Systems we build

Payments, wallets & ledgers

The money layer of your product, built to be auditable from day one — Stripe payments with per-country VAT, multi-currency wallets on an append-only ledger, usage-based and subscription billing, and webhook-driven flows that survive retries without ever double-charging anyone.

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How we think, not just what we type

Concepts & patterns we work in

The ideas behind the tools — the patterns we've applied in production, not buzzwords.

Append-only, reconcilable ledgersStore in one currency, display in the user'sIdempotent, webhook-driven billingPer-country VAT computationUsage metering & cost observabilityWallet pooling & spending capsAudit trails

The stack we reach for

What we actually use

The tools and languages we have real, shipped experience in — not a wish list.

Payments
StripeApple Pay / Google PaySaved methods & auto-refill
Ledger
Append-only ledgerMulti-currency display (135+)Reconciliation
Billing
Usage-based / pay-as-you-goPer-country VATBonuses & gifting
Core
Open Mercato

Proof, not promises

On our radar

This is some of our newest work — much of it under wraps. The fastest way to see it is the two-week Automation Sprint, or just book a free audit.

Related

Explore further

Custom ERP & business systems →Booking & reservation systems →

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