fejkdata/todo.md

todo

Scoring

Score = -R - S/4 + 2*A + 2*G*W

Bar = 9

Next ID = 108

Goal	W
1	1.00
1.1	1.00
2	0.95
2.1	0.95
2.2	0.95
2.3	0.95
3	0.90
3.1	0.90
3.2	0.90
3.3	0.90
3.4	0.90
4	0.85
4.1	0.85
5	0.80
5.1	0.80
5.2	0.80
5.3	0.80
5.4	0.80
5.5	0.80
5.6	0.80
5.7	0.80
5.8	0.80
6	0.75
6.1	0.75
6.2	0.75
7	0.70
7.1	0.70
7.2	0.70
7.3	0.70
8	0.65
9	0.60
9.1	0.60
9.2	0.60
9.3	0.60
9.4	0.60
9.5	0.60
9.6	0.60
10	0.55
10.1	0.55
11	0.50
12	0.45
12.1	0.45
12.2	0.45
12.3	0.45
13	0.40
13.1	0.40
14	0.35
14.1	0.35
15	0.30
16	0.25

Items

ID	Release	Exempt	Item	R	S	A	G	Goals	Score
77	0.1.0	decision	Split the shipped data into Go modules per locale and country, which a library imports by choice, and embed every one in the CLI.	5	10	10	10	2, 1.1, 9	32.5
78	0.1.0	decision	Ship 10% of every place's streets, at least 10, and 10% of all US places drawn by population, each place weighted by population.	6	7	10	10	2, 14.1	31.2
61	0.1.0		Add a locale, with its geo/ tree, for each of the ten most-spoken languages and each Nordic country.	4	9	9	10	2.1	30.8
16	0.1.0		Add the remaining locale categories: company, phone, finance, vehicle, words.	3	8	8	9	2.2, 15	28.1
15	0.1.0		Add the remaining misc tables and templates, one row of its detail's table per chunk.	3	9	8	8	2, 15, 14	25.9
57	0.1.0		Rewrite CHANGELOG.md's [Unreleased] as what v0.1.0 holds.	1	2	6	6	1.1	22.5
34	0.1.0		Add {isin()}, {cusip()}, {aba()} and {vin()}.	2	4	6	7	4	20.9
96	0.1.0		Refuse two reads into one sibling, category or struct category that no name joins, {place.postal-code} {place.locality}, showing the spelling for one pick and the one for two.	4	4	7	7	5.6, 4	20.9
5	0.1.0	decision	Run the nine-seat comprehension panel and larv-review's scoring run once items 97 to 106 have restructured the code, and file what the panel names.	1	3	3	9	3	20.4
91	0.1.0		Accept a path through a name as a calc operand, so {/misc.coordinate as c}{c}: {calc(c.lat * 60)} computes from the coordinate {c} prints.	3	4	6	7	4.1, 5.3	19.9
89	0.1.0		Fail New without WithSeed, naming the option, and seed the CLI from the system.	3	3	6	7	10.1	16.0
102	0.1.0	defect	Move a table's rows and the links between tables into internal/rows, and walk every path through one per-step function, so Fake refuses a level carrying a repeat as the load check does.	5	6	4	8	3.2, 3.4, 5	15.9
97	0.1.0	decision	Move the seeded randomness and its {seq()} counters into internal/drawstate, built from a seed, and test which packages each package may import.	2	4	2	8	3.2, 3.4	15.4
103	0.1.0		Move the folder walk and the reading of a data tree's JSON and TSV files into internal/datafiles, which hands the engine a reader for each table's rows.	3	4	2	8	3.2, 3.4	14.4
98	0.1.0		Move how the template language is written — format tokens, paths and selectors, reference sigils, names and calc syntax — into internal/grammar.	3	5	2	8	3.2, 3.4	14.2
100	0.1.0		Move the builtins, with their checksums, layouts and transforms, into internal/builtinfunc, and check calc's operands where its template links.	3	5	2	8	3.2, 3.4	14.2
106	0.1.0		Settle each record's shape when its template links, so Generator.records goes.	2	2	2	7	3.2	14.1
101	0.1.0		Set a table's path when it compiles, link a table family in one function, and label a cell's template from the walk, so no template points back at its table.	4	4	2	8	3.2	13.4
104	0.1.0		Create a name scope with its owner in one place, and hand a template's name reads to the checks as a returned value, not appended to its bindings.	4	4	2	8	3.2	13.4
79	0.1.0	decision	Beside a --data-path, load in New the user's categories, the shipped ones they override or read, and the shipped ones whose reads reach an overridden one; load the rest on first reach.	6	6	7	8	13	12.9
99	0.1.0		Move DataType into internal/datatype, aliased by the root, and what a proof knows of a value, proven, into internal/proven.	3	4	2	7	3.2, 3.4	12.6
105	0.1.0	principle	Link each template in steps that each return what they build — its references, its bindings' heads and addressed keys, its compiled arms, its column read — so no step writes into what an earlier one built.	6	7	2	9	3.2	12.4
58	0.2.0		Ship prebuilt binaries, a container image, and packages for Homebrew, Scoop and the biggest Linux package managers, so the CLI needs no Go.	3	7	8	9	1.1, 7	29.2
26	0.2.0	defect	Spell sv_SE.personnummer with the + Skatteverket uses from the year the holder turns 100, judged by a date the caller gives.	4	6	7	8	4	22.1
81	0.2.0	decision	Refuse at load every calc operand not proven numeric and every divisor not proven nonzero, in a string column too.	4	4	6	8	6.1, 4	20.6
36	0.2.0		Report every mistake a load finds in one error, as the decision "A load reports every mistake at once" states.	5	6	7	8	6	19.5
88	0.2.0		Add a 12-digit YYYYMMDDNNNC form of sv_SE.personnummer and sv_SE.samordningsnummer, the form Skatteverket's testpersonnummer series and many systems store.	2	3	6	6	4	19.4
41	0.2.0	decision	Key every table by one key column, as the decision "A table selects by one key column, a code, never a free-form name" states.	6	7	7	8	5.5	19.1
52	0.2.0		Name the file a link error comes from beside its category path, sub.x (/d/a/sub/x.json): ….	1	2	5	7	6	19.0
28	0.2.0	decision	Accept a middle name, and draw a personnummer whose sex matches a sex selected through a named pick.	4	4	6	7	4.1	18.9
24	0.2.0	defect	Stop misc.territory[EH].tld rendering .eh, the one shipped TLD misc.tld does not hold.	1	1	4	7	4	18.6
