Why build a ledger instead of storing balances?

A stored balance tells you a number but not how it got there. A double-entry ledger records every movement as balanced entries that are never edited, so you can rebuild any balance at any date, explain it to an auditor and find the exact transaction behind a discrepancy. It also makes daily reconciliation possible.

Which KYC providers can you integrate?

Whichever vendor your compliance team and bank partner approve, such as Persona, Alloy, Onfido or Plaid Identity Verification. The integration covers document and selfie capture, status webhooks, retries, manual review screens and storing results in line with your retention policy, so switching vendors later touches one module rather than the whole onboarding flow.

Can you build ACH payments with Plaid?

Yes. Plaid handles account linking and verification, and the money movement itself runs through your processor or sponsor bank, such as Stripe, Dwolla or a bank API. We handle return codes, retries, holds while funds settle and customer notifications, and record every state change against the payment in your ledger.

Do you work with fintech startups before they have a bank partner?

Yes. We can build against sandboxes from Stripe, Plaid and other providers while you finalize partner agreements, keeping each integration behind an interface so a change of bank or processor touches one module. Regulated activities stay with your licensed partners, and we design the software around that division of responsibility.

Business planning session with a laptop and printed documents

Money movement, built carefully

Fintech software development for US startups and finance teams

We build the parts of fintech products where mistakes cost real money: payment flows, ledgers, reconciliation, KYC onboarding and audit trails, for US startups and finance teams working with licensed banking and payment partners.

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About custom solutions

Payments through Stripe, ACH and your banking partners

Card payments, payouts and marketplace flows usually start on Stripe, including Stripe Connect when money moves between your platform and its users. For bank payments we integrate ACH through Plaid for account linking and verification, connected to your processor or sponsor bank's API. Every money movement is idempotent, retried safely and tied to a record your support team can look up.

Card data stays out of your systems through tokenization: hosted fields or Stripe Elements collect the card, and your servers only ever see a token. That keeps your PCI DSS scope as small as possible, which shortens your self-assessment and reduces what your assessors need to review. We work inside your PCI program rather than claiming a certification of our own.

Ledgers and reconciliation that finance can trust

Balances should be derived from a ledger, not stored as a number someone updates. We build double-entry ledgers in PostgreSQL where every movement is an immutable journal entry with balanced debits and credits, amounts held as integers in minor units, and corrections made by reversing entries rather than edits. Any account balance at any past date can be reproduced exactly.

Reconciliation jobs compare your ledger with processor reports, bank statements and payout files every day, match transactions automatically and put the rest in an exceptions queue with the reason for each mismatch. Finance staff resolve exceptions in an internal tool with notes and approvals, so month-end becomes a review of a short list instead of a week of spreadsheet matching.

KYC onboarding and audit trails

Identity checks are handled by specialist KYC and KYB vendors such as Persona, Alloy or Plaid Identity Verification, which we integrate into your onboarding flow with clear states for pending, approved, rejected and manual review. Your compliance team sets the rules and makes the decisions. Every check, document request, approval and override is written to an append-only audit trail that answers examiner and partner bank questions.

Fintech software we build

Payment flows on Stripe and Stripe Connect for platforms and marketplaces
ACH account linking and verification through Plaid
Double-entry ledgers with immutable journal entries
Daily reconciliation against processor, bank and payout reports
KYC and KYB onboarding with vendor integrations and review queues
Tokenized card capture that keeps raw card data off your servers
Internal finance tools for approvals, refunds and exception handling

Built for the market

What US fintech teams and their partners expect

A clear line between what your licensed partners do and what your software does
Append-only audit trails your compliance team and sponsor bank can review
Masked or synthetic financial data in development and testing
Production financial data limited to named engineers, with every access logged
Work inside your PCI DSS and SOC 2 programs, with no certification claimed by us

Time zone: US Eastern time is nine to ten hours behind Lahore. A fixed overlap window in your morning is agreed at the start of the project, and the rest of the work happens overnight for you, so each day starts with progress to review.
Payments we integrate: Stripe, PayPal, Square, Authorize.Net, ACH bank transfers, Apple Pay
Tax and data: Built for US sales tax through providers such as Stripe Tax, Avalara or TaxJar. Personal data handled in line with the CCPA/CPRA and other US state privacy laws.
Language: English.

Questions

Fintech software development: common questions

No, and for most products your development vendor does not need to be. We design so card data never touches your servers, using tokenization through Stripe or your processor, which keeps your own PCI scope small. We follow your PCI program's controls and document what we built for your assessment.

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