{ "id": "payroll", "title": "Payroll and HR", "summary": "UK payroll for a small employer: PAYE tax, National Insurance, pensions, student loans and statutory pay into a payslip, plus holiday, notice and absence rules.", "synonyms": [ "payroll", "payslips", "pay slips", "wages", "salaries", "paye", "hr", "human resources", "staff pay", "employee pay", "people management", "holiday tracker" ], "apps": [ "payroll app", "payroll system for a small business", "payslip generator", "hr system", "staff holiday and absence tracker", "employee management software" ], "language": "typescript", "includes": [ "money-basics", "dates-basics", "validation-basics" ], "includedBy": [], "caveats": [ "UK only: PAYE, National Insurance, student loans, statutory pay and pensions follow HMRC and UK employment rules for each tax year.", "Not payroll or legal advice. Run the figures past HMRC's calculators or a payroll professional before paying people from them." ], "sections": [ { "key": "employees", "title": "Employee records", "purpose": "Check the identifiers and dates an employee record holds.", "from": "payroll", "members": [ { "id": "validation.uk-ni-number", "tier": "core", "why": "Checks a National Insurance number's format and HMRC's disallowed prefixes.", "section": "employees", "from": "payroll", "version": "2.0.0", "summary": "Check a UK National Insurance number's format and HMRC's disallowed prefix letters, and normalise it.", "status": "stable", "license": "NOASSERTION", "languages": [ "typescript", "python", "rust" ], "available": true, "group": false, "functions": [ "validateUkNiNumber" ], "signatures": [ "export function validateUkNiNumber(value: string): UkNiNumber" ], "reference": "import { validateUkNiNumber } from \"#fune/validation.uk-ni-number@^2\";", "url": "http://www.functionalweave.com/functions/validation.uk-ni-number" }, { "id": "payroll.tax-code-parse", "tier": "core", "why": "Reads a PAYE tax code (1257L, K475, BR, S/C prefixes, W1/M1) into its allowance and flags.", "section": "employees", "from": "payroll", "version": "1.0.2", "summary": "Parse a UK PAYE tax code (1257L, K475, BR, D0, NT, 0T, S and C prefixes, W1/M1/X) into its allowance and flags.", "status": "unreviewed", "license": "NOASSERTION", "languages": [ "typescript", "python", "rust" ], "available": true, "group": false, "functions": [ "parseTaxCode" ], "signatures": [ "export function parseTaxCode(code: string): TaxCode" ], "reference": "import { parseTaxCode } from \"#fune/payroll.tax-code-parse@^1\";", "url": "http://www.functionalweave.com/functions/payroll.tax-code-parse" }, { "id": "dates.age", "tier": "core", "why": "Age on a date, which decides minimum wage bands and NI category.", "section": "employees", "from": "payroll", "version": "1.0.0", "summary": "Age in whole years on a given date, with 29 February birthdays ageing on 1 March in other years.", "status": "stable", "license": "NOASSERTION", "languages": [ "typescript", "python", "rust" ], "available": true, "group": false, "functions": [ "age" ], "signatures": [ "export function age(birthDate: string, onDate: string): number" ], "reference": "import { age } from \"#fune/dates.age@^1\";", "url": "http://www.functionalweave.com/functions/dates.age" }, { "id": "hr.length-of-service", "tier": "optional", "why": "Continuous service in years, months and days, for notice, redundancy and benefits.", "section": "employees", "from": "payroll", "version": "1.0.0", "summary": "Continuous service between two dates in completed years, months and days, counting both end dates.", "status": "stable", "license": "NOASSERTION", "languages": [ "typescript", "python", "rust" ], "available": true, "group": false, "functions": [ "lengthOfService" ], "signatures": [ "export function lengthOfService(startDate: string, endDate: string): ServiceLength" ], "reference": "import { lengthOfService } from \"#fune/hr.length-of-service@^1\";", "url": "http://www.functionalweave.com/functions/hr.length-of-service" } ], "gaps": [ { "key": "starter-leaver-forms", "text": "Starter checklists, P45 and P60 documents: caps gives the figures, not the forms.", "section": "employees", "from": "payroll" } ] }, { "key": "periods", "title": "Pay periods", "purpose": "Put each pay date into the right PAYE period.", "from": "payroll", "members": [ { "id": "payroll.tax-period", "tier": "core", "why": "The tax week, tax month and period number a pay date falls in, weeks 53, 54 and 56 included.", "section": "periods", "from": "payroll", "version": "1.0.1", "summary": "The UK PAYE tax week, tax month and payroll period number that a pay date falls in, weeks 53, 54 and 56 included.", "status": "unreviewed", "license": "NOASSERTION", "languages": [ "typescript", "python", "rust" ], "available": true, "group": false, "functions": [ "taxPeriod" ], "signatures": [ "export function taxPeriod(payDate: string, frequency: PayFrequency): TaxPeriod" ], "reference": "import { taxPeriod } from \"#fune/payroll.tax-period@^1\";", "url": "http://www.functionalweave.com/functions/payroll.tax-period" }, { "id": "dates.uk-tax-year", "tier": "core", "why": "Which tax year (6 April to 5 April) a pay date belongs to.", "section": "periods", "from": "payroll", "version": "1.0.0", "summary": "The UK personal tax year containing a date: 6 April to 5 April, with HMRC's label.", "status": "stable", "license": "NOASSERTION", "languages": [ "typescript", "python", "rust" ], "available": true, "group": false, "functions": [ "ukTaxYear" ], "signatures": [ "export function ukTaxYear(iso: string): UkTaxYear" ], "reference": "import { ukTaxYear } from \"#fune/dates.uk-tax-year@^1\";", "url": "http://www.functionalweave.com/functions/dates.uk-tax-year" } ], "gaps": [] }, { "key": "gross-pay", "title": "Gross pay", "purpose": "Work out what each employee earned in the period.", "from": "payroll", "members": [ { "id": "payroll.pro-rata-salary", "tier": "core", "why": "Salary for part of a period (joiners, leavers) and for part-time hours.", "section": "gross-pay", "from": "payroll", "version": "1.0.1", "summary": "Salary for part of a pay period and for part-time hours, by calendar days or working days, rounded once.", "status": "unreviewed", "license": "NOASSERTION", "languages": [ "typescript", "python", "rust" ], "available": true, "group": false, "functions": [ "proRataSalary" ], "signatures": [ "export function proRataSalary(periodSalary: Money, fteBasisPoints: number, periodStart: string, periodEnd: string, workedFrom: string, workedTo: string, method: ProRataMethod, holidays: readonly string[]): ProRata" ], "reference": "import { proRataSalary } from \"#fune/payroll.pro-rata-salary@^1\";", "url": "http://www.functionalweave.com/functions/payroll.pro-rata-salary" }, { "id": "payroll.overtime", "tier": "optional", "why": "Overtime pay in multiplier bands: time and a half after 40 hours, double time.", "section": "gross-pay", "from": "payroll", "version": "1.0.1", "summary": "Pay for the time worked in a period split into multiplier bands: basic, time and a half after 40 hours, double time.", "status": "unreviewed", "license": "NOASSERTION", "languages": [ "typescript", "python", "rust" ], "available": true, "group": false, "functions": [ "overtimePay" ], "signatures": [ "export function overtimePay(minutesWorked: number, hourlyRate: Money, bands: readonly OvertimeBand[]): OvertimePay" ], "reference": "import { overtimePay } from \"#fune/payroll.overtime@^1\";", "url": "http://www.functionalweave.com/functions/payroll.overtime" }, { "id": "payroll.minimum-wage-check", "tier": "optional", "why": "Checks pay for the period against the minimum or living wage for the worker's age.", "section": "gross-pay", "from": "payroll", "version": "1.0.1", "summary": "Check pay for a pay reference period against the minimum or living wage for age and apprenticeship.", "status": "unreviewed", "license": "NOASSERTION", "languages": [ "typescript", "python", "rust" ], "available": true, "group": false, "functions": [ "minimumWageCheck" ], "signatures": [ "export function minimumWageCheck(pay: Money, minutesWorked: number, birthDate: string, periodStart: string, apprenticeshipStart: string | null): MinimumWageCheck" ], "reference": "import { minimumWageCheck } from \"#fune/payroll.minimum-wage-check@^1\";", "url": "http://www.functionalweave.com/functions/payroll.minimum-wage-check" }, { "id": "charity.payroll-giving", "tier": "optional", "why": "Payroll