (tier 1, Food › Crops and soil): What a soil is made of, why its acidity matters, and how to read a nutrient shortage in the leaves before it costs a harvest. Data: https://civilization101.pipchat.in/data/guides/soils.json
- [The electromagnetic spectrum](https://civilization101.pipchat.in/guide/spectrum) (tier 5, Computing › Signals): Radio, heat, light, ultraviolet and X-rays are one thing at different wavelengths: what each band does, and the radio bands by name. Data: https://civilization101.pipchat.in/data/guides/spectrum.json
- [Hunting and trapping](https://civilization101.pipchat.in/guide/hunting) (tier 0, Food › Wild food): A trapline works all night while you sleep. A hunt works only while you are awake, usually returns nothing, and burns the calories it was supposed to find. Data: https://civilization101.pipchat.in/data/guides/hunting.json
- [Rope, knots and lashings](https://civilization101.pipchat.in/guide/knots) (tier 0, Materials › Fibres, textiles and leather): A dozen knots cover almost everything. Two of the most familiar ones — the reef knot and the granny — have killed people who used them for the one job they cannot do. Data: https://civilization101.pipchat.in/data/guides/knots.json
- [Seeds and the growing year](https://civilization101.pipchat.in/guide/seeds) (tier 1, Food › Crops and soil): A seed is a living embryo with a shelf life. Kept dry and cold it waits for years; kept warm and damp it dies in a season — and the difference is two rules of thumb and a sealed jar. Data: https://civilization101.pipchat.in/data/guides/seeds.json
- [Stone and earth building](https://civilization101.pipchat.in/guide/building) (tier 1, Shelter › Dwellings): How to build a dwelling that stays dry and standing for thirty years from subsoil, stone and timber: choosing the method, setting out, foundations, walls, roof, drainage, and how to inspect, repair and maintain it. Data: https://civilization101.pipchat.in/data/guides/building.json
- [Fibre to cloth](https://civilization101.pipchat.in/guide/fibre) (tier 1, Materials › Fibres, textiles and leather): Cloth is a chain of slow jobs — growing, retting, spinning, weaving, finishing — and for all of history the slowest link was spinning. A weaver needed several spinners working full time to keep one loom supplied. Data: https://civilization101.pipchat.in/data/guides/fibre.json
- [Electricity](https://civilization101.pipchat.in/guide/electricity) (tier 5, Energy › Electricity): Not a source of energy but a way of carrying it: make it, move it, store it — and know exactly how it kills. Data: https://civilization101.pipchat.in/data/guides/electricity.json
- [Energy sources](https://civilization101.pipchat.in/guide/energy) (tier 7, Energy › Electricity): Every source of energy in one place: what it gives, what it takes, and how it can hurt you. Key figures, a reference sheet for each, and where to read further. Data: https://civilization101.pipchat.in/data/guides/energy.json
- [Planning a settlement](https://civilization101.pipchat.in/guide/planning) (tier 0, Settlements › Settlement and planning): Where to put a settlement and how to lay it out, from a first night's camp to a town: the numbers that keep fire, flood and foul water away from where people sleep. Data: https://civilization101.pipchat.in/data/guides/planning.json
- [Sustainable farming](https://civilization101.pipchat.in/guide/farming) (tier 1, Food › Crops and soil): Keep the soil covered, feed it, water the roots and fight pests without poisoning yourself: the modern practice that needs knowledge rather than machinery. Data: https://civilization101.pipchat.in/data/guides/farming.json
- [Boats and water travel](https://civilization101.pipchat.in/guide/boats) (tier 1, Transport › On water): Which boat to build from what you have, how much it carries before it swamps, what keeps it upright, and the rules that keep its crew alive: from a log raft to a fibreglass skiff. Data: https://civilization101.pipchat.in/data/guides/boats.json
- [Flight](https://civilization101.pipchat.in/guide/flight) (tier 2, Transport › In the air): How a surface in moving air makes lift, how much a balloon carries, how kites and models are balanced, and why every flying machine is tested without a person in it first. Data: https://civilization101.pipchat.in/data/guides/flight.json
