//payments.rail
VISA
••••••••••••4242
CARDHOLDER09/29
Move money end to end.
Stripe Connect, marketplace payouts, ACH and card rails, and the operator console. Shipped end to end.
Fintech
Fintech that moves real money.
We build custom fintech SaaS for founders and CTOs who need a partner that has actually moved money through the rails before. Payments, lending, trading, business finance. Tampa-based agency. Clients in Boston, Phoenix, and Tampa.
4
Production fintech platforms shipped since 2020
3
US states with active fintech clients (FL, MA, AZ)
10-16w
Typical fintech MVP timeline, kickoff to live
2020
First fintech engagement, consecutive years since
MostMostfintechfintechfailuresfailuresarearenotnotengineeringengineeringfailuresfailures--theytheyarearepartner-railpartner-raildecisionsdecisionsmademadebeforebeforethetheengineeringengineeringstarted.started.WeWehavehaveshippedshippedfourfourfintechfintechplatformsplatformssincesince2020,2020,pickedpickedthethewrongwrongrailrailononone,one,andandbuiltbuiltthethewaywayweweworkworkaroundaroundmakingmakingsuresureyouyoudodonot.not.
What we build
What we build for fintech founders
Six fintech surfaces, all of which we have shipped at least once in the last five years. Each has a payment-network, regulatory, and operator-tooling shape worth knowing before you scope.
//lending.flow
Approved
Underwriting
Pending KYC
Originate, underwrite, repay.
Origination, underwriting, repayment, and KYC/KYB in one flow. We connected practices, patients, and lenders on a dental-financing platform.
//trading.feed
Built for both audiences.
Real-time market data, order routing, and regulator-grade audit logs. Retail and institutional from one codebase.
//ledger.reconcile
Replace the spreadsheet stack.
AP/AR, ledger reconciliation, expense workflows, and multi-entity reporting. We replaced an SMB spreadsheet stack.
//fx.settle
USDEURGBP
Multi-currency, reconciled.
Multi-currency ledgers, rate sourcing, and settlement timing. The hard part is operational truth, not code.
//compliance.audit
Audit log
Role-based access
Data retention
A first-class feature, not a bolt-on.
Audit logging, role-based access, retention policies, and exception queues. Built in, not bolted on before an audit.
Why DesignKey for fintech
What we believe about building fintech the right way
Shipped for real money flows
Four platforms in production. Not pilots.
Production platforms4 live
Payments
Lending
Trading
Business finance
The right rail for your economics
The fee math decides, not the trend.
Transfer cost
Dwolla (ACH)0.22%
Stripe Connect0.30%
-8 bps saved
Tampa rates, US-time-zone delivery
East Coast hours, no offshoring.
DesignKey · Tampa
NYC
SF
Boston
We say no to scope we cannot back up
We name what we will not do.
Money-transmitter license
Sponsor BaaS programs
Write compliance memos
Senior-only engineering
Every engineer has shipped regulated product.
A.K.Senior
R.M.Senior
J.T.Senior
0 junior pass-through
Instrumented from week one
Your dashboard is live before launch.
Txn success
99.2%
Dispute rate
0.4%
Case studies
Four fintech platforms we shipped
Each was a real engagement with real users moving real money. Three are named clients. One asked to stay unnamed. The work is documented either way.
Go deeper
Related services and deeper guides
Fintech work touches every layer of the stack. These pages dig into the parts that matter most for a fintech build.
FAQ
Fintech development questions, answered
The questions we get from founders and CTOs evaluating a fintech build. Pulled from real discovery calls in 2026.
Ready to get started?
Building fintech in 2026? Let's talk.
No sales pitch. A working session on your payment rails, regulatory surface, and operator tooling. We share what we have shipped and where we have failed. You decide if we fit.
NDA Protected
100% Satisfaction
Dedicated Team
Reply in 1 Business Day
More industries
Explore the other industries we build for
Fintech is one of five verticals we treat as a pillar. Each earns its place with shipped case studies and a written point of view.