Giving donations taken before PAYE, and the tax they save.", "section": "gross-pay", "from": "payroll", "version": "1.0.0", "summary": "UK Payroll Giving for one pay period: the donation comes off pay before PAYE, and the tax it saves the employee.", "status": "stable", "license": "NOASSERTION", "languages": [ "typescript", "python", "rust" ], "available": true, "group": false, "functions": [ "payrollGiving" ], "signatures": [ "export function payrollGiving(taxCode: string, frequency: PayFrequency, period: number, pay: Money, donation: Money, previousPayToDate: Money, previousTaxToDate: Money, payDate: string): PayrollGiving" ], "reference": "import { payrollGiving } from \"#fune/charity.payroll-giving@^1\";", "url": "http://www.functionalweave.com/functions/charity.payroll-giving" } ], "gaps": [] }, { "key": "deductions", "title": "Tax and deductions", "purpose": "Take tax, National Insurance, pension and loans off the gross, and give the payslip.", "from": "payroll", "members": [ { "id": "payroll.gross-to-net", "tier": "core", "why": "The whole payslip for one period: gross, pension, PAYE, NI, student loans and net pay.", "section": "deductions", "from": "payroll", "version": "1.0.1", "summary": "A UK payslip for one pay period: gross pay, pension, PAYE tax, National Insurance, student loans and net pay.", "status": "unreviewed", "license": "NOASSERTION", "languages": [ "typescript", "python", "rust" ], "available": true, "group": false, "functions": [ "grossToNet" ], "signatures": [ "export function grossToNet(input: PayslipInput): Payslip" ], "reference": "import { grossToNet } from \"#fune/payroll.gross-to-net@^1\";", "url": "http://www.functionalweave.com/functions/payroll.gross-to-net" }, { "id": "payroll.income-tax", "tier": "core", "why": "PAYE income tax for one period, cumulative or week 1/month 1, by HMRC's tax tables.", "section": "deductions", "from": "payroll", "version": "1.0.2", "summary": "PAYE income tax for one pay period from a tax code, cumulative or week 1/month 1, by HMRC's tax table routines.", "status": "unreviewed", "license": "NOASSERTION", "languages": [ "typescript", "python", "rust" ], "available": true, "group": false, "functions": [ "incomeTax" ], "signatures": [ "export function incomeTax(taxCode: string, frequency: PayFrequency, period: number, pay: Money, previousPayToDate: Money, previousTaxToDate: Money, payDate: string): IncomeTax" ], "reference": "import { incomeTax } from \"#fune/payroll.income-tax@^1\";", "url": "http://www.functionalweave.com/functions/payroll.income-tax" }, { "id": "payroll.national-insurance", "tier": "core", "why": "Employee and employer Class 1 NICs by category letter for one payment.", "section": "deductions", "from": "payroll", "version": "1.0.2", "summary": "Employee and employer Class 1 National Insurance for one payment by category letter, exact percentage method.", "status": "unreviewed", "license": "NOASSERTION", "languages": [ "typescript", "python", "rust" ], "available": true, "group": false, "functions": [ "nationalInsurance" ], "signatures": [ "export function nationalInsurance(earnings: Money, category: string, frequency: PayFrequency, payDate: string, director: DirectorNi | null): NationalInsurance" ], "reference": "import { nationalInsurance } from \"#fune/payroll.national-insurance@^1\";", "url": "http://www.functionalweave.com/functions/payroll.national-insurance" }, { "id": "payroll.pension-auto-enrolment", "tier": "core", "why": "Auto-enrolment pension: qualifying earnings and employee and employer contributions.", "section": "deductions", "from": "payroll", "version": "1.0.2", "summary": "Workplace pension contributions for one pay period: qualifying earnings band, employee and employer shares, tax relief.", "status": "unreviewed", "license": "NOASSERTION", "languages": [ "typescript", "python", "rust" ], "available": true, "group": false, "functions": [ "pensionContributions" ], "signatures": [ "export function pensionContributions(earnings: Money, frequency: PayFrequency, scheme: PensionScheme, payDate: string): PensionContributions" ], "reference": "import { pensionContributions } from \"#fune/payroll.pension-auto-enrolment@^1\";", "url": "http://www.functionalweave.com/functions/payroll.pension-auto-enrolment" }, { "id": "payroll.student-loan", "tier": "core", "why": "Student and postgraduate loan deductions by plan.", "section": "deductions", "from": "payroll", "version": "1.0.2", "summary": "Student loan or postgraduate loan deduction from one period's pay, by plan, rounded down to whole pounds.", "status": "unreviewed", "license": "NOASSERTION", "languages": [ "typescript", "python", "rust" ], "available": true, "group": false, "functions": [ "studentLoan" ], "signatures": [ "export function studentLoan(earnings: Money, plan: StudentLoanPlan, frequency: PayFrequency, payDate: string): Money" ], "reference": "import { studentLoan } from \"#fune/payroll.student-loan@^1\";", "url": "http://www.functionalweave.com/functions/payroll.student-loan" }, { "id": "payroll.net-to-gross", "tier": "optional", "why": "The gross pay that gives a target net pay, for agreed-net payments.", "section": "deductions", "from": "payroll", "version": "1.0.2", "summary": "The gross pay that gives at least a target net pay in one UK pay period, found by a deterministic search.", "status": "unreviewed", "license": "NOASSERTION", "languages": [ "typescript", "python", "rust" ], "available": true, "group": false, "functions": [ "netToGross" ], "signatures": [ "export function netToGross(targetNet: Money, input: PayslipInput): Payslip" ], "reference": "import { netToGross } from \"#fune/payroll.net-to-gross@^1\";", "url": "http://www.functionalweave.com/functions/payroll.net-to-gross" }, { "id": "fleet.company-car-bik", "tier": "optional", "why": "Company car benefit in kind for the tax year, for P11D or payrolled benefits.", "section": "deductions", "from": "payroll", "version": "1.0.2", "summary": "UK company car benefit in kind: appropriate percentage by CO2 and electric range, car and fuel benefit for a tax year.", "status": "unreviewed", "license": "NOASSERTION", "languages": [ "typescript", "python", "rust" ], "available": true, "group": false, "functions": [ "companyCarBik" ], "signatures": [ "export function companyCarBik(listPrice: Money, capitalContributions: Money, co2: number, electricRangeMiles: number, dieselSupplement: boolean, firstRegistered: string, onDate: string, unavailableDays: number, privateUseContributions: Money, freeFuel: boolean): CompanyCarBik" ], "reference": "import { companyCarBik } from \"#fune/fleet.company-car-bik@^1\";", "url": "http://www.functionalweave.com/functions/fleet.company-car-bik" }, { "id": "fleet.mileage-allowance", "tier": "optional", "why": "Approved mileage allowance payments for staff using their own vehicle: tax-free and taxable parts.", "section": "deductions", "from": "payroll", "version": "1.0.2", "summary": "HMRC approved mileage allowance payments for an employee's own vehicle: tax-free amount, taxable excess or relief.", "status": "stable", "license": "NOASSERTION", "languages": [ "typescript", "python", "rust" ], "available": true, "group": false, "functions": [ "mileageAllowance" ], "signatures": [ "export function mileageAllowance(vehicle: MileageVehicle, previousMiles: number, miles: number, passengerMiles: number, paid: Money, passengerPaid: Money, onDate: string): MileageAllowance" ], "reference": "import { mileageAllowance } from \"#fune/fleet.mileage-allowance@^1\";", "url": "http://www.functionalweave.com/functions/fleet.mileage-allowance" } ], "gaps": [ { "key": "rti-submission", "text": "Sending FPS and EPS returns to HMRC under Real Time Information: the XML, the gateway and the credentials are yours.", "section": "deductions", "from": "payroll" }, { "key": "pension-provider-files", "text": "Contribution files for pension providers (NEST, The People's Pension) and enrolment letters.", "section": "deductions", "from": "payroll" } ] }, { "key": "statutory-pay", "title": "Statutory pay", "purpose": "Pay what the law requires while an employee is off sick or on family leave.", "from": "payroll", "members": [ { "id": "payroll.statutory-sick-pay", "tier": "core", "why": "SSP for sickness spells: waiting days, linked