- [Greenhouses](https://civilization101.pipchat.in/guide/greenhouse) (tier 3, Food › Protected growing): What a greenhouse is for, which kind to build, its parts and how to size them, and how to run its climate: from a cold frame over manure to a heated glasshouse and a solar greenhouse that needs no fuel. Data: https://civilization101.pipchat.in/data/guides/greenhouse.json
- [Institutions: what to found, and how to run them](https://civilization101.pipchat.in/guide/institutions) (tier 0, Society › Deciding together): Every public institution an advanced civilisation runs, in the order a rebuilding one can found them: what each is for, when it becomes possible, and the rules that keep it honest, useful and no bigger than its job. Data: https://civilization101.pipchat.in/data/guides/institutions.json
- [Fish farming in ponds](https://civilization101.pipchat.in/guide/aquaculture) (tier 2, Food › Aquaculture): A drainable earthen pond, manured from the farm's animals, grows fish without bought feed: site, species, water, stocking, feeding, daily care and harvest. Data: https://civilization101.pipchat.in/data/guides/aquaculture.json
- [Mathematics](https://civilization101.pipchat.in/guide/mathematics) (tier 3, Knowledge › Teaching): The results every other science and machine is built on, in the order each needs the last: the formula, what it states, what it lets you do, and who first found it. Data: https://civilization101.pipchat.in/data/guides/mathematics.json
- [Biology](https://civilization101.pipchat.in/guide/biology) (tier 3, Health › First aid and surgery): Life from the cell up: the human body, microbes and immunity, inheritance and epidemics. Each result with what it lets you do and who first found it. Data: https://civilization101.pipchat.in/data/guides/biology.json
- [Physics](https://civilization101.pipchat.in/guide/physics) (tier 3, Knowledge › Science and measurement): Force, energy, heat, light, electricity, relativity and the atom: the laws every engine, wire and lens obeys, each with what it lets you do and who first found it. Data: https://civilization101.pipchat.in/data/guides/physics.json
- [Chemistry](https://civilization101.pipchat.in/guide/chemistry) (tier 3, Materials › Chemicals): What matter is made of and how it changes: amounts, gases, acids, the energy and speed of reactions, electrochemistry, and the reactions every industry on the ladder runs on. Data: https://civilization101.pipchat.in/data/guides/chemistry.json
- [Astronomy](https://civilization101.pipchat.in/guide/astronomy) (tier 3, Knowledge › Science and measurement): The sky as calendar, clock and compass, then orbits, distances and the universe: each result with what it lets you do and who first found it. Data: https://civilization101.pipchat.in/data/guides/astronomy.json
- [Earth sciences](https://civilization101.pipchat.in/guide/earth-sciences) (tier 3, Water › Find and store water): Water in and on the ground, the air and weather, rocks and time, earthquakes and tsunamis, and the climate: each result with what it lets you do and who first found it. Data: https://civilization101.pipchat.in/data/guides/earth-sciences.json
- [Engineering](https://civilization101.pipchat.in/guide/engineering) (tier 3, Tools › Production): Turning the sciences into things that work: machines, structures, water in pipes and channels, heat through walls, and feedback control. Each result with what it lets you do and who first found it. Data: https://civilization101.pipchat.in/data/guides/engineering.json
- [Computer science](https://civilization101.pipchat.in/guide/computer-science) (tier 6, Computing › Electronics and computing): What can be computed and how fast, how signals carry information without error, how secrets are kept, and how machines learn from data: each result with what it lets you do and who first found it. Data: https://civilization101.pipchat.in/data/guides/computer-science.json
- [Electronics and computer hardware](https://civilization101.pipchat.in/guide/electronics) (tier 6, Computing › Electronics and computing): From a relay to a stored-program computer: what makes a switch compute, diodes and transistors, logic, memory, the processor, and how chips are made, each with the numbers that decide it. Data: https://civilization101.pipchat.in/data/guides/electronics.json

