Software development for fintech and banking
Financial software is judged on things users never see: whether every rupee, dollar or pound can be traced, whether a repeated webhook can credit an account twice, and whether the product can answer an auditor’s question a year after launch.
RED SAG builds lending platforms, payment flows, wallets, onboarding and back-office tools for fintech startups, NBFCs, microfinance and co-operative lenders, and financial advisers in India, and for fintech founders in the UK, US, Australia and Canada who need an engineering team that treats money movement with care.
What makes fintech and banking software hard
Partners set the bar
Most fintechs launch through a bank, NBFC or payment aggregator. That partner’s due diligence, security questionnaire and technical requirements often decide the architecture before a single screen is designed.
Money must reconcile
Balances edited as a single number drift over time. Without a double-entry ledger and daily reconciliation against bank and gateway reports, small mismatches become month-end fire drills.
Regulation changes mid-build
RBI directions, NPCI circulars and FCA rules change often. Software needs configurable limits, disclosure templates and fees rather than values hard-coded in several places.
Onboarding drop-off
Every extra KYC step costs customers. Flows must be compliant and still fast on a mid-range Android phone with a patchy connection.
Legacy spreadsheets
Many NBFCs and co-operative lenders still run loan books and collections on Excel, making EMI tracking, overdue follow-up and regulatory reports slow and error-prone.
Software we build for fintech and banking
Lending and loan management
Loan origination, underwriting rules, Key Fact Statements, EMI schedules, repayments, collections and borrower portals for NBFCs, LSPs and co-operative lenders.
Loan Management SoftwarePayments and UPI
Gateway and UPI integration, payment links, subscriptions with UPI AutoPay and e-mandates, refunds, split settlements and reconciliation.
Payment Gateway IntegrationFintech MVPs and wallets
Customer apps and admin back offices for wallets, savings, investment and expense products, built on a ledger from the first version.
Fintech SoftwareKYC and onboarding
PAN, bank account and document verification, CKYC lookups, Video KYC integrations and maker-checker review queues through licensed providers.
KYC and eKYC IntegrationAccounting and finance back office
General ledger, GST-ready invoicing, reconciliations and management reports for finance teams and advisers.
Accounting SoftwareMobile banking-style apps
Cross-platform apps with biometric login, device binding, secure storage and push notifications for transactions.
Mobile AppsHow we approach these projects
Compliance discovery first
Before quoting, we ask who the regulated entity is, which directions and partner requirements apply, where data must be stored and how long records are kept. The answers become requirements, not afterthoughts.
Ledger before screens
We model accounts, entries and states of each transaction first. Screens and reports sit on top of a ledger that always balances.
Idempotency and reconciliation
Webhooks and callbacks are verified and processed exactly once, and a daily job compares your records with bank, gateway and partner files, flagging differences for a person to review.
Evidence by default
Consent records, disclosure versions, approvals and admin actions are logged with who, what and when, so due diligence and audits draw on data you already have.
Integrations we commonly build
Third-party access is sometimes limited by the provider. We confirm what is available for your account before quoting.
Payments (India)
- Razorpay
- Cashfree
- PayU
- UPI intent and QR via your PA
- UPI AutoPay
- e-NACH via sponsor bank or PA
Payments (abroad)
- Stripe
- PayPal
- Adyen
- GoCardless
- TrueLayer (UK open banking)
- Plaid (US)
Identity and data
- PAN and bank account verification APIs
- CKYC registry via partner
- DigiLocker
- Video KYC providers
- Account Aggregators
Credit and communication
- Credit bureaus (CIBIL, Experian, Equifax, CRIF High Mark) via licensed access
- SMS and WhatsApp Business API
- Email and push notifications
Compliance notes
Practical pointers, not legal advice. Rules change, so confirm the current position with your adviser; we build the software to match.
RBI digital lending and KYC
Loan flows need Key Fact Statements with APR, direct fund flows between borrower and lender, consent-based data collection and India-hosted borrower data. KYC methods depend on your partner’s authorisations.
Payment data and cards
Payment system data must be stored in India, and merchants may not store full card details; saved cards work through tokenisation provided by your gateway.
Data protection
The DPDP Act in India, and GDPR or UK GDPR abroad, shape consent, retention and deletion. Sector record-keeping rules can override deletion, so we design retention schedules per data type.
Security expectations
Partners often ask for role-based access, audit logs, encryption, penetration testing and vendor due diligence. We build for these and can arrange third-party testing on request.
More detail in our fintech compliance guide.
Relevant projects
Fintech Mobile App
A consumer finance app with biometric login, transfers and spending insights: the kind of customer-facing product most fintech briefs start with.
Tafsee Accounting Software
Cloud accounting with double-entry bookkeeping, tax reporting and financial dashboards, showing our back-office and ledger work.
SaaS Dashboard
Reporting and analytics dashboards similar to the portfolio, collections and risk views lenders use every day.
Frequently asked questions
Do you build for NBFCs and co-operative lenders, or only startups?
Both. Startups usually need a customer app and admin back office for a new product; established lenders more often need loan management, collections and reporting to replace spreadsheets or an ageing system. The engineering principles, ledger, audit trail and reconciliation, are the same.
Can you work within our partner bank’s requirements?
Yes. We ask for the partner’s technical and security requirements early, answer their questionnaires and join architecture reviews. It is far cheaper to build to their checklist than to rework after their review.
Will our data be hosted in India?
For Indian payment and lending products we host in an India cloud region in your own account, including backups and logs. For UK, EU or US products we host in the region your rules require.
Do you hold a licence or certification for financial software?
No. Licences belong to the regulated business, and we do not hold ISO 27001, SOC 2 or PCI DSS certification. We build software that supports your compliance and reduces your audit scope, and we are clear about which responsibilities stay with you.
How do you avoid double payments or wrong balances?
Every payment event is verified by signature and processed idempotently using a unique key, balances come from ledger entries rather than an editable number, and a daily reconciliation job compares your records with the bank and gateway so any mismatch is caught the next day, not at month end.
Other industries we work with
Retail and E-commerce
Stores, POS billing and inventory kept in sync, with GST invoicing, UPI and courier integrations.
Manufacturing and Textiles
Garment ERP, production and job work tracking, piece-rate payroll and buyer order management, built in Tiruppur.
Healthcare
Clinic management, booking, patient portals and telehealth, with privacy and busy front desks in mind.
Education
School management, fee collection, parent apps and course platforms, with children’s data handled carefully.
Hospitality and Travel
Direct booking engines, restaurant POS, table reservations and tour booking with payments and channel sync.
See also how we work and our security practices.
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