92	0.2.0		Name the hyphenated field in a calc's refusal, and say to rename it: today {calc(postal-code * 2)} reports no field "postal".	1	2	5	6	6	17.5
53	0.2.0		Let a table column carry a datatype, so --format json writes "safe": true and --format sql a boolean.	4	5	6	6	4	16.9
55	0.2.0		Document NewRecordTemplate, ErrNoColumns, ErrNoData and MaxRepeat in the README's Library section.	1	2	6	7	12	16.8
18	0.2.0		Give the address records one column set across countries: region and municipality as columns on geo.SE.address too.	4	4	6	6	5	16.6
44	0.2.0	decision	Have misc.tld[se] select the row keyed .se, or have its miss name [.se].	1	1	4	6	6	15.8
54	0.2.0	defect	Read the tag through git/ref/tags/{tag} in publish_release.py.	2	1	3	6	1.1	15.8
31	0.2.0		Rename misc.territory.country to sovereign.	3	2	4	7	5.8	15.7
20	0.2.0	defect	Weight sv_SE.sex and en_US.sex by bearers, as the README's Data section says they are.	2	2	4	6	4	15.7
50	0.2.0		Reword prove's refusal of a typed column reading a row, {/region}.	1	2	4	6	6	15.5
17	0.2.0		Give every shipped category a column for each part its format composes, and one record shape across the national ids; re-pin the shape.	5	6	6	6	5	15.1
29	0.2.0		Let a path go from a selected row into the template beside its family: geo.US.locality[1714000].address.	4	4	5	6	5	14.6
42	0.2.0		Refuse a struct tag's datatype naming the Go type that sets it before proving its values, as the README's Library section promises.	2	2	4	6	6	14.5
32	0.2.0		Add misc.browser as the parent of misc.useragent, so misc.browser[Chrome].useragent resolves.	3	3	4	6	4.1	14.4
27	0.2.0		Merge en_US.ip and sv_SE.ip, today byte-identical, into one misc.ip.	3	2	4	6	5.7	14.1
22	0.2.0		Give url and email a path that draws only domains nobody can register, keeping the wide set as the default.	3	4	7	8	16	14.0
46	0.2.0		Report the same error every load for a table with two bad options, and for a folder with two unnamed rows files.	2	2	3	7	6, 10	14.0
107	0.2.0	decision	Move the template engine into internal/, leaving the root the public API and its options.	6	9	3	8	3.2, 3.4	12.2
94	0.2.0		Refuse a name whose every read passes one deeper level, naming the binding of that level: {place as p}{p.geo.town.name} {p.geo.town.zip} is {place.geo.town as t}{t.name} {t.zip}.	3	3	3	5	5.7	10.2
14	0.3.0		Spell misc.creditcard's digit runs {digits(n)}.	2	2	4	6	5.7	15.1
38	0.3.0	defect	Compare calcParser.binary's operator as a rune.	1	1	3	6	6	13.8
45	0.3.0		Name the node a selector follows in stepInto's refusal.	1	1	3	6	6	13.8
49	0.3.0		Report a CRLF rows file holding only its header as having no rows.	1	1	3	6	6	13.8
13	0.3.0	defect	Place xlsx cells by their r reference in data-import/xlsx.py.	2	2	3	6	4	13.7
39	0.3.0		Stop the columnKinds suggestion naming a field's own kind or a narrower one.	1	2	3	6	6	13.5
51	0.3.0		Spell a table one way across the errors that name it.	1	2	3	6	6	13.5
10	0.3.0		Test that every node kind reaches each switch over node kinds.	1	3	2	6	3.2	13.1
11	0.3.0		Test that every geo tree holds the five table names and the address columns that port across countries.	1	2	3	5	4	13.0
35	0.3.0		Add {base64url(n)} for JWT shapes.	1	2	4	5	8	13.0
21	0.3.0		List title in both locales, and sv_SE's birth-number, in the README's Data list of what each locale carries.	1	1	4	6	12	12.2
30	0.3.0		Draw email.local from username, so the two share one handle list.	2	2	3	5	5.7	11.5
40	0.3.0		Parse defaultTable's path with the library's grammar.	2	2	3	5	5.7	11.5
86	0.3.0		Read both en_US.phone formats' area codes from one category, as their exchange reads en_US.phone-exchange.	1	2	2	5	3.2	11.5
23	0.3.0		Give every other shipped category that could reach something real a path that never does.	3	6	6	7	16	11.0
75	0.3.0		Run every README sh, go and text example as a test, and compare each "Renders" line to a seeded render.	2	6	4	7	12.2	10.8
33	0.3.0		Group data/misc into folders where a group name makes a path easier to guess.	4	5	4	5	5	10.8
47	0.3.0	defect	Refuse a category naming a hidden rows file, "rows": ".x.tsv", as a rows file that is not there.	1	1	2	5	6	10.2
72	0.3.0	principle	Fail the merge gate when test coverage falls below the last recorded figure.	2	3	2	5	3	10.2
43	0.3.0		Call templateError a compile failure in its doc.	1	1	1	5	3.3	9.8
95	0.3.0	principle	Hold a struct's columns and the field each fills in one slice.	1	2	1	5	3.2	9.5
19	0.3.0		Fill the 398 Swedish localities weighted 200 from SCB småorter.	2	4	4	6	14.1	9.2
56	0.3.0	defect	Build on a manual run of test.yml.	1	1	1	4	1	8.8
63	0.4.0		Pair a street with its exact postnummer.	3	6	5	8	4.1	19.1
62	0.4.0		Add {btc()} and {eth()}.	2	4	4	6	4	15.2
59	0.4.0		Promise in Generator's godoc that its renders run one at a time.	1	1	5	5	12	13.2
65	0.4.0		Hold every change AGENTS.md says owes a CHANGELOG.md entry to one in CI.	2	3	4	5	5.8	13.2
66	0.4.0		Cut the README's Layout block to the lines that say what a file name cannot.	1	1	2	5	3.4	11.8
67	0.4.0		Cut AGENTS.md to the rules only it states, and explain every term its comprehension rule uses.	1	2	1	6	3.4	11.3
64	0.4.0		Give every entry in docs/decisions.md the goal it serves, its date, who made it and the premise it rests on.	1	4	1	6	3.4	10.8
68	0.4.0	decision	Make gitea.larvit.se/larvit/fejkdata a pull mirror of GitHub.	2	1	1	3	1.1	5.8
69	1.0.0		Announce v1.0.0 where a developer choosing a fake-data tool already reads, with a README first screen for someone deciding in a minute.	1	3	7	9	1.1	30.2
70	1.0.0		Publish a homepage with an in-browser generator, the library compiled to WebAssembly.	3	6	6	6	1.1	19.5

