Payments practice
Stripe, Adyen, Unit, Checkout.com and Plaid, plus push-to-card over Visa Direct and Mastercard MoneySend. Every integration we work on, new or existing, gets idempotency, duplicate-event protection, partial-failure recovery and a reconciliation finance can close the month from.
01 / 03 Ledger
Every write that creates, moves or refunds money carries an idempotency key built from a business identifier. The request record is saved before the provider call, so a retry after a crash finds the attempt it is retrying.
02 / 03 Provider and bank
Webhooks arrive twice, out of order or not at all. A timeout after the provider accepted is unknown, not failed, and is resolved by query before any retry. Event IDs carry a unique constraint, so a duplicate is acknowledged and ignored.
03 / 03 Tie-out
Ledger, provider and bank, compared automatically at least once a day. Tolerance zero on count, one minor unit on amount. Every break lands in a queue with an owner and an age, and month-end closes from system data, not a spreadsheet.
What breaks
paid arrives before created.| Transaction | Ledger | Provider | Bank | State |
|---|---|---|---|---|
| po_8f3a21 payout | 1,240.00 | 1,240.00 | 1,240.00 | Matched |
| ch_51d0e4 charge | 89.90 | 89.90 | 89.90 | Matched |
| po_77b2c9 payout | 500.00 | 500.00 | none | Missing at bank |
| ch_9c14aa charge | 42.00 | 42.00 | 41.00 | Short 1.00 |
| po_31e5f0 payout | 300.00 | 600.00 | 600.00 | Duplicate at provider |
| rf_2a07d1 refund | -15.00 | -15.00 | -15.00 | Matched |
3 matched3 to explain before closeTolerance: 0 on count, 1 minor unit on amount
What the ledger holds, what the provider holds and what the bank holds, for one day. The assessment reviews this tie-out on your system.
What we build
Every build is priced from the assessment's findings, so the price is fixed before work starts.
01 / 03 Fixed price
Accepting, paying out and reconciling on your rails, with a date, a change-control clause and milestone billing. Every change is checked against our 42-item acceptance checklist.
See the assessment02 / 03 Monthly
On what we built: breaks, payout runs and the alerts behind them. Priced on response time and coverage.
Every fee on the pricing page03 / 03 Fixed package price
Test automation and a safety net for money-handling code: idempotency suites, ledger reconciliation under load, decimal precision, KYC state machines and compliance traceability. After a build, or before an audit or a launch.
Ask about it on a callMethod
01 / 04 1 or 2 weeks
We map every flow that creates, moves or refunds money, test how each one fails, and check reconciliation across ledger, provider and bank.
02 / 04 Report
A severity-ranked findings report, a target design, a costed roadmap and a fixed-price quote for the build.
03 / 04 Fixed price
A date, change control and milestone billing. A design document comes before any code that touches money, and you get a written status every week.
04 / 04 Yours
The system and its design documents move to your team. If you want us on call for it, the retainer covers what we built.
Assessment
Every payments engagement starts here: one or two weeks at a fixed fee. You keep the report even if someone else does the build.
Published fee
$9,500One week, single rail
$14,500Two weeks, multi-rail or payouts
Half on signature, half on delivery. We don't bill by the hour.
Case study
Push-to-card payouts on a regulated banking platform, built so every payout either lands on the card or goes back to the account it came from. Delivered by our principal, Rey Narvaez, in regulated production before Aripone was formed.
Self-check
Fifteen questions from the acceptance checklist, two minutes, scored in your browser. Nothing is sent. It tells you whether money can be duplicated or lost silently today, and what to fix first.
Example result
36/ 100At risk
Illustrative example, not a client's data.
Scoping call
Bring the failure that worries you most. In 30 minutes we'll tell you whether the assessment is worth it.