periods, the 28-week limit and the rate by date.", "section": "statutory-pay", "from": "payroll", "version": "1.0.1", "summary": "UK Statutory Sick Pay for sickness spells: waiting days, 8-week linking, 28-week limit and the rate by date.", "status": "unreviewed", "license": "NOASSERTION", "languages": [ "typescript", "python", "rust" ], "available": true, "group": false, "functions": [ "statutorySickPay" ], "signatures": [ "export function statutorySickPay(periods: readonly SicknessPeriod[], qualifyingWeekdays: readonly number[], normalWeeklyEarnings: Money): SickPay" ], "reference": "import { statutorySickPay } from \"#fune/payroll.statutory-sick-pay@^1\";", "url": "http://www.functionalweave.com/functions/payroll.statutory-sick-pay" }, { "id": "payroll.statutory-maternity-pay", "tier": "optional", "why": "SMP eligibility and its 39 weekly amounts.", "section": "statutory-pay", "from": "payroll", "version": "1.0.1", "summary": "UK Statutory Maternity Pay: LEL eligibility and 39 weekly amounts, 90% then the lower of 90% or the flat rate.", "status": "unreviewed", "license": "NOASSERTION", "languages": [ "typescript", "python", "rust" ], "available": true, "group": false, "functions": [ "statutoryMaternityPay" ], "signatures": [ "export function statutoryMaternityPay(averageWeeklyEarnings: Money, dueDate: string, payStart: string): MaternityPay" ], "reference": "import { statutoryMaternityPay } from \"#fune/payroll.statutory-maternity-pay@^1\";", "url": "http://www.functionalweave.com/functions/payroll.statutory-maternity-pay" } ], "gaps": [] }, { "key": "leave", "title": "Holidays and absence", "purpose": "Track holiday entitlement and absence.", "from": "payroll", "members": [ { "id": "payroll.holiday-entitlement", "tier": "core", "why": "Statutory holiday: 5.6 weeks capped at 28 days, pro-rated, or 12.07% for irregular hours.", "section": "leave", "from": "payroll", "version": "1.0.1", "summary": "UK statutory holiday: 5.6 weeks capped at 28 days and pro-rated, or 12.07% accrual for irregular hours.", "status": "unreviewed", "license": "NOASSERTION", "languages": [ "typescript", "python", "rust" ], "available": true, "group": false, "functions": [ "holidayEntitlement" ], "signatures": [ "export function holidayEntitlement(worker: HolidayWorker, leaveYearStart: string): HolidayEntitlement" ], "reference": "import { holidayEntitlement } from \"#fune/payroll.holiday-entitlement@^1\";", "url": "http://www.functionalweave.com/functions/payroll.holiday-entitlement" }, { "id": "payroll.holiday-pay-accrual", "tier": "optional", "why": "Holiday pay: 12.07% rolled-up, or a week's pay averaged over 52 paid weeks.", "section": "leave", "from": "payroll", "version": "1.0.1", "summary": "UK holiday pay: 12.07% rolled-up holiday pay, or a week's pay averaged over the last 52 paid weeks.", "status": "unreviewed", "license": "NOASSERTION", "languages": [ "typescript", "python", "rust" ], "available": true, "group": false, "functions": [ "holidayPay" ], "signatures": [ "export function holidayPay(method: HolidayPayMethod, periodPay: Money, weeklyPay: readonly Money[], onDate: string): HolidayPay" ], "reference": "import { holidayPay } from \"#fune/payroll.holiday-pay-accrual@^1\";", "url": "http://www.functionalweave.com/functions/payroll.holiday-pay-accrual" }, { "id": "hr.absence-bradford-factor", "tier": "optional", "why": "Bradford factor from absence spells, to flag frequent short absences.", "section": "leave", "from": "payroll", "version": "1.0.0", "summary": "Bradford factor for a set of absence spells: spells squared times total days, which weights frequent short absences.", "status": "stable", "license": "NOASSERTION", "languages": [ "typescript", "python", "rust" ], "available": true, "group": false, "functions": [ "bradfordFactor" ], "signatures": [ "export function bradfordFactor(spellDays: readonly number[]): BradfordFactor" ], "reference": "import { bradfordFactor } from \"#fune/hr.absence-bradford-factor@^1\";", "url": "http://www.functionalweave.com/functions/hr.absence-bradford-factor" } ], "gaps": [ { "key": "leave-requests", "text": "Requesting and approving leave, team calendars and clashes.", "section": "leave", "from": "payroll" } ] }, { "key": "leavers", "title": "Leaving", "purpose": "Work out what a leaver is owed.", "from": "payroll", "members": [ { "id": "payroll.notice-period", "tier": "optional", "why": "Statutory minimum notice from length of service.", "section": "leavers", "from": "payroll", "version": "1.0.1", "summary": "Statutory minimum notice in weeks from continuous service: one week per year from two years, capped at twelve.", "status": "unreviewed", "license": "NOASSERTION", "languages": [ "typescript", "python", "rust" ], "available": true, "group": false, "functions": [ "statutoryNotice" ], "signatures": [ "export function statutoryNotice(startDate: string, noticeDate: string): StatutoryNotice" ], "reference": "import { statutoryNotice } from \"#fune/payroll.notice-period@^1\";", "url": "http://www.functionalweave.com/functions/payroll.notice-period" }, { "id": "payroll.redundancy-pay", "tier": "optional", "why": "Statutory redundancy pay from age, service and a capped week's pay.", "section": "leavers", "from": "payroll", "version": "1.0.1", "summary": "Statutory redundancy pay from age, completed years of service (at most 20) and a week's pay capped by date.", "status": "unreviewed", "license": "NOASSERTION", "languages": [ "typescript", "python", "rust" ], "available": true, "group": false, "functions": [ "statutoryRedundancyPay" ], "signatures": [ "export function statutoryRedundancyPay(birthDate: string, startDate: string, relevantDate: string, weeklyPay: Money): RedundancyPay" ], "reference": "import { statutoryRedundancyPay } from \"#fune/payroll.redundancy-pay@^1\";", "url": "http://www.functionalweave.com/functions/payroll.redundancy-pay" } ], "gaps": [] }, { "key": "payments", "title": "Paying staff", "purpose": "Get net pay into employees' accounts on payday.", "from": "payroll", "members": [ { "id": "banking.bacs-processing-date", "tier": "optional", "why": "When to submit a Bacs payment run so it arrives on payday, skipping weekends and bank holidays.", "section": "payments", "from": "payroll", "version": "1.0.0", "summary": "Bacs three-day cycle: input, processing and entry (arrival) dates for a submission, skipping weekends and bank holidays.", "status": "stable", "license": "NOASSERTION", "languages": [ "typescript", "python", "rust" ], "available": true, "group": false, "functions": [ "bacsProcessingDates" ], "signatures": [ "export function bacsProcessingDates(submissionIso: string, afterCutoff: boolean): BacsCycle" ], "reference": "import { bacsProcessingDates } from \"#fune/banking.bacs-processing-date@^1\";", "url": "http://www.functionalweave.com/functions/banking.bacs-processing-date" } ], "gaps": [ { "key": "bacs-files", "text": "Writing the Bacs Standard 18 payment file or a bank's bulk-payment CSV.", "section": "payments", "from": "payroll" } ] }, { "key": "amounts", "title": "Amounts", "purpose": "Hold money as currency-tagged integer minor units and do plain arithmetic on it safely.", "from": "money-basics", "members": [ { "id": "money.amount", "tier": "core", "why": "The Money type ({ minor, currency }) every other money capability takes and returns.", "section": "amounts", "from": "money-basics", "version": "1.0.2", "summary": "A currency-tagged monetary amount held in integer minor units.", "status": "stable", "license": "NOASSERTION", "languages": [ "typescript", "python", "rust" ], "available": true, "group": false, "functions": [ "money" ], "signatures": [ "export function money(minor: number, currency: string): Money" ], "reference": "import { money } from \"#fune/money.amount@^1\";", "url": "http://www.functionalweave.com/functions/money.amount" }, { "id": "money.add", "tier": "core", "why": "Adds and subtracts amounts, refusing to mix currencies by accident.", "section": "amounts", "from": "money-basics", "version": "1.0.1", "summary": "Add, subtract and negate monetary amounts, refusing to mix currencies.", "status": "stable", "license": "NOASSERTION", "languages": [ "typescript", "python", "rust" ], "available": true, "group": false, "functions": [ "addMoney" ], "signatures": [ "export function addMoney(a: Money, b: Money): Money" ], "reference": "import { addMoney } from \"#fune/money.add@^1\";", "url": "http://www.functionalweave.com/functions/money.add" }, { "id": "money.sum", "tier": "core", "why": "Totals a list of amounts, with an explicit currency for an empty list.", "section": "amounts", "from": "money-basics", "version": "1.0.1", "summary": "Total a list of monetary amounts, with an explicit currency for the empty case.", "status": "stable", "license": "NOASSERTION", "languages": [ "typescript", "python", "rust" ], "available": true, "group": false, "functions": [ "sumMoney" ], "signatures": [ "export function sumMoney(amounts: readonly Money[], currency: string): Money" ], "reference": "import { sumMoney } from \"#fune/money.sum@^1\";", "url": "http://www.functionalweave.com/functions/money.sum" }, { "id": "money.compare", "tier": "core", "why": "Compares, mins, maxes and clamps amounts of one currency without unwrapping them.", "section": "amounts", "from": "money-basics", "version": "2.0.0", "summary": "Compare two amounts of one currency, refusing to compare across currencies; min, max and clamp too.", "status": "stable", "license": "NOASSERTION", "languages": [ "typescript", "python", "rust" ], "available": true, "group": true, "functions": [ "compareMoney", "minMoney", "maxMoney", "clampMoney" ], "signatures": [ "export function compareMoney(a: Money, b: Money): number", "export function minMoney(a: Money, b: Money): Money", "export function maxMoney(a: Money, b: Money): Money", "export function clampMoney(amount: Money, min: Money, max: Money): Money" ], "reference": "import { compareMoney, minMoney, maxMoney, clampMoney } from \"#fune/money.compare@^2\";", "url": "http://www.functionalweave.com/functions/money.compare" } ], "gaps": [] }, { "key": "rates", "title": "Rates and rounding", "purpose": "Apply percentages and divide amounts with the rounding stated, never a float.", "from": "money-basics", "members": [ { "id": "money.apply-rate", "tier": "core", "why": "Applies a basis-point rate (VAT, discount, commission) to an amount with explicit rounding.", "section": "rates", "from": "money-basics", "version": "1.0.1", "summary": "Apply a rate expressed in basis points to a monetary amount, with an explicit rounding mode.", "status": "stable", "license": "NOASSERTION", "languages": [ "typescript", "python", "rust" ], "available": true, "group": false, "functions": [ "applyRate" ], "signatures": [ "export function applyRate(amount: Money, basisPoints: number, mode: RoundingMode): Money" ], "reference": "import { applyRate } from \"#fune/money.apply-rate@^1\";", "url": "http://www.functionalweave.com/functions/money.apply-rate" }, { "id": "math.round-div", "tier": "core", "why": "Integer division with a named rounding mode, for any money maths the others do not cover.", "section": "rates", "from": "money-basics", "version": "1.0.0", "summary": "Integer division with an explicit rounding mode, for money arithmetic that must not drift.", "status": "stable", "license": "NOASSERTION", "languages": [ "typescript", "python", "rust" ], "available": true, "group": false, "functions": [ "roundDiv" ], "signatures": [ "export function roundDiv(numerator: number, denominator: number, mode: RoundingMode): number" ], "reference": "import { roundDiv } from \"#fune/math.round-div@^1\";", "url": "http://www.functionalweave.com/functions/math.round-div" }, { "id": "math.basis-points", "tier": "optional", "why": "Converts \"12.5%\" to and from basis points exactly, for rates typed in by users.", "section": "rates", "from": "money-basics", "version": "2.0.0", "summary": "Convert a rate between percent, basis points and a plain ratio exactly, as decimal text or integer basis points.", "status": "stable", "license": "NOASSERTION", "languages": [ "typescript", "python", "rust" ], "available": true, "group": true, "functions": [ "convertRate", "toBasisPoints", "fromBasisPoints" ], "signatures": [ "export function convertRate(value: string, fromUnit: RateUnit, toUnit: RateUnit): string", "export function toBasisPoints(value: string, unit: RateUnit): number", "export function fromBasisPoints(basisPoints: number, unit: RateUnit): string" ], "reference": "import { convertRate, toBasisPoints, fromBasisPoints } from \"#fune/math.basis-points@^2\";", "url": "http://www.functionalweave.com/functions/math.basis-points" }, { "id": "math.percent-change", "tier": "optional", "why": "Percentage change between two figures in basis points, for \"up 4.2% on last month\".", "section": "rates", "from": "money-basics", "version": "1.0.0", "summary": "Percentage change from one value to another, in basis points, with an explicit rounding mode.", "status": "stable", "license": "NOASSERTION", "languages": [ "typescript", "python", "rust" ], "available": true, "group": false, "functions": [ "percentChange" ], "signatures": [ "export function percentChange(fromValue: number, toValue: number, mode: RoundingMode): number | null" ], "reference": "import { percentChange } from \"#fune/math.percent-change@^1\";", "url": "http://www.functionalweave.com/functions/math.percent-change" }, { "id": "math.rational", "tier": "optional", "why": "Exact fractions for rates that must not drift across many steps.", "section": "rates", "from": "money-basics", "version": "2.0.0", "summary": "Exact fraction arithmetic, always reduced, for rates and ratios that must not drift.", "status": "stable", "license": "NOASSERTION", "languages": [ "typescript", "python", "rust" ], "available": true, "group": true, "functions": [ "calculateRational", "rational", "addRational", "subtractRational", "multiplyRational", "divideRational", "compareRational", "rationalToInteger" ], "signatures": [ "export function calculateRational(a: Rational, op: RationalOp, b: Rational): Rational", "export function rational(numerator: number, denominator: number): Rational", "export function addRational(a: Rational, b: Rational): Rational", "export function subtractRational(a: Rational, b: Rational): Rational", "export function multiplyRational(a: Rational, b: Rational): Rational", "export function divideRational(a: Rational, b: Rational): Rational", "export function compareRational(a: Rational, b: Rational): number", "export function rationalToInteger(r: Rational, mode: RoundingMode): number" ], "reference": "import { calculateRational, rational, addRational, subtractRational, multiplyRational, divideRational, compareRational, rationalToInteger } from \"#fune/math.rational@^2\";", "url": "http://www.functionalweave.com/functions/math.rational" }, { "id": "math.round-div-big", "tier": "optional", "why": "Rounded division on numbers past 2^53, for very large totals.", "section": "rates", "from": "money-basics", "version": "1.0.0", "summary": "Divide two integers of any size with an explicit rounding mode, on decimal strings, for exact money sums past 2^53.", "status": "stable", "license": "NOASSERTION", "languages": [ "typescript", "python", "rust" ], "available": true, "group": false, "functions": [ "roundDivBig" ], "signatures": [ "export function roundDivBig(numerator: string, denominator: string, mode: RoundingMode): string" ], "reference": "import { roundDivBig } from \"#fune/math.round-div-big@^1\";", "url": "http://www.functionalweave.com/functions/math.round-div-big" } ], "gaps": [] }, { "key": "splitting", "title": "Splitting", "purpose": "Divide an amount between people, periods or lines so the parts add back to the whole.", "from": "money-basics", "members": [ { "id": "money.allocate", "tier": "core", "why": "Splits an amount by ratios (60/40, by quantity) without losing or inventing a penny.", "section": "splitting", "from": "money-basics", "version": "1.0.1", "summary": "Split an amount across ratios without losing or inventing a single minor unit.", "status": "stable", "license": "NOASSERTION", "languages": [ "typescript", "python", "rust" ], "available": true, "group": false, "functions": [ "allocate" ], "signatures": [ "export function allocate(amount: Money, ratios: readonly number[]): readonly Money[]" ], "reference": "import { allocate } from \"#fune/money.allocate@^1\";", "url": "http://www.functionalweave.com/functions/money.allocate" }, { "id": "money.split-even", "tier": "optional", "why": "Splits an amount into n near-equal parts that sum exactly, for instalments or shares.", "section": "splitting", "from": "money-basics", "version": "1.0.0", "summary": "Split