Details

77. Split the shipped data into Go modules per locale and country, which a library imports by choice, and embed every one in the CLI.

The CLI binary may grow to hundreds of MB. The maintainer decided on 2026-10-04, under goals 2.3, 6.2, 7.3, 9 and 10.1:

• One module per locale, one per country's geo/ tree, and one for misc. A module registers nothing when imported.
• A bare New() loads no data and fails, naming the option to add. WithoutShippedData goes.
• A data module is an fs.FS passed to WithDataFS, as anyone's data is, and New takes several. A module carrying functions loads through an option of its own, so a data module that starts carrying functions breaks its users.
• A module names, in a manifest, every module it reads by default, directly or through another, so the first error names the whole set to import. A manifest is optional: a --data-path folder without one is a module. A read nothing provides fails, naming the module that provides that path by default or saying none does. Nothing loads a default on its own, and anything providing the same paths stands in.
• A module's manifest names the fejkdata version it was built for, and a mismatch fails in New, naming the go get line that aligns them. Each shipped module requires the core at its own version.
• Every shipped module releases in lockstep, under one version number, so the README's one version still covers the library, the CLI and the data. CI cuts one tag per module per release, which revises the decision "The changelog heading is the one spelling of a release; CI cuts the tag".
• Two sources defining one name fail to load, unless an option says the second replaces the first; every read of that name, a shipped module's included, then reads the second. In the CLI, a flag standing on its own, benched with the data and hand fixture authors, does the same for a --data-path, so flags still go anywhere on the line. This revises the decisions "A --data-path override rebinds every reference to the category it replaces" and "With only the shipped set, a category loads on the first call reaching it; beside a --data-path, every category loads in New".
• The builtins stay in fejkdata itself. A module's function asks for the inputs it needs through one generic mechanism, and gets the randomness and the date the generator uses. The README asks for functions with no side effects of their own.
• The CLI is a library call. One exported list names every shipped module, and fejkdata's own main passes it to that call. The list lives where no library user's module graph pulls in every shipped module, and the architect places it. A custom CLI is the same few lines with other modules added, and no code exists only for custom CLIs. A README section shows it with example code, and the README's Library quick start shows the whole import block for one locale. The README's Versioning section gives each module's tag spelling, and says to pin every fejkdata module at one version.

