APIs for Lending Systems, Built by People Who Run Their Own
A lending API isn't a CRUD endpoint with authentication on it. It carries money movement, consent, audit obligations and regulatory disclosures. We build that layer for banks and NBFCs — and we run the same kind of API in production behind our own products.
Lending APIs in India connect a loan origination flow to credit bureaus, KYC and identity services, payment rails, tax data and statement analysis, under regulatory requirements covering consent, disclosure, audit trails and data handling. Sastra Technologies builds and integrates these APIs for banks and NBFCs, and operates its own lending APIs in production.
What makes a lending API different?
The requirements that don't apply to ordinary integrations
Money movement has to be idempotent
A retried disbursement request that creates a second disbursement is not a bug you fix in the next sprint. Every mutating endpoint in a lending flow needs an idempotency contract, and most generic API work has never needed one.
Everything is evidence
Who called what, with which consent, at which timestamp, and what the upstream returned — all of it may be read back by an auditor or an inspection team years later. Audit logging is a design input, not an operational afterthought.
Consent is a data structure
Whose consent, for what purpose, valid until when, and revocable. It has to be stored, checked at call time, and demonstrable afterwards.
Failure has a regulatory shape
An upstream bureau timing out, a mandate registration failing, a KYC service returning ambiguously — each needs a defined outcome that keeps the borrower's position clear, because "the integration was down" is not a defence when a disclosure obligation had a clock on it.
Reconciliation is permanent
Any flow touching a payment rail needs a reconciliation path, because the ledger of record is somebody else's.
What we build
The integration surfaces a lending flow actually needs
- Credit bureaus — enquiry and reporting across the credit information companies. See our Credit Bureau Integration service.
- Identity and KYC — Aadhaar-based verification, PAN validation, CKYC, video KYC.
- Payment rails — mandate registration and collections, disbursement instruction and status, with reconciliation.
- Tax and business data — GST return data for revenue corroboration.
- Statement analysis — including our own AB Analyse API, which is the same class of integration we build for clients.
- Core system connectivity — core banking, loan origination and loan management systems, so the above reaches the system your team actually works in.
And the parts nobody scopes
Bank-facing service features, resilience and monitoring — the code that keeps a lending flow trustworthy.
01
Rate limiting and backoff
Against upstreams that throttle without warning.
02
Token lifecycle and rotation
Credentials that expire in production, not only in the sandbox.
03
Webhook delivery you can trust
With replay, so a missed event is recoverable.
04
Sandbox-to-production parity
Versioning that doesn't break a live underwriting flow, and structured error semantics your credit engine can branch on.
Security
Where we've done our thinking in public
API security in financial services is a subject we write about rather than just claim: authentication and authorisation design, token handling, PII exposure through over-permissive responses, and the failure modes that show up specifically in integration layers.
The regulatory layer
Requirements that land in the code, not the policy document
Digital lending conduct requirements
Where origination is digital, there are obligations around the Key Fact Statement, disclosure of lending service providers, cooling-off treatment and restrictions on automatic credit limit increases. Each is an implementation detail in the flow, not a footnote — a document to generate, a party to disclose, a window to enforce.
Data localisation
The digital lending framework carries requirements about lending data being held on servers located in India. This shapes architecture decisions early, and it is materially easier to satisfy in a design that stores as little as possible than in one that has to be retrofitted.
Consent and personal data
Purpose limitation, retention limits and borrower rights under India's data protection law apply to every integration that touches borrower information.
Audit and outsourcing expectations
Your regulator's view of your technology service providers extends to sub-processors and data location, which means integrations need documented answers about where data goes and who can reach it.
Proof
We ship this ourselves
AB Analyse runs on an API we built and operate: statements in, structured credit intelligence out, in under a minute, consumed by lenders through their own underwriting flows. It covers 110+ Indian banks.
AB Compliance — RBI returns and audit findings
Regulatory reporting has its own integration surface: pulling figures from core systems into returns, and keeping the audit trail intact end to end.
FAQ
Frequently asked questions
APIs for lending flows — credit bureau enquiry and reporting, KYC and identity verification, payment mandates and disbursement, tax data, statement analysis, and connections into core banking and loan origination systems. The common thread is that they carry money, consent or a regulatory obligation.
No. We do not. Our expertise is in financial services — banks, NBFCs and lending platforms. We build APIs that move money, hold consent, leave an audit trail, or meet a disclosure clock. We do not take general CRUD or consumer-app API work outside that domain.
Yes — if it is open-standards compliant: documented contracts, predictable auth, and error semantics another system can consume. If it is a closed proprietary surface we cannot integrate against cleanly, we will not wrap it. We will say so in the scoping conversation.
A few weeks to a few months, depending on the complexity of the exercise — how many upstreams you need, whether sandbox credentials exist, and how much reconciliation and audit logging the flow requires. Simple KYC wiring is short; a disbursement rail with reconciliation takes longer.
The client owns the code. We build it in your repositories, under your licence and access controls. There is no proprietary lock-in in the deliverable itself. Ongoing support can stay with us or move to your team — that is a commercial choice, not a technical one.
Yes. We provide ongoing support after go-live: incident response on the integrations we built, upstream-change handling, and versioning so a live underwriting flow is not broken by a silent vendor update. Scope and hours are agreed in the support arrangement.
PHP and Symfony. That is the stack we run in production behind our own lending APIs, including AB Analyse. If your estate is already on that stack, the work lands in a codebase your engineers can maintain. We do not rewrite a live platform onto something else for its own sake.