## The better path

Choices the record says to make differently: things adopted widely that caused lasting harm, and cheap fixes that arrived centuries late. Each sits on the step where the choice is made, with the alternative available at that tier and the evidence. Page: https://civilization101.pipchat.in/better

### Adopt earlier

- [Keep the latrine away from the well](https://civilization101.pipchat.in/step/t0-latrine) (tier 0, Separate waste from water): Site every latrine at least 30 m from, and downhill of, every well, spring and stream.
- [Plant through the residue instead of ploughing the ground bare](https://civilization101.pipchat.in/step/t1-clear) (tier 1, Open ground and hold fertility): Keep at least 30 % of the soil covered with residue, mulch or a cover crop, open the ground only where the seed goes — a pointed planting stick makes the hole — and grow at least three different crops in sequence.
- [Compost hot before it goes on food crops](https://civilization101.pipchat.in/step/t1-clear) (tier 1, Open ground and hold fertility): Build the pile at a carbon-to-nitrogen ratio near 30:1, keep it as damp as a wrung-out sponge, and hold it at 55 °C or more for at least 15 days, turning it at least five times, before it goes near a crop that is eaten raw.
- [Push-pull against stemborers and Striga](https://civilization101.pipchat.in/step/t1-staples) (tier 1, Plant staples): Drill Desmodium between the maize rows and plant three rows of Napier or Brachiaria grass round the plot: the Desmodium drives stemborer moths out and makes Striga seed germinate and die, and the grass border draws the moths in to lay their eggs where the larvae do not survive.
- [Citrus and greens against scurvy](https://civilization101.pipchat.in/step/t1-nutrition) (tier 1, Prevent deficiency disease): Give anyone living on stored food a raw vitamin C source every day: greens, sprouts, sauerkraut, potatoes or fruit. About 10 mg a day prevents scurvy.
- [Cook maize in alkali](https://civilization101.pipchat.in/step/t1-nutrition) (tier 1, Prevent deficiency disease): Simmer every batch of maize in 1% slaked lime or wood-ash lye until the skins slip, steep it overnight and rinse it; eat beans with it.
- [Parboil rice before milling](https://civilization101.pipchat.in/step/t1-nutrition) (tier 1, Prevent deficiency disease): Soak and steam paddy in its husk before milling, or eat rice lightly milled; eat pulses or groundnuts with it.
- [Take the cooking fire out of the sleeping room](https://civilization101.pipchat.in/step/t1-dwelling) (tier 1, Plan the house: sun, air, smoke and damp): Cook outdoors under a shade roof or in a separate cookhouse in warm climates; in cold climates give the hearth its own room and a flue, and never sleep beside a banked fire.
- [Wash hands between patients](https://civilization101.pipchat.in/step/t1-midwifery) (tier 1, Childbirth and infant survival): Wash hands with soap before touching a woman in labour, and between every patient.
- [Kangaroo mother care for small babies](https://civilization101.pipchat.in/step/t1-midwifery) (tier 1, Childbirth and infant survival): Keep a baby under 2 kg skin to skin on the mother's or another adult's chest, upright, day and night, breastfed on demand, from as soon after birth as possible.
- [Oral rehydration: salt, sugar and water](https://civilization101.pipchat.in/step/t2-salt) (tier 2, Salt): 1 litre of safe water, 6 level teaspoons of sugar and ½ level teaspoon of salt — or, without sugar, 50–80 g of rice flour boiled in the litre with the salt. Doses are in separate waste from water.
- [A float for everyone aboard](https://civilization101.pipchat.in/step/t2-plank-boats) (tier 2, Plank boats, oars and sail): From the first plank boat, carry a float for every person aboard — cork, sealed gourds, closed containers or a rated lifejacket — and wear it on cold or rough water.
- [Citrus against scurvy from the first long voyage](https://civilization101.pipchat.in/step/t3-ships) (tier 3, Seagoing sailing ships): Carry a daily source of vitamin C on every passage longer than a month — citrus or its juice, potatoes, sauerkraut, or grains and pulses sprouted aboard — and check the store is fresh.
- [Lifeboats and lifejackets for everyone aboard](https://civilization101.pipchat.in/step/t4-steamships) (tier 4, Steam, iron hulls and the load line): From the first passenger ship, boat places and a lifejacket for every person aboard.
- [Measure in a wind tunnel before building](https://civilization101.pipchat.in/step/t4-gliders) (tier 4, Gliders and the control problem): Build a small wind tunnel and measure every wing shape before cutting a spar.
- [Chlorinate the supply](https://civilization101.pipchat.in/step/t4-sanitation) (tier 4, City water and sewerage): After filtration, dose chlorine to leave at least 0.5 mg/l free chlorine after 30 minutes of contact, and at least 0.2 mg/l at the far end of the network.