Split it into items before starting. Before the module API ships, a panel of the README's audience personas tries pulling in data with it.

78. Ship 10% of every place's streets, at least 10, and 10% of all US places drawn by population, each place weighted by population.

Needs item 77. Ten streets per place crowds 500 Stockholm customers onto ten streets. geo-se.py and geo-us.py keep 10% of each place's streets, at least 10. geo-us.py draws 10% of every Census place, down to the smallest village, picking each with odds by population, and every table weights a place by its population, so a draw is not mostly tiny villages. Replaces the decision "The default embed holds every Swedish postort the import can place and give a street-delivery code and a street, and the US places of 25,000 or more", which the maintainer withdrew on 2026-10-03. Re-pin seeded output and the shape in their own commits.

61. Add a locale, with its geo/ tree, for each of the ten most-spoken languages and each Nordic country.

Pick the ten from a published ranking of languages by total speakers, such as Ethnologue's, each in the country where it has the most speakers, and record the ranking in the decision that names them. The Nordic ones are sv_SE (shipped), nb_NO, da_DK, fi_FI and is_IS. Each locale carries goal 2.2's categories, and its address reads its country's geo/ tree by reference.

16. Add the remaining locale categories: company, phone, finance, vehicle, words.

Shape: T = table, t = template, c = choice.

sv_SE (source research)

Category	Shape	Source	Licence
person title, birthdate, age, blood type weighted	t	geblod.nu distribution	facts
organisationsnummer by form, vat	t	Bolagsverket group digits, Luhn, SE…01	facts
company name patterns, legal form weighted	t	Bolagsverket registrations 2025	CC BY 2.5 SE
sni industry codes	T	SCB SNI 2025	"Källa: SCB"
ssyk occupations	T	SCB SSYK 2012	"Källa: SCB"
phone mobile, fixed per area code, E.164	T+t	PTS numbering plan 2024	facts
bankgiro, plusgiro, bankaccount clearing + Luhn/mod-11	T+t	Bankinfrastruktur CSV, Bankgirot rules	facts
licenseplate ABC 123, ABC 12A, blocked combinations	t	Transportstyrelsen	facts
car make, model weighted by registrations	T	Mobility Sweden 2025	cite
word noun, verb, adjective, adverb; sentence	T+t	SALDO	CC BY 4.0
month and weekday names, holiday	t+T	CLDR sv, lag 1989:253	Unicode
territory localised names keyed by alpha2	T	CLDR sv territory names	Unicode

en_US (source research, and part1–part4)

Category	Shape	Source	Licence
ein valid ranges	t	IRS	facts
company names, suffix, naics	t+T	SEC tickers for patterns, NAICS 2022	public domain
phone NANP with valid NPA (the NXX ships as en_US.phone-exchange)	t	NANPA rules	facts
routing ABA with check, bankaccount	t	Fed prefix ranges	facts
licenseplate per state	T	hand-authored patterns	facts
car make, model	T	NHTSA vPIC	public domain
word, sentence, paragraph	T+t	Moby POS or WordNet	public domain / WordNet
month and weekday names, holiday	t+T	CLDR en	Unicode

15. Add the remaining misc tables and templates, one row of its detail's table per chunk.

Shape: T = table, t = template, c = choice.

Category	Shape	Source	Licence
ip v4 documentation ranges, private, CIDR; ipv6 2001:db8::/32; mac locally administered	t	RFC 5737, 1918, 9637	facts
creditcard per network: IIN, length, CVV, expiry	T+t	network rules, {luhn()}	facts
bic, isin, cusip	t	structure rules	facts
ean, upc, gtin, isbn, issn, imei, asin, sku	t	check-digit rules, GS1 demo prefix 952	facts
product name, adjective, material, department, garmentsize	T/c	LLM-written lists	—
airport IATA, ICAO, territory, municipality; airline; aircraft; flight, seat, pnr	T+t	OurAirports, Wikidata	public domain, CC0
element, unit, planet	T	PubChem, BIPM, NASA	public domain, CC BY 4.0
animal by class, plant	T	Wikidata	CC0
bloodtype weighted (global)	c	AABB	facts
color named, hex, rgb, hsl, cmyk	T+t	CSS Color 4, XKCD	W3C, CC0
programminglanguage, os, browser, database column/type/engine, fileext	T/c	Linguist, curated	MIT
commit message, branch, sha	t	LLM-written, {hex(40)}	—
password, hash, jwt, slug, hostname, avatar, placeholderimage	t	shapes	—
book title, author; genre; instrument; dish, ingredient	T	Gutenberg catalog, MusicBrainz, USDA	CC0
lorem, hacker, hipster, catchphrase, buzzword, quote	T/c	lorem ipsum, LLM-written	—
direction, continent, ulid	c/t	—	—

57. Rewrite CHANGELOG.md's [Unreleased] as what v0.1.0 holds.

Nothing has shipped, so "no longer paths", "where it used to fail" and "where it used to be an empty string" describe versions no reader can have installed.

34. Add {isin()}, {cusip()}, {aba()} and {vin()}.

isin: Luhn over letters expanded to digits. aba: 3-7-1 weights. vin: position 9 over the whole; a sample taking the WMI, since the check sits mid-string.