an amount into n near-equal parts that add back up to exactly the whole.", "status": "stable", "license": "NOASSERTION", "languages": [ "typescript", "python", "rust" ], "available": true, "group": false, "functions": [ "splitEven" ], "signatures": [ "export function splitEven(amount: Money, parts: number): readonly Money[]" ], "reference": "import { splitEven } from \"#fune/money.split-even@^1\";", "url": "http://www.functionalweave.com/functions/money.split-even" } ], "gaps": [] }, { "key": "display", "title": "Display and input", "purpose": "Show amounts to people and read what they type.", "from": "money-basics", "members": [ { "id": "money.format", "tier": "core", "why": "Renders an amount as text with the currency's real number of decimal places.", "section": "display", "from": "money-basics", "version": "1.0.0", "summary": "Render a monetary amount as text, using the currency's real minor-unit precision.", "status": "stable", "license": "NOASSERTION", "languages": [ "typescript", "python", "rust" ], "available": true, "group": false, "functions": [ "formatMoney" ], "signatures": [ "export function formatMoney(amount: Money): string" ], "reference": "import { formatMoney } from \"#fune/money.format@^1\";", "url": "http://www.functionalweave.com/functions/money.format" }, { "id": "money.parse", "tier": "optional", "why": "Reads \"£1,234.50\" or \"1.234,50 €\" typed by a user into minor units, strictly.", "section": "display", "from": "money-basics", "version": "1.0.0", "summary": "Parse \"£1,234.50\" or \"1.234,50 €\" into integer minor units, strictly: no guessing, no rounding.", "status": "stable", "license": "NOASSERTION", "languages": [ "typescript", "python", "rust" ], "available": true, "group": false, "functions": [ "parseMoney" ], "signatures": [ "export function parseMoney(text: string, currency: string, style: NumberStyle): Money" ], "reference": "import { parseMoney } from \"#fune/money.parse@^1\";", "url": "http://www.functionalweave.com/functions/money.parse" }, { "id": "money.currency-digits", "tier": "optional", "why": "How many decimal places each ISO 4217 currency has, for input boxes and validation.", "section": "display", "from": "money-basics", "version": "1.0.0", "summary": "How many decimal places a currency's minor unit has, from the ISO 4217 list.", "status": "stable", "license": "NOASSERTION", "languages": [ "typescript", "python", "rust" ], "available": true, "group": false, "functions": [ "currencyDigits" ], "signatures": [ "export function currencyDigits(currency: string): number" ], "reference": "import { currencyDigits } from \"#fune/money.currency-digits@^1\";", "url": "http://www.functionalweave.com/functions/money.currency-digits" } ], "gaps": [] }, { "key": "currencies", "title": "Other currencies", "purpose": "Convert between currencies at a rate you hold.", "from": "money-basics", "members": [ { "id": "money.convert", "tier": "optional", "why": "Converts an amount at a supplied exact rate with explicit rounding.", "section": "currencies", "from": "money-basics", "version": "1.0.0", "summary": "Convert an amount to another currency at a supplied exact rate, with an explicit rounding mode.", "status": "stable", "license": "NOASSERTION", "languages": [ "typescript", "python", "rust" ], "available": true, "group": false, "functions": [ "convertMoney" ], "signatures": [ "export function convertMoney(amount: Money, rate: ExchangeRate, mode: RoundingMode): Money" ], "reference": "import { convertMoney } from \"#fune/money.convert@^1\";", "url": "http://www.functionalweave.com/functions/money.convert" } ], "gaps": [] }, { "key": "date-arithmetic", "title": "Calendar arithmetic", "purpose": "Move and measure ISO dates exactly, with no date library and no clock reads.", "from": "dates-basics", "members": [ { "id": "dates.add-days", "tier": "core", "why": "Shifts a date by whole days, for due dates and windows.", "section": "date-arithmetic", "from": "dates-basics", "version": "1.0.0", "summary": "Shift an ISO date by a whole number of days, forwards or backwards, with exact calendar arithmetic.", "status": "stable", "license": "NOASSERTION", "languages": [ "typescript", "python", "rust" ], "available": true, "group": false, "functions": [ "addDays" ], "signatures": [ "export function addDays(iso: string, days: number): string" ], "reference": "import { addDays } from \"#fune/dates.add-days@^1\";", "url": "http://www.functionalweave.com/functions/dates.add-days" }, { "id": "dates.add-months", "tier": "core", "why": "Adds months clamping to month end, so 31 January plus a month is the end of February.", "section": "date-arithmetic", "from": "dates-basics", "version": "1.0.0", "summary": "Add calendar months to an ISO date, clamping to the month end: 31 Jan + 1 month is 28 or 29 Feb.", "status": "stable", "license": "NOASSERTION", "languages": [ "typescript", "python", "rust" ], "available": true, "group": false, "functions": [ "addMonths" ], "signatures": [ "export function addMonths(iso: string, months: number): string" ], "reference": "import { addMonths } from \"#fune/dates.add-months@^1\";", "url": "http://www.functionalweave.com/functions/dates.add-months" }, { "id": "dates.days-between", "tier": "core", "why": "Signed calendar days between two dates, for ages of invoices and stays.", "section": "date-arithmetic", "from": "dates-basics", "version": "1.0.0", "summary": "Calendar days from one ISO date to another, signed: negative when the second date is earlier.", "status": "stable", "license": "NOASSERTION", "languages": [ "typescript", "python", "rust" ], "available": true, "group": false, "functions": [ "daysBetween" ], "signatures": [ "export function daysBetween(startIso: string, endIso: string): number" ], "reference": "import { daysBetween } from \"#fune/dates.days-between@^1\";", "url": "http://www.functionalweave.com/functions/dates.days-between" }, { "id": "dates.month-boundaries", "tier": "core", "why": "First and last day of a date's month, for monthly periods and statements.", "section": "date-arithmetic", "from": "dates-basics", "version": "1.0.0", "summary": "The first day, last day and length of the calendar month containing a date.", "status": "stable", "license": "NOASSERTION", "languages": [ "typescript", "python", "rust" ], "available": true, "group": false, "functions": [ "monthBoundaries" ], "signatures": [ "export function monthBoundaries(iso: string): MonthBoundaries" ], "reference": "import { monthBoundaries } from \"#fune/dates.month-boundaries@^1\";", "url": "http://www.functionalweave.com/functions/dates.month-boundaries" }, { "id": "dates.day-of-week", "tier": "core", "why": "ISO weekday of a date, for weekend rules and opening hours.", "section": "date-arithmetic", "from": "dates-basics", "version": "1.0.0", "summary": "The ISO 8601 day of the week for a date: 1 is Monday through 7 is Sunday.", "status": "stable", "license": "NOASSERTION", "languages": [ "typescript", "python", "rust" ], "available": true, "group": false, "functions": [ "dayOfWeek" ], "signatures": [ "export function dayOfWeek(iso: string): number" ], "reference": "import { dayOfWeek } from \"#fune/dates.day-of-week@^1\";", "url": "http://www.functionalweave.com/functions/dates.day-of-week" }, { "id": "dates.is-leap-year", "tier": "optional", "why": "Whether a year is a leap year, for 365/366-day calculations.", "section": "date-arithmetic", "from": "dates-basics", "version": "1.0.0", "summary": "Whether a year is a Gregorian leap year: every 4th, except centuries, except every 400th.", "status": "stable", "license": "NOASSERTION", "languages": [ "typescript", "python", "rust" ], "available": true, "group": false, "functions": [ "isLeapYear" ], "signatures": [ "export function isLeapYear(year: number): boolean" ], "reference": "import { isLeapYear } from \"#fune/dates.is-leap-year@^1\";", "url": "http://www.functionalweave.com/functions/dates.is-leap-year" }, { "id": "dates.overlap", "tier": "optional", "why": "Days two date ranges share, for prorating and clash checks.", "section": "date-arithmetic", "from": "dates-basics", "version": "1.0.0", "summary": "Days two date ranges have in common, with the end of each range stated as inclusive or exclusive.", "status": "stable", "license": "NOASSERTION", "languages": [ "typescript", "python", "rust" ], "available": true, "group": false, "functions": [ "overlapDays" ], "signatures": [ "export function overlapDays(aStart: string, aEnd: string, bStart: string, bEnd: string, endInclusive: boolean): number" ], "reference": "import { overlapDays } from \"#fune/dates.overlap@^1\";", "url": "http://www.functionalweave.com/functions/dates.overlap" } ], "gaps": [] }, { "key": "reporting-periods", "title": "Periods and reporting dates", "purpose": "Put dates into the periods reports are grouped by.", "from": "dates-basics", "members": [ { "id": "dates.quarter", "tier": "core", "why": "Calendar and fiscal quarter of a date for any year-start month.", "section": "reporting-periods", "from": "dates-basics", "version": "1.0.0", "summary": "Calendar quarter and fiscal quarter of a date, with the fiscal year and quarter date ranges, for any start month.", "status": "stable", "license": "NOASSERTION", "languages": [ "typescript", "python", "rust" ], "available": true, "group": false, "functions": [ "quarter" ], "signatures": [ "export function quarter(iso: string, fiscalYearStartMonth: number): Quarter" ], "reference": "import { quarter } from \"#fune/dates.quarter@^1\";", "url": "http://www.functionalweave.com/functions/dates.quarter" }, { "id": "dates.week-number", "tier": "optional", "why": "ISO week number and week-year, for weekly reports.", "section": "reporting-periods", "from": "dates-basics", "version": "1.0.0", "summary": "ISO 8601 week number and week-numbering year of a date: weeks start Monday, week 1 holds the first Thursday.", "status": "stable", "license": "NOASSERTION", "languages": [ "typescript", "python", "rust" ], "available": true, "group": false, "functions": [ "weekNumber" ], "signatures": [ "export function weekNumber(iso: string): IsoWeek" ], "reference": "import { weekNumber } from \"#fune/dates.week-number@^1\";", "url": "http://www.functionalweave.com/functions/dates.week-number" }, { "id": "dates.day-count-fraction", "tier": "optional", "why": "Year fraction by ACT/365F, ACT/360, 30/360 or ACT/ACT, for interest periods.", "section": "reporting-periods", "from": "dates-basics", "version": "1.0.0", "summary": "Year fraction between two dates by ACT/365F, ACT/360, 30/360, 30E/360 or ACT/ACT ISDA, as an exact fraction.", "status": "stable", "license": "NOASSERTION", "languages": [ "typescript", "python", "rust" ], "available": true, "group": false, "functions": [ "dayCountFraction" ], "signatures": [ "export function dayCountFraction(startIso: string, endIso: string, convention: DayCountConvention): YearFraction" ], "reference": "import { dayCountFraction } from \"#fune/dates.day-count-fraction@^1\";", "url": "http://www.functionalweave.com/functions/dates.day-count-fraction" } ], "gaps": [] }, { "key": "working-days", "title": "Working days and holidays", "purpose": "Skip weekends and public holidays when counting or adding days.", "from": "dates-basics", "members": [ { "id": "dates.bank-holidays", "tier": "core", "why": "UK bank holidays for a region and year, as gov.uk publishes them.", "section": "working-days", "from": "dates-basics", "version": "1.0.1", "summary": "UK bank and public holidays for a region and year, as published by gov.uk, including one-off holidays.", "status": "stable", "license": "NOASSERTION", "languages": [ "typescript", "python", "rust" ], "available": true, "group": false, "functions": [ "bankHolidays" ], "signatures": [ "export function bankHolidays(region: UkRegion, year: number): readonly BankHoliday[]" ], "reference": "import { bankHolidays } from \"#fune/dates.bank-holidays@^1\";", "url": "http://www.functionalweave.com/functions/dates.bank-holidays" }, { "id": "dates.add-business-days", "tier": "core", "why": "Moves a date by working days, skipping weekends and a holiday list.", "section": "working-days", "from": "dates-basics", "version": "1.0.0", "summary": "Move a date forward or back by working days, skipping weekends and a caller-supplied holiday list.", "status": "stable", "license": "NOASSERTION", "languages": [ "typescript", "python", "rust" ], "available": true, "group": false, "functions": [ "addBusinessDays" ], "signatures": [ "export function addBusinessDays(iso: string, days: number, holidays: readonly string[]): string" ], "reference": "import { addBusinessDays } from \"#fune/dates.add-business-days@^1\";", "url": "http://www.functionalweave.com/functions/dates.add-business-days" }, { "id": "dates.business-days-between", "tier": "core", "why": "Working days between two dates, for SLAs and notice periods.", "section": "working-days", "from": "dates-basics", "version": "1.0.0", "summary": "Working days between two dates, excluding weekends and a caller-supplied holiday list.", "status": "stable", "license": "NOASSERTION", "languages": [ "typescript", "python", "rust" ], "available": true, "group": false, "functions": [ "businessDaysBetween" ], "signatures": [ "export function businessDaysBetween(startIso: string, endIso: string, holidays: readonly string[]): number" ], "reference": "import { businessDaysBetween } from \"#fune/dates.business-days-between@^1\";", "url": "http://www.functionalweave.com/functions/dates.business-days-between" } ], "gaps": [] }, { "key": "repeating-dates", "title": "Repeating schedules", "purpose": "Generate the dates of something that repeats.", "from": "dates-basics", "members": [ { "id": "dates.recurrence", "tier": "optional", "why": "The next n dates of a rule: monthly on the 31st, last Friday, every two weeks.", "section": "repeating-dates", "from": "dates-basics", "version": "1.0.0", "summary": "The next n dates of a repeating rule: monthly on a day, last weekday of the month, every k days or weeks, yearly.", "status": "stable", "license": "NOASSERTION", "languages": [ "typescript", "python", "rust" ], "available": true, "group": false, "functions": [ "recurrence" ], "signatures": [ "export function recurrence(rule: RecurrenceRule, startIso: string, count: number): readonly string[]" ], "reference": "import { recurrence } from \"#fune/dates.recurrence@^1\";", "url": "http://www.functionalweave.com/functions/dates.recurrence" } ], "gaps": [] }, { "key": "times", "title": "Times and durations", "purpose": "Work with times of day, durations and timestamps.", "from": "dates-basics", "members": [ { "id": "time.duration", "tier": "optional", "why": "Parses and adds durations like 1h30m in whole minutes, and formats the total.", "section": "times", "from": "dates-basics", "version": "1.0.0", "summary": "Parse durations written as 1h30m, 90m or 01:30, add them up in whole minutes, and format the total.", "status": "stable", "license": "NOASSERTION", "languages": [ "typescript", "python", "rust" ], "available": true, "group": false, "functions": [ "duration" ], "signatures": [ "export function duration(parts: readonly string[]): Duration" ], "reference": "import { duration } from \"#fune/time.duration@^1\";", "url": "http://www.functionalweave.com/functions/time.duration" }, { "id": "time.minutes-between", "tier": "optional", "why": "Minutes between two local date-times, across midnight.", "section": "times", "from": "dates-basics", "version": "1.0.0", "summary": "Minutes from one local date and time to another, correct across midnight; wall-clock time, no time zones.", "status": "stable", "license": "NOASSERTION", "languages": [ "typescript", "python", "rust" ], "available": true, "group": false, "functions": [ "minutesBetween" ], "signatures": [ "export function minutesBetween(startDate: string, startTime: string, endDate: string, endTime: string): number" ], "reference": "import { minutesBetween } from \"#fune/time.minutes-between@^1\";", "url": "http://www.functionalweave.com/functions/time.minutes-between" }, { "id": "time.round-to-increment", "tier": "optional", "why": "Rounds minutes to a billing increment such as 6 or 15.", "section": "times", "from": "dates-basics", "version": "1.0.0", "summary": "Round a duration in minutes to a billing increment such as 6 or 15 minutes, up, down or to nearest.", "status": "stable", "license": "NOASSERTION", "languages": [ "typescript", "python", "rust" ], "available": true, "group": false, "functions": [ "roundToIncrement" ], "signatures": [ "export function roundToIncrement(minutes: number, increment: number, mode: RoundingMode): number" ], "reference": "import { roundToIncrement } from \"#fune/time.round-to-increment@^1\";", "url": "http://www.functionalweave.com/functions/time.round-to-increment" }, { "id": "time.iso-to-unix", "tier": "optional", "why": "RFC 3339 timestamps to Unix seconds.", "section": "times", "from": "dates-basics", "version": "1.0.0", "summary": "An RFC 3339 timestamp with a Z or offset, such as 2026-09-26T13:00:00+01:00, to Unix time in whole seconds.", "status": "stable", "license": "NOASSERTION", "languages": [ "typescript", "python", "rust" ], "available": true, "group": false, "functions": [ "isoToUnix" ], "signatures": [ "export function isoToUnix(timestamp: string): number" ], "reference": "import { isoToUnix } from \"#fune/time.iso-to-unix@^1\";", "url": "http://www.functionalweave.com/functions/time.iso-to-unix" }, { "id": "time.unix-to-iso", "tier": "optional", "why": "Unix seconds to an ISO 8601 UTC timestamp.", "section": "times", "from": "dates-basics", "version": "1.0.0", "summary": "Unix time in seconds to an ISO 8601 UTC timestamp such as 2026-09-26T12:00:00Z, for years 0001 to 9999.", "status": "stable", "license": "NOASSERTION", "languages": [ "typescript", "python", "rust" ], "available": true, "group": false, "functions": [ "unixToIso" ], "signatures": [ "export function unixToIso(seconds: number): string" ], "reference": "import { unixToIso } from \"#fune/time.unix-to-iso@^1\";", "url": "http://www.functionalweave.com/functions/time.unix-to-iso" }, { "id": "time.countdown", "tier": "optional", "why": "Seconds left until a moment and a 4:05 style timer text.", "section": "times", "from": "dates-basics", "version": "1.0.0", "summary": "Seconds left until a Unix time, whether it has passed, and a timer text like 4:05, for tokens or retry waits.", "status": "stable", "license": "NOASSERTION", "languages": [ "typescript", "python", "rust" ], "available": true, "group": false, "functions": [ "countdown" ], "signatures": [ "export function countdown(until: number, now: number): Countdown" ], "reference": "import { countdown } from \"#fune/time.countdown@^1\";", "url": "http://www.functionalweave.com/functions/time.countdown" } ], "gaps": [] }, { "key": "contact", "title": "Contact details", "purpose": "Check and normalise a person's contact details before storing them.", "from": "validation-basics", "members": [ { "id": "validation.email", "tier": "core", "why": "Is an email address plausible, by a documented subset of RFC 5322.", "section": "contact", "from": "validation-basics", "version": "1.0.0", "summary": "Is this a plausible email address? A documented, pragmatic subset of RFC 5322, not the full grammar.", "status": "stable", "license": "NOASSERTION", "languages": [ "typescript", "python", "rust" ], "available": true, "group": false, "functions": [ "isEmail" ], "signatures": [ "export function isEmail(value: string): boolean" ], "reference": "import { isEmail } from \"#fune/validation.email@^1\";", "url": "http://www.functionalweave.com/functions/validation.email" }, { "id": "validation.phone-e164", "tier": "core", "why": "Normalises a phone number to +44… E.164 for a default country.", "section": "contact", "from": "validation-basics", "version": "2.0.0", "summary": "Normalise a phone number to E.164 (+447700900123) using a default country's trunk and dialling prefixes.", "status": "stable", "license": "NOASSERTION", "languages": [ "typescript", "python", "rust" ], "available": true, "group": false, "functions": [ "validatePhoneE164" ], "signatures": [ "export function validatePhoneE164(value: string, defaultCountry: string): PhoneE164" ], "reference": "import { validatePhoneE164 } from \"#fune/validation.phone-e164@^2\";", "url": "http://www.functionalweave.com/functions/validation.phone-e164" }, { "id": "validation.uk-postcode", "tier": "core", "why": "Validates a UK postcode and puts it in canonical form.", "section": "contact", "from": "validation-basics", "version": "2.0.0", "summary": "Validate a UK postcode and normalise it to canonical upper case with one space before the inward code.", "status": "stable", "license": "NOASSERTION", "languages": [ "typescript", "python", "rust" ], "available": true, "group": false, "functions": [ "validateUkPostcode" ], "signatures": [ "export function validateUkPostcode(value: string): UkPostcode" ], "reference": "import { validateUkPostcode } from \"#fune/validation.uk-postcode@^2\";", "url": "http://www.functionalweave.com/functions/validation.uk-postcode" }, { "id": "text.normalise-name", "tier": "optional", "why": "Tidies a typed name: spacing and title case with Mc, O' and hyphen rules.", "section": "contact", "from": "validation-basics", "version": "1.0.0", "summary": "Tidy a personal name: trim, collapse whitespace and title-case, with Mc, Mac, O', hyphen and van/de rules.", "status": "stable", "license": "NOASSERTION", "languages": [ "typescript", "python", "rust" ], "available": true, "group": false, "functions": [ "normaliseName" ], "signatures": [ "export function normaliseName(value: string): string" ], "reference": "import { normaliseName } from \"#fune/text.normalise-name@^1\";", "url": "http://www.functionalweave.com/functions/text.normalise-name" }, { "id": "auth.normalise-email", "tier": "optional", "why": "Lower-cases an email's domain for storage and lookup.", "section": "contact", "from": "validation-basics", "version": "1.0.0", "summary": "Trim an email address and lower-case its domain for storage and lookup, or null if it is not a plausible address.", "status": "stable", "license": "NOASSERTION", "languages": [ "typescript", "python", "rust" ], "available": true, "group": false, "functions": [ "normaliseEmail" ], "signatures": [ "export function normaliseEmail(value: string): string | null" ], "reference": "import { normaliseEmail } from \"#fune/auth.normalise-email@^1\";", "url": "http://www.functionalweave.com/functions/auth.normalise-email" } ], "gaps": [] }, { "key": "bank", "title": "Bank details", "purpose": "Check payee and customer bank details before money moves.", "from": "validation-basics", "members": [ { "id": "validation.iban", "tier": "core", "why": "Checks an IBAN's mod-97 checksum and its country's length.", "section": "bank", "from": "validation-basics", "version": "1.0.0", "summary": "Check an IBAN against the ISO 13616 mod-97-10 checksum and the registered length for its country.", "status": "stable", "license": "NOASSERTION", "languages": [ "typescript", "python", "rust" ], "available": true, "group": false, "functions": [ "isIban" ], "signatures": [ "export function isIban(value: string): boolean" ], "reference": "import { isIban } from \"#fune/validation.iban@^1\";", "url": "http://www.functionalweave.com/functions/validation.iban" }, { "id": "validation.bic", "tier": "optional", "why": "Checks a SWIFT/BIC code's format and splits it.", "section": "bank", "from": "validation-basics", "version": "1.0.0", "summary": "Check the format of a SWIFT/BIC code (8 or 11 characters) and split it into its parts.", "status": "stable", "license": "NOASSERTION", "languages": [ "typescript", "python", "rust" ], "available": true, "group": false, "functions": [ "validateBic" ], "signatures": [ "export function validateBic(value: string): BicCheck" ], "reference": "import { validateBic } from \"#fune/validation.bic@^1\";", "url": "http://www.functionalweave.com/functions/validation.bic" }, { "id": "validation.uk-sort-code-account", "tier": "optional", "why": "Checks a UK sort code and account number by the Vocalink modulus rules, against a table you supply.", "section": "bank", "from": "validation-basics", "version": "3.0.0", "summary": "Check a UK sort code and account number with the Vocalink/Pay.UK modulus rules, against a table you supply.", "status": "stable", "license": "NOASSERTION", "languages": [ "typescript", "python", "rust" ], "available": true, "group": false, "functions": [ "validateUkSortCodeAccount" ], "signatures": [ "export function validateUkSortCodeAccount(sortCode: string, accountNumber: string, table: UkModulusTable): UkSortCodeAccount" ], "reference": "import { validateUkSortCodeAccount } from \"#fune/validation.uk-sort-code-account@^3\";", "url": "http://www.functionalweave.com/functions/validation.uk-sort-code-account" }, { "id": "validation.uk-modulus-table", "tier": "optional", "why": "Parses Vocalink's VALACDOS and SCSUBTAB files into that