subkit· Subscriptions & invoices
subkit brings plans, trials, proration and invoices into your TypeScript app. Your customers pay by TWINT, card or QR-bill; subkit renews, sends reminders and matches payments with your bank. The data stays in your database.
Pro
CHF 19.00
/ month
Who it is for
subkit handles recurring payments – from the SaaS with teams and limits to the club whose members pay in e-banking.
SaaS
Plans with features and limits, trials and prorated upgrades. hasFeature() and getLimit() decide in your code what a team may do.
Memberships
Monthly or yearly subscriptions with TWINT or card, saved once and renewed automatically. Receipts and reminders in four languages.
Club fees
An invoice with QR-bill instead of a card: members pay in e-banking, the camt.054 of your bank marks the invoice as paid.
Self-service
With <BillingPortal /> your customers change their plan, save TWINT or a card and download their invoices. Every payment lands as a row in your database.
import { createSubscriptions } from '@agentkit.ch/subkit'; const billing = createSubscriptions({ database: drizzleAdapter(db), provider: zahlsProvider({ instance: 'acme', }), plans: [basic, pro], tax: { rateBps: 810 }, });
POST /api/billing/webhook
waiting_
Basic
activeCHF 9.00 / month
Pro
CHF 19.00 / month
Invoices
2026-0142
15.10.2026 · TWINT
2026-0141
15.09.2026 · QR
billing_subscriptions
billing_invoices
select * from billing_invoices join teams on …
Features
From code that runs in production at Membear: plans, payments, invoices and the cases that only show up in production.
Plans & trials
Monthly or yearly, with a trial and a free plan. Hidden plans stay with their subscribers but are no longer sold.
Proration to the Rappen
When a team moves to a bigger plan mid-month, subkit works out the difference and charges it right away.
TWINT, card or invoice
Save a payment method once and charge it every period – or let customers pay by invoice with QR-bill.
Reminders & retries
Payment terms, automatic retries and reminder emails. Dunning levels with fees come next.
Entitlements & limits
hasFeature() and getLimit() read the current plan – no table of your own for features.
Bank reconciliation
Import camt.053 and camt.054 from your bank, match QR references to open invoices, mark them paid.
Emails & invoices
Receipts, reminders and renewals as HTML and text, printable invoices with QR payment part – in four languages.
VAT on every invoice
VAT line and CHE number on every invoice, worked out in whole Rappen instead of floating point.
MCP for your team
Find customers, change plans, cancel, mark invoices paid – from Claude or ChatGPT, behind your own sign-in.
Idempotent webhooks and compare-and-set updates: if the same payment arrives twice, it is still booked only once.
When
A TWINT payment arrives
CHF 19.00 · 2026-0143
Then
Receipts, reminders and order confirmations as HTML and text, with your mailer.
Deine Quittung für Pro
Acme AG
Votre commande #1042 est confirmée
Boutique Léman
Promemoria: fattura 2026-0142
FC Lugano Nord
Swiss by default
Generic billing libraries think in Stripe, cents and one language. Swiss customers pay by QR-bill and TWINT, expect VAT on every invoice and read it in German, French or Italian. agentkit starts there.
Receipt
Account / Payable to
Reference
Payable by
Currency
Amount
Payment part
Currency
Amount
Account / Payable to
Reference
Additional information
Payable by
For developers
Plans, payment provider and VAT in one file, one route for API and webhook, one component for the billing page.
Install
Add subscriptions with QR-bill and TWINT using @agentkit.ch/subkit. Read https://agentkit.ch/llms.txt first.
import { createSubscriptions } from '@agentkit.ch/subkit';
import { drizzleAdapter } from '@agentkit.ch/subkit/drizzle';
import { zahlsProvider } from '@agentkit.ch/subkit/zahls';
import { db, env } from './db';
export const billing = createSubscriptions({
// your Postgres, your tables
database: drizzleAdapter(db),
provider: zahlsProvider({ instance: 'acme', apiKey: env.ZAHLS_KEY }),
plans: [
{ id: 'free', name: 'Free', features: [], limits: {}, prices: {} },
{
id: 'pro',
name: 'Pro',
features: ['export'],
limits: {},
prices: { month: { amount: 1900, currency: 'CHF' } },
},
],
defaultPlanId: 'free',
tax: { rateBps: 810 }, // Swiss VAT 8.1 %
});The other kit
shopkit
Commerce
For club shops, SMEs, merch and gift cards
Products with variants, cart and checkout with TWINT or on invoice. shopkit reserves stock, works out shipping and VAT per product and sends the order confirmation.
Cart
Questions
Still unsure? The demos show the kits with their real options.
For anything paid on a recurring basis: SaaS subscriptions, memberships, club fees, courses on subscription. For selling products there is shopkit.
By TWINT or card through zahls.ch – the payment method is saved once and charged every period – or by invoice with a Swiss QR-bill. collectionMethods sets which ones you offer.
subkit retries automatically and sends a reminder email. While an invoice is overdue, subkit sells the customer nothing new until it is paid.
In your database. subkit runs as a library in your app and writes to your Postgres tables through the Drizzle adapter. There is no agentkit backend and no extra data processor.
Nothing. subkit is open source under MIT, with no fee per transaction. You only pay your payment provider.
Copy the setup prompt into your coding agent – or try subkit in the browser first.
Add subscriptions with QR-bill and TWINT using @agentkit.ch/subkit. Read https://agentkit.ch/llms.txt first.