96. Refuse two reads into one sibling, category or struct category that no name joins, {place.postal-code} {place.locality}, showing the spelling for one pick and the one for two.

Asked of the maintainer by the product-owner pass of the chunk that made every {…} draw afresh. Since every {…} draws afresh, {net} x {qty} = {calc(net * qty, 2)}, {place.postal-code} {place.locality} and struct tags sv_SE.address.street beside sv_SE.address.postal-code load and may render a pair that disagrees, and nothing tells the author to bind a name (goal 4.1). Goal 5.6 asks such a template to fail, showing {place as p}{p.postal-code} {p.locality} for one place and two names for two. The decision "Every {…} draws afresh, and only a name keeps a pick" lists the draw checks as names, paths through names, cycles and the repeat cap, so this fence revises it. {w} {w}, one spelling twice, stays two draws. The maintainer answered yes on 2026-10-05, for reads inside one category or one struct; reads across categories, {/city.name}, {/country.name}, keep loading.

5. Run the nine-seat comprehension panel and larv-review's scoring run once items 97 to 106 have restructured the code, and file what the panel names.

Until a panel scores 7.0 or above, only items 97 to 106 and the exceptions in AGENTS.md's comprehension rule merge. The decision "comprehension floor: every dimension and the overall at 7.0 or above; the change making every {…} draw afresh and items 97 to 106 ship with no scoring run, and item 5 scores them" suspends every scoring run and panel until this item runs.

91. Accept a path through a name as a calc operand, so {/misc.coordinate as c}{c}: {calc(c.lat * 60)} computes from the coordinate {c} prints.

A calc operand parses as a bare identifier, so {calc(c.lat * 60)} fails with unexpected ".lat * 60", and a second binding of /misc.coordinate.lat would draw another coordinate. Resolve the path through linkName's leaves, as operandNodes does for a bare name.

89. Fail New without WithSeed, naming the option, and seed the CLI from the system.

Goal 10.1 has the caller supply the seed, and today New without WithSeed seeds itself. This item ships in 0.1.0 beside item 77, so New breaks once before anyone depends on it. Mark WithSeed required in the Library section's options table. Its tests then stop swapping randomBytes, as fejkdata_test.go does today, which fails every New in the package while that test runs.

102. Move a table's rows and the links between tables into internal/rows, and walk every path through one per-step function, so Fake refuses a level carrying a repeat as the load check does.

Needs items 98 and 101. internal/rows takes the rows, their key and parent proofs, the pins, the row draws and the lookups, and owns the parent and child links. Each rows table holds the engine table that owns it as a payload of a type parameter, set when the rows table is built, so a step to a relative reaches its format and cells with no side map, the links have one writer, and internal/rows imports no engine type. The rows code reads checkName and the selector spelling from internal/grammar. The lookups reuse the weights sumWeights parsed; today builtLookup parses them again. Today pathCheck.walk and probePath are two loops over one rule for passing a choice, a table or a field, and they have drifted: probePath skips pathCheck.enter, so Fake("x.a") under "repeat":3 renders one draw where the README's Correlated fields section refuses it; the refusal owes a CHANGELOG.md entry. The shared step takes its state as parameters, as drawSteps does: one loop switching on a mode raised a repeat of a reference path from 66 to 106 allocations (decision "A path draws through its compiled steps"). Technical principle: DRY.

97. Move the seeded randomness and its {seq()} counters into internal/drawstate, built from a seed, and test which packages each package may import.

First of the restructure items 97 to 106, which give each value one writer a reader can name and move what stands alone into internal/; the decision "The template engine stays the root package until item 107, and items 97 to 103 move what stands alone into internal/" says why the engine stays. This item's first commit adds a test, using go/build, that lists each package's allowed imports; every later item extends it. New reads the system's entropy for an unseeded generator and hands the seed over, until item 89 moves that read into the CLI. newRand and the generator's rand field are renamed after the draw state, which holds the {seq()} counters as well as the randomness, and New's local rng stops shadowing the rng interface. A function module of item 77 reaches the randomness through an interface the root declares; the concrete state stays internal.

103. Move the folder walk and the reading of a data tree's JSON and TSV files into internal/datafiles, which hands the engine a reader for each table's rows.

Needs item 98. The folder walk, the hidden-file and empty-folder rules, reading a category's rows, and the check that every TSV is named move; the engine compiles each category as the walk hands it over, a table's rows are read through the reader only when its JSON names them, and errors keep their order.

98. Move how the template language is written — format tokens, paths and selectors, reference sigils, names and calc syntax — into internal/grammar.

Needs item 97. Pure code that reads strings: scanUnit, formatToken and parseFormat; the spelling half of path.go, splitPath through joinSegments; refShape; checkName; isTemplate; and the calc parser. parseFormat takes the lister of a builtin's operands as an argument, so the grammar imports no registry.

100. Move the builtins, with their checksums, layouts and transforms, into internal/builtinfunc, and check calc's operands where its template links.

Needs item 99. checkArgs drops its fields parameter: calc, the one builtin reading it, checks its operands where the template links, and a load with two mistakes reports the same one first as today. ibanArg joins the builtins, and callFn takes internal/drawstate's type.