### Do not repeat

- [Lead where it can reach a mouth](https://civilization101.pipchat.in/step/t2-smelt) (tier 2, Smelting: first metal): Keep lead out of anything that holds food, drink or water, and off surfaces children touch: unglazed or high-fired pots, iron, wood and stone for vessels, and limewash for walls. Use lead for roofing, weights and acid chambers.
- [Bloodletting and purging](https://civilization101.pipchat.in/step/t2-medicine) (tier 2, Plant medicine and the pharmacy): Do not bleed or purge the sick. Keep them warm, rested and drinking, and replace lost fluid with oral rehydration solution.
- [Census returns used against the people counted](https://civilization101.pipchat.in/step/t2-census) (tier 2, Count before you administer): Write into the census law that individual returns are used only to make statistics, are never passed to any office that acts on named people, and are sealed for a century.
- [Streets only as wide as today's traffic](https://civilization101.pipchat.in/step/t2-plot) (tier 2, Plot, street and block): Survey a grid with the widths reserved from the start, and cut the corners of blocks back so vehicles can turn and see.
- [Fire balloons released free](https://civilization101.pipchat.in/step/t3-balloons) (tier 3, Balloons): Tether every hot-air model and keep the heat on the ground; never let a flame fly.
- [White phosphorus matches](https://civilization101.pipchat.in/step/t3-acid) (tier 3, Acids): Make safety matches: keep phosphorus off the match. Red phosphorus — made by heating white phosphorus without air — goes on the striking strip, and potassium chlorate on the match head.
- [Prison for debt](https://civilization101.pipchat.in/step/t3-contract) (tier 3, The enforceable promise): Enforce debts against property and a share of income only, protect what a household needs to live and work, and discharge an honest debtor's remaining debts after a fixed period.
- [Asbestos lagging](https://civilization101.pipchat.in/step/t4-steam) (tier 4, The steam engine): Lag with mineral wool spun from blast-furnace slag, or with cork. Never saw, sand or break existing asbestos dry.
- [Boilers without tests or safety valves](https://civilization101.pipchat.in/step/t4-steamships) (tier 4, Steam, iron hulls and the load line): From the first steamer: water-pressure tests before use and every year, a safety valve nobody can tie down, a maximum working pressure, and licensed engineers.
- [Loading for the insurance](https://civilization101.pipchat.in/step/t4-steamships) (tier 4, Steam, iron hulls and the load line): Mark a load line on every hull from the first cargo ship, and have the port check it before every departure.
- [Lead water pipes](https://civilization101.pipchat.in/step/t4-sanitation) (tier 4, City water and sewerage): Lay mains in cast iron, and house connections in iron or fired clay.
- [Water supply before sewerage](https://civilization101.pipchat.in/step/t4-sanitation) (tier 4, City water and sewerage): Build the drain with the supply: no house connection to the mains without a connection to a sewer or a properly sized soakaway.
- [Combined storm and foul sewers](https://civilization101.pipchat.in/step/t4-sanitation) (tier 4, City water and sewerage): Lay separate pipes for foul water and rainwater. The trench is most of the cost of a sewer; a second pipe in it is a fraction of the cost of retrofitting one later.
- [CFC refrigerants](https://civilization101.pipchat.in/step/t4-cold) (tier 4, Refrigeration and the cold chain): Keep ammonia in ventilated plant rooms outside occupied space, with small sealed charges where people are near; domestic units can use isobutane once there is refining. Both were known in the 1920s.
- [Public posts given as rewards](https://civilization101.pipchat.in/step/t4-service) (tier 4, Standing departments and a civil service): Fill every permanent post by open, advertised competition on a published standard, and protect officials from dismissal for anything but stated cause.
- [Zoning every use apart](https://civilization101.pipchat.in/step/t4-zoning) (tier 4, Zoning: separation distances, wind, river and flood): Separate only works that emit odour, dust, noise or major-accident risk; mix every compatible use.
- [Leaded petrol](https://civilization101.pipchat.in/step/t5-engine) (tier 5, Internal combustion and mobility): Raise octane by blending 10–20% ethanol from distillation, or by refining; never add lead.