table.", "section": "bank", "from": "validation-basics", "version": "1.0.0", "summary": "Parse Vocalink's VALACDOS.txt and SCSUBTAB.txt into the table UK sort code modulus checking needs.", "status": "stable", "license": "NOASSERTION", "languages": [ "typescript", "python", "rust" ], "available": true, "group": false, "functions": [ "parseUkModulusTable" ], "signatures": [ "export function parseUkModulusTable(valacdos: string, scsubtab: string): UkModulusTable" ], "reference": "import { parseUkModulusTable } from \"#fune/validation.uk-modulus-table@^1\";", "url": "http://www.functionalweave.com/functions/validation.uk-modulus-table" } ], "gaps": [] }, { "key": "check-digits", "title": "Identifiers and check digits", "purpose": "Catch mistyped reference numbers by their check digits.", "from": "validation-basics", "members": [ { "id": "validation.luhn", "tier": "optional", "why": "Luhn mod-10 check, for card numbers and many reference numbers.", "section": "check-digits", "from": "validation-basics", "version": "1.0.0", "summary": "Check a digit string against the Luhn mod-10 checksum used by payment cards and many identifiers.", "status": "stable", "license": "NOASSERTION", "languages": [ "typescript", "python", "rust" ], "available": true, "group": false, "functions": [ "isLuhn" ], "signatures": [ "export function isLuhn(value: string): boolean" ], "reference": "import { isLuhn } from \"#fune/validation.luhn@^1\";", "url": "http://www.functionalweave.com/functions/validation.luhn" }, { "id": "validation.uk-company-number", "tier": "optional", "why": "Checks a Companies House number's format and prefix.", "section": "check-digits", "from": "validation-basics", "version": "2.0.1", "summary": "Check a Companies House company number's format and prefix (SC, NI, OC, LP...) and zero-pad it to eight characters.", "status": "stable", "license": "NOASSERTION", "languages": [ "typescript", "python", "rust" ], "available": true, "group": false, "functions": [ "validateUkCompanyNumber" ], "signatures": [ "export function validateUkCompanyNumber(value: string): UkCompanyNumber" ], "reference": "import { validateUkCompanyNumber } from \"#fune/validation.uk-company-number@^2\";", "url": "http://www.functionalweave.com/functions/validation.uk-company-number" }, { "id": "validation.lei", "tier": "optional", "why": "Checks a Legal Entity Identifier's check digits.", "section": "check-digits", "from": "validation-basics", "version": "1.0.0", "summary": "Check a 20-character Legal Entity Identifier against its ISO 17442 / ISO 7064 MOD 97-10 check digits.", "status": "stable", "license": "NOASSERTION", "languages": [ "typescript", "python", "rust" ], "available": true, "group": false, "functions": [ "validateLei" ], "signatures": [ "export function validateLei(value: string): LeiCheck" ], "reference": "import { validateLei } from \"#fune/validation.lei@^1\";", "url": "http://www.functionalweave.com/functions/validation.lei" }, { "id": "validation.gtin", "tier": "optional", "why": "Checks an EAN/UPC/GTIN barcode number.", "section": "check-digits", "from": "validation-basics", "version": "1.1.0", "summary": "Check an EAN-8, UPC-A, EAN-13 or GTIN-14 barcode number against the GS1 mod-10 check digit.", "status": "stable", "license": "NOASSERTION", "languages": [ "typescript", "python", "rust" ], "available": true, "group": false, "functions": [ "validateGtin" ], "signatures": [ "export function validateGtin(value: string): GtinCheck" ], "reference": "import { validateGtin } from \"#fune/validation.gtin@^1\";", "url": "http://www.functionalweave.com/functions/validation.gtin" } ], "gaps": [] }, { "key": "masking", "title": "Displaying sensitive values", "purpose": "Show stored identifiers without exposing them.", "from": "validation-basics", "members": [ { "id": "text.mask", "tier": "optional", "why": "Masks all but the last digits of a card, account or phone number.", "section": "masking", "from": "validation-basics", "version": "1.0.0", "summary": "Mask all but the last n characters of a card, account or phone number, optionally keeping separators.", "status": "stable", "license": "NOASSERTION", "languages": [ "typescript", "python", "rust" ], "available": true, "group": false, "functions": [ "mask" ], "signatures": [ "export function mask(value: string, visible: number, maskChar: string, keepSeparators: boolean): string" ], "reference": "import { mask } from \"#fune/text.mask@^1\";", "url": "http://www.functionalweave.com/functions/text.mask" } ], "gaps": [] } ], "gaps": [ { "key": "starter-leaver-forms", "text": "Starter checklists, P45 and P60 documents: caps gives the figures, not the forms.", "section": "employees", "from": "payroll" }, { "key": "rti-submission", "text": "Sending FPS and EPS returns to HMRC under Real Time Information: the XML, the gateway and the credentials are yours.", "section": "deductions", "from": "payroll" }, { "key": "pension-provider-files", "text": "Contribution files for pension providers (NEST, The People's Pension) and enrolment letters.", "section": "deductions", "from": "payroll" }, { "key": "leave-requests", "text": "Requesting and approving leave, team calendars and clashes.", "section": "leave", "from": "payroll" }, { "key": "bacs-files", "text": "Writing the Bacs Standard 18 payment file or a bank's bulk-payment CSV.", "section": "payments", "from": "payroll" }, { "key": "timesheets", "text": "Clocking in and out and timesheet approval: Functional Weave prices hours worked, it does not record them.", "section": null, "from": "payroll" }, { "key": "fx-rate-source", "text": "Where exchange rates come from: money.convert takes a rate you supply; fetching and storing daily rates (ECB, a provider's API) is yours.", "section": null, "from": "money-basics" }, { "key": "money-storage", "text": "Storing amounts: the database columns (integer minor units plus a currency code) and their migrations are yours.", "section": null, "from": "money-basics" }, { "key": "time-zones", "text": "Time zones and daylight saving: caps works in ISO dates, UTC and wall-clock times; converting with the IANA tz rules is yours.", "section": null, "from": "dates-basics" }, { "key": "locale-formatting", "text": "Showing dates in a user's language and format (\"3 octobre 2026\"): caps returns ISO dates, not localised text.", "section": null, "from": "dates-basics" }, { "key": "non-uk-holidays", "text": "Public holidays outside the UK: dates.bank-holidays is UK only; pass another country's list to the working-day functions yourself.", "section": null, "from": "dates-basics" }, { "key": "address-lookup", "text": "Turning a postcode into a list of addresses (Royal Mail PAF or a lookup API) is network work and not in caps.", "section": null, "from": "validation-basics" }, { "key": "email-deliverability", "text": "Whether a mailbox exists (MX lookups, a confirmation email): validation.email checks the syntax only.", "section": null, "from": "validation-basics" }, { "key": "vocalink-data", "text": "The Vocalink modulus tables themselves: download them from Pay.UK under its terms; caps parses them but does not ship them.", "section": null, "from": "validation-basics" } ], "counts": { "members": 76, "core": 34, "optional": 42, "unreviewed": 18, "deprecated": [], "unavailable": [], "missing": [], "gaps": 14 }, "warnings": [ "10 core capabilities are unreviewed - they pass their tests but await an expert's sign-off; tell the user before relying on them, and never use one silently for tax, payroll, legal, clinical or other regulated rules: payroll.tax-code-parse, payroll.tax-period, payroll.pro-rata-salary, payroll.gross-to-net, payroll.income-tax, payroll.national-insurance, payroll.pension-auto-enrolment, payroll.student-loan, payroll.statutory-sick-pay, payroll.holiday-entitlement", "8 optional capabilities are unreviewed too: payroll.overtime, payroll.minimum-wage-check, payroll.net-to-gross, fleet.company-car-bik, payroll.statutory-maternity-pay, payroll.holiday-pay-accrual, payroll.notice-period, payroll.redundancy-pay", "UK only: PAYE, National Insurance, student loans, statutory pay and pensions follow HMRC and UK employment rules for each tax year.", "Not payroll or legal advice. Run the figures past HMRC's calculators or a payroll professional before paying people from them." ], "url": "http://www.functionalweave.com/suites/payroll", "owner": null }