106. Settle each record's shape when its template links, so Generator.records goes.

Needs item 105. Settling all 84 shipped record shapes took 0.09 ms on 2026-10-05, so the cache saves nothing. The error for FakeRecord on a node that is no record stays at call time. bindingOfWhole stops repeating a load-time search on every column of every record draw.

101. Set a table's path when it compiles, link a table family in one function, and label a cell's template from the walk, so no template points back at its table.

template.site serves only labels and the table-cell refusals at compile, so it goes and the walk names the label. setTablePaths and the write linkParent makes into another table's children become one builder; AGENTS.md's complexity rule, which names linkParent among the dispatches that stay whole, changes with it.

104. Create a name scope with its owner in one place, and hand a template's name reads to the checks as a returned value, not appended to its bindings.

The two-way link nameScope.owner ↔ template.ownNameScope is written by a third party, settle; resolveReads appends uses to a binding that only the load checks read.

79. Beside a --data-path, load in New the user's categories, the shipped ones they override or read, and the shipped ones whose reads reach an overridden one; load the rest on first reach.

Needs item 77, which makes an override fail unless it says it replaces.

The decision "With only the shipped set, a category loads on the first call reaching it; beside a --data-path, every category loads in New" parses the whole shipped set on every --data-path run, about 45 ms today and seconds once items 61 and 78 land. Goal 6 needs only the user's categories, the shipped ones they override, the shipped ones they read, and the shipped ones whose reads reach an overridden category, so the index would carry each category's reads.

99. Move DataType into internal/datatype, aliased by the root, and what a proof knows of a value, proven, into internal/proven.

Needs item 98. proven is keyed by DataType, and a package the root imports cannot import the root, so the type moves first. The root declares type DataType = datatype.DataType and its four constants by name, so the public spelling stays one; pkg.go.dev then lists the methods under the internal package, which the maintainer accepted on 2026-10-05. internal/datatype takes dataTypeNames and dataTypeNouns with the type. internal/proven takes proven and the arithmetic over it, combine, bounded, printing, shortestDecimals and the literal and number readers, and imports internal/grammar for the calc syntax combine reads; proving a node stays with the engine in valueproof.go.

105. Link each template in steps that each return what they build — its references, its bindings' heads and addressed keys, its compiled arms, its column read — so no step writes into what an earlier one built.

Needs item 104. linkBindings writes nameBinding.head and tail in linkRefs's first pass and linkName reads them in its second, so swapping the passes hands linkName a nil head. linkPasses does the same: linkColumnRead reads the arm.named that linkNames wrote and writes link.readsColumn into the link linkTemplate built, and checkNameReads reads the arms both filled. arm is filled in three places, compileFormat, compileArms and linkName, and splitArm runs before the link and again after it, so five readers of an earlier panel traced three phases. Technical principle: one owner per value.

58. Ship prebuilt binaries, a container image, and packages for Homebrew, Scoop and the biggest Linux package managers, so the CLI needs no Go.

GoReleaser attaches the binaries to the release the tag workflow publishes, and builds deb and rpm packages, an Alpine APK and an AUR package beside Homebrew and Scoop. A checkout build prints devel for --version; the binaries carry the stamped tag. v0.1.0 ships first, so it can be tested before it is packaged.

26. Spell sv_SE.personnummer with the + Skatteverket uses from the year the holder turns 100, judged by a date the caller gives.

The format hard-codes -, and its earliest birthdate, 1930-01-01, makes the oldest draws invalid from 2030. A system holding Swedish personnummer often breaks on the +, so a fixture carrying one is a valuable test. Whether a number takes + depends on the date it is read, and the decision "No builtin reads the clock, so a date is bounded by days, never by an age" forbids a builtin from reading that date off the clock. This item revises it: once the caller gives the date, an age is a bound, and the CLI's default date makes output change with the day it runs unless the flag is given. Do the first step before the rest:

• Explore how a caller passes input data, such as the date a number is read on, to a render: in the template, as a plain option, or both. Make the library require the date, as item 89 makes it require the seed, and let the CLI default it to the system's when its flag is absent. Bench the spelling; --now reads like the clock. Shape the input so it can later narrow the draws to adults, children, 65 and over, or a mix, and so let a test ask for a centenarian; narrowing itself waits for its own item.
• Draw birthdates back past 100 years before the given date, so a + can appear. Read in 2026, the oldest shipped birthdate is 96 years old, so no draw carries a + until 2030. Skatteverket's test series reaches back to 1890, with birth numbers 980/981 before 1900. Draw no birthdate after the given date.
• Weight the ages by the territory's population, so the share of + numbers follows its demography: research-age-bands.md.
• Let a data author's own category spell the separator too, through a builtin or a function a data module provides (item 77), and update the README's personnummer recipe and its "a day in 1930–2025" count.
• Rewrite the README's --seed and WithSeed rows to goal 10's wording, and name the new required option in the changelog: New breaks a second time here, after item 89, as the maintainer accepted.
• Research: sv_SE.samordningsnummer also hard-codes - and draws from 1930. Check whether Lag (2022:1697) om samordningsnummer gives it the same +; folkbokföringslagen 18 § states the rule for personnummer only.