## Essays

The argument behind the ladder's order: what limits progress, what regularities it follows, where it goes next, and how it fails. Full text: https://civilization101.pipchat.in/data/essays.json

- [The six constraints](https://civilization101.pipchat.in/constraints): Technology does not advance because people become cleverer. It advances when a small number of physical limits are pushed back. Almost every step on the ladder is gated by one of these six, and knowing which one you are against tells you what to work on.
- [Patterns of progress](https://civilization101.pipchat.in/patterns): What actually happened over the last twelve thousand years, read as a set of regularities rather than a story. Not great men and lucky inventions — the shape the data makes when you stand far enough back.
- [Futures](https://civilization101.pipchat.in/futures): The same patterns, extended forward. Not prediction — extrapolation, with its confidence marked and its failure modes stated.
- [How it actually fails](https://civilization101.pipchat.in/collapse): The anatomy of collapse, read backwards — because knowing the failure modes is what lets you build against them.

## Library

Every book verified against Project Gutenberg's own catalogue — id, title and author — and fetched over HTTP. Free, legal, downloadable. Bulk archives cover what single books cannot. 205 books and 17 bulk archives. Page: https://civilization101.pipchat.in/library · Full list: https://civilization101.pipchat.in/data/library.json

- Wikipedia, offline (Kiwix ZIM) (~110 GB full with images · ~55 GB no-image · ~5 GB 'best of')
- Hesperian Health Guides (~50–400 MB)
- CD3WD appropriate-technology archive (~13 GB)
- OpenStax textbooks (~2 GB)
- WHO water, sanitation and health guidance (~200 MB)
- UNHCR Emergency Handbook (a website; each entry saves as a PDF)
- WHO, Immunization in Practice (Free PDF download)
- Encyclopædia Britannica, 11th edition (1911) (~1–8 GB depending on format)
- The Survivor Library (~100 GB)
- Appropedia (~4 GB)
- FAO agricultural documents (~10 GB)
- USDA / NRCS soil and conservation library (~5 GB)
- Wood Handbook (USDA Forest Products Laboratory) (one PDF book)
- The Humanure Handbook (~20 MB)
- LibreTexts (~15 GB)
- Project Gutenberg (complete) (~90 GB with all formats · ~15 GB text only)
- Internet Archive (Unbounded — curate)

## Reference pages

- [Explore by subject](https://civilization101.pipchat.in/explore): The sectors — water, food, shelter, settlements, health, energy and the rest — each a set of tracks climbing the eight levels, with what is written at each level and what is not.
- [How-to](https://civilization101.pipchat.in/howto): Every field guide, build and reference sheet, grouped by subject.
- [Ideas](https://civilization101.pipchat.in/ideas): The essays behind the ladder's order, and the better path.
- [Dependency graph](https://civilization101.pipchat.in/graph): Every step and every prerequisite as one navigable map.
- [Where civilization stands](https://civilization101.pipchat.in/scale): Humanity on the Kardashev scale from world energy use, beside the wellbeing, knowledge and sustainability measures that say whether that energy is doing any good; updated yearly.
- [Periodic table](https://civilization101.pipchat.in/elements): All 118 elements; the 30 a rebuilding civilization makes or must handle, with where they come from, how they are obtained and how they harm.
- [Search](https://civilization101.pipchat.in/search): Search every field guide section, step, build, drawing, photograph, reference sheet, subject, essay, element and book; several words find the pages that hold all of them.
- [Take it offline](https://civilization101.pipchat.in/offline): How to mirror this site and its library to physical media, and the single-file offline edition with its sha256 checksum.
- [About & method](https://civilization101.pipchat.in/about): How this was built, how the sources were verified, and what it cannot tell you.
- [Safety, law and terms](https://civilization101.pipchat.in/policies): The specific ways this material can hurt you, expose you, or quietly fail; licensing (CC BY-SA 4.0) and privacy.
- [Contents & Roadmap](https://civilization101.pipchat.in/roadmap): This index, plus what is still missing from the site, counted against the corpus, and the order it is being built in. Data: https://civilization101.pipchat.in/data/roadmap.json