81. Refuse at load every calc operand not proven numeric and every divisor not proven nonzero, in a string column too.

The decision "A constant zero divisor is a load error; in a string column a divisor that is not constant prints Inf" lets {calc(a/(b*c))} with b fixed at "0" write Inf into every row. An operand that is sometimes not a number prints NaN. Both work against goals 6.1 and 4. valueproof.go already proves a typed column's divisor nonzero.

36. Report every mistake a load finds in one error, as the decision "A load reports every mistake at once" states.

New and NewTemplate stop at the first, so data holding two mistakes takes two runs to fix. Split it into items before starting, one of them the shape a Go caller iterates and the CLI prints, and the order of an inline template's mistakes, which name no path; reword the README's "New refuses a mistake in the data" to every mistake.

88. Add a 12-digit YYYYMMDDNNNC form of sv_SE.personnummer and sv_SE.samordningsnummer, the form Skatteverket's testpersonnummer series and many systems store.

A system that stores the 12-digit form never meets the +, so it needs a fixture in that form.

41. Key every table by one key column, as the decision "A table selects by one key column, a code, never a free-form name" states.

geo.SE.municipality[Lund] and misc.territory[Sweden] select a row today. Steps:

• Have a selector that misses name the key of every row whose cell spells it, matched without case, else say the table selects by its key: misc.territory[Sweden] and misc.territory[se] name [SE], misc.protocol[tcp] its key, and misc.loglevel[Error] [err].
• Delete the name option and the load checks it carries, and have New refuse a table still carrying name, naming key.
• Key misc.loglevel on keyword, and geo.SE.locality on the integer data-import/geo-se.py assigns as the decision states, linking street and postal-code by it.
• Drop key from last-name and sv_SE.title, and re-pin testdata/shipped_shape.txt.
• Leave no selection by name in README.md, CHANGELOG.md, docs/ or --help.

52. Name the file a link error comes from beside its category path, sub.x (/d/a/sub/x.json): ….

With several --data-path layers the author has to work out which directory won, while a parse error on the same file names it.

28. Accept a middle name, and draw a personnummer whose sex matches a sex selected through a named pick.

Today personnummer draws its own sex, so a name and a number agree only through the README Data section's template, which reads both through one bound sex.

24. Stop misc.territory[EH].tld rendering .eh, the one shipped TLD misc.tld does not hold.

ISO 3166 reserves it for Western Sahara and the root zone has never been delegated it, so no resolver answers for it.

92. Name the hyphenated field in a calc's refusal, and say to rename it: today {calc(postal-code * 2)} reports no field "postal".

A hyphen is always subtraction in a calc, and the shipped data has hyphenated fields (postal-code and street-number in geo/SE/address). The refusal names the first fragment, not the field the author meant.

53. Let a table column carry a datatype, so --format json writes "safe": true and --format sql a boolean.

Today only a JSON field takes one, so misc.httpmethod's booleans are typed in Go and text everywhere else. Typing a shipped column changes what json and sql write, so the capability is a minor and applying it to misc.httpmethod is a major.

44. Have misc.tld[se] select the row keyed .se, or have its miss name [.se].

The decision "misc.tld keys carry the leading dot, where other tables key on a bare code" leaves misc.tld[se] missing today.

54. Read the tag through git/ref/tags/{tag} in publish_release.py.

GitHub answers tags/{tag} with 404 whatever exists, so the burnt-version guard never fires and a release lands on a tag already pointing at another commit.

31. Rename misc.territory.country to sovereign.

It holds a code, and country collides with the misc.country path it replaced.

20. Weight sv_SE.sex and en_US.sex by bearers, as the README's Data section says they are.

Neither names a weight, so a bare sex draws evenly.

50. Reword prove's refusal of a typed column reading a row, {/region}.

Say the format is the table's own (region's format "{name}"), name the read to write, {/region.<column>} with its columns, and stop calling a one-column format, {code}, composed text.

17. Give every shipped category a column for each part its format composes, and one record shape across the national ids; re-pin the shape.

misc.uuid gains variant, for one.

29. Let a path go from a selected row into the template beside its family: geo.US.locality[1714000].address.

Require the path step to reach a sibling category.

42. Refuse a struct tag's datatype naming the Go type that sets it before proving its values, as the README's Library section promises.

datatype: boolean over {int(1,2)} on an int field answers prints an integer, not a boolean.

22. Give url and email a path that draws only domains nobody can register, keeping the wide set as the default.

17 of the 40 distinct ones shipped today sit on .se, .nu, .io and .co, which anyone may register, and only RFC 2606's example.com, .net, .org, .test, .example, .invalid and .localhost provably reach nothing.

46. Report the same error every load for a table with two bad options, and for a folder with two unnamed rows files.

readTableOptions and loadDir return on the first in Go's map order.

107. Move the template engine into internal/, leaving the root the public API and its options.

Needs item 5. The engine returns column values and the root builds Record. Revises the decision "The template engine stays the root package until item 107, and items 97 to 103 move what stands alone into internal/", and, if the vocabulary moves, "The vocabulary sits below doc.go's package clause, not in the package doc".

94. Refuse a name whose every read passes one deeper level, naming the binding of that level: {place as p}{p.geo.town.name} {p.geo.town.zip} is {place.geo.town as t}{t.name} {t.zip}.

Both spellings load and draw alike, against goal 5.7. Widen the read-once refusal in namefence.go to the longest prefix every read of a name shares.

14. Spell misc.creditcard's digit runs {digits(n)}.

A "repeat": 14 over {digits(1)} draws every 14-digit run with the odds {digits(14)} does. Both load, since neither has a part that changes nothing; the shipped data writes the obvious one. Re-pin seeded output in its own commit.

38. Compare calcParser.binary's operator as a rune.

byte(p.rs[p.pos]) reads U+012B ī as +, so {calc(a ī b)} compiles as a + b.

45. Name the node a selector follows in stepInto's refusal.

sv_SE.person[1].first answers 1 is not a table.

49. Report a CRLF rows file holding only its header as having no rows.

parseRows answers "line 2 is empty".

13. Place xlsx cells by their r reference in data-import/xlsx.py.

A sheet omitting an empty cell shifts every later column left.

39. Stop the columnKinds suggestion naming a field's own kind or a narrower one.

An int64 or float64 field unproven in range is told to become itself, and a uint64 one to become int64.

51. Spell a table one way across the errors that name it.

pinRow names t.path and mustRow panics with t.category, so one table is territory and misc.territory, and the short spelling names no file where two folders hold that name.

10. Test that every node kind reaches each switch over node kinds.

Today nine, from render to columnItems, must agree, and only render and renderEdges say so.

11. Test that every geo tree holds the five table names and the address columns that port across countries.

Nothing checks it, and a new country breaks it silently.

40. Parse defaultTable's path with the library's grammar.

The CLI counts brackets of its own, so a change to the selector grammar desyncs the default --table silently.

86. Read both en_US.phone formats' area codes from one category, as their exchange reads en_US.phone-exchange.

Both phone formats carry the same 21-code area list, so an edit to one copy can miss the other.

23. Give every other shipped category that could reach something real a path that never does.

phone draws live PTS and NANP ranges — PTS's five fiction series are the Swedish inert set, sourced in research-sources-se.md, and the NANP one still wants a source — and bankgiro, plusgiro and routing draw live prefixes.

75. Run every README sh, go and text example as a test, and compare each "Renders" line to a seeded render.

readme_test.go loads and renders each json block, but runs no sh example (CLI, Records, Table, Linked tables), no go example (Library) and no text block of error text, and compares no "Renders e.g." output, so goal 12.2 is not met.

47. Refuse a category naming a hidden rows file, "rows": ".x.tsv", as a rows file that is not there.

loadDir indexes hidden TSVs and skips them in two places, so one loads where its comment says a hidden file is never data.

72. Fail the merge gate when test coverage falls below the last recorded figure.

technical-principles.md holds that test coverage should not decline. docker compose run --rm cover prints the figure, and neither the Dockerfile gate nor .github/workflows/test.yml checks it.

43. Call templateError a compile failure in its doc.

Its doc says render failure, and it wraps what NewTemplate and NewRecordTemplate refuse.

95. Hold a struct's columns and the field each fills in one slice.

structShape.columns and structShape.fieldIndexes pair up by index alone, against the technical principle "one owner per value".

56. Build on a manual run of test.yml.

workflow_dispatch leaves github.event.before empty, so the diff compares HEAD with itself and skips docker build.

63. Pair a street with its exact postnummer.

Needs an application to Lantmäteriet; today a street goes to the nearest postal code centroid. It rewrites shipped rows, so it is a major once 1.0 is cut and a minor before that.

62. Add {btc()} and {eth()}.

They need sha256 and keccak for Base58Check and EIP-55.

59. Promise in Generator's godoc that its renders run one at a time.

A caller wanting parallel throughput then makes one generator per goroutine.

65. Hold every change AGENTS.md says owes a CHANGELOG.md entry to one in CI.

The check covers data and testdata/shipped_shape.txt alone, where AGENTS.md adds a flag, an exit code, an exported name, a fence, a builtin and the lowest Go.

66. Cut the README's Layout block to the lines that say what a file name cannot.

calc.go, doc.go and cmd/fejkdata/ restate their names.

67. Cut AGENTS.md to the rules only it states, and explain every term its comprehension rule uses.

The gh rule opens by restating the decision "GitHub is canonical, and the module path names it", a second copy that drifts. The comprehension rule packs the gate, its exceptions, the round and the at-or-above-7.0 regime into one line, and uses "depth 1", "nine-seat", "four-seat" and "answers it in one run" without saying what they mean.

64. Give every entry in docs/decisions.md the goal it serves, its date, who made it and the premise it rests on.

Propose a goal for an entry that serves none.

68. Make gitea.larvit.se/larvit/fejkdata a pull mirror of GitHub.

Gitea converts a repository to a mirror only by re-creating it, so until that runs the copy there is a second owner of one history.

69. Announce v1.0.0 where a developer choosing a fake-data tool already reads, with a README first screen for someone deciding in a minute.

The human cuts v1.0.0 once the shipped data is in its record shape and one full minor has shipped with no breaking change, per the README's Versioning table; pairing a street with its exact postnummer rewrites shipped rows, so a minor with no breaking change follows it first.