Custom Software for FinTech & Financial Services
Secure, flexible, and compliant architecture tailored for the unique challenges of the FinTech & Financial Services sector.
Vivek Mishra — Founder & Lead Architect, ERPStack
Quick Answer
In short: a FinTech ERP has to be consistent and provable. ERPStack builds custom financial services software on a cryptographically chained PostgreSQL ledger, with PCI DSS v4.0 tokenisation that cuts audit scope, SEC Rule 17a-4 retention for trade records, and SOC 2 Type II and ISO 27001 evidence generated from the schema.
Why Custom ERP for FinTech & Financial Services?
Financial services demand the absolute highest level of transactional consistency, fraud prevention, and audit-readiness. Standard enterprise applications often lack the scalability to parse thousands of ledger modifications in real time, or charge high premium seat licensing fees to extend database schemas. A custom Fintech ERP provides isolated database partitioning and cryptographically verified ledger tables where every transaction is validated and logged immutably. It automates compliance reporting for FCA, SOC 1, and PCI-DSS Level 1. By deploying serverless Next.js edge nodes with Neon PostgreSQL, financial institutions achieve sub-50ms query responses, secure real-time currency conversion integrations, and zero vendor lock-in.
Industry Pain Points
- High-frequency transaction latency
- Complex regulatory reporting (PCI-DSS, SEC Rule 17a-4)
- Vulnerability to data breaches and credential theft
- Data isolation in multi-tenant environments
Engineering Blueprint
Financial systems demand Zero-Trust architectures and ACID-compliant transaction ledgers. Our FinTech blueprint avoids generic ORM pitfalls by utilizing Double-Entry Ledger patterns natively in PostgreSQL, ensuring balances can never logically drift.
Immutable Transaction Ledger
Instead of updating a user's balance row (which is prone to race conditions), we use an append-only ledger architecture. Next.js API routes execute raw SQL transactions wrapping both the credit and debit entries atomically.
// Transactional Ledger Execution
await db.transaction(async (tx) => {
await tx.insert(ledger).values({ accountId: 'A', amount: -500 });
await tx.insert(ledger).values({ accountId: 'B', amount: 500 });
});Our Solutions
- High-throughput Edge Compute and Caching
- Automated Compliance and Audit Exporters
- Isolated Multi-Tenant Database schemas
- SEC Rule 17a-4 compliant WORM storage
Compliance & Security
From Payment Card Industry (PCI) requirements to SEC archiving, we build systems that pass rigorous compliance audits.
PCI-DSS v4.0 Network Isolation
We deploy your Next.js application within a strict Virtual Private Cloud (VPC) with private subnets. Databases have no public IP addresses and are only accessible via AWS Systems Manager (SSM) bastion hosts.WORM Storage for SEC Rule 17a-4
Financial communications and trade executions are automatically archived into AWS S3 buckets configured with Object Lock (Write Once Read Many), making them legally tamper-proof for the mandatory 7-year retention period.
Standards we engineer to
- PCI-DSS v4.0
- SOC 2 Type II
- ISO 27001
- SEC Rule 17a-4
Get the Blueprint
Download our comprehensive Systems Architecture Blueprint to see how we architect compliant solutions.
Download BlueprintMetrics & Integrations
Illustrative engineering targets for this sector — the SLAs and capacities we design and build toward, not a live service dashboard.
Transaction Throughput
Ledger Drift
Data Archival SLA
Integration: Plaid
Integration: Stripe Connect
Integration: AWS KMS
Implementation Process
Threat Modeling
Identifying attack vectors and designing Zero-Trust boundaries.
Ledger Architecture
Designing append-only PostgreSQL schemas for absolute financial integrity.
Payment Gateway Integration
Secure tokenization and integration with core banking APIs.
Penetration Testing
Third-party whitebox and blackbox security audits before launch.
Proven in FinTech & Financial Services
Real-Time Fraud Detection Platform
Real-time fraud detection and risk scoring platform
Read Case StudyFrequently Asked Questions
Evidence. Any system can compute a balance; a financial services system has to prove how it got there after the fact, to somebody hostile. That means an append-only PostgreSQL ledger rather than mutable rows, a hash chain so tampering is detectable, and an Immutable Audit Trail that survives a Drizzle ORM schema migration. ERPStack builds that in PostgreSQL from the first commit, with RBAC, SSO and Terraform underneath, because retrofitting immutability into a financial services system designed to UPDATE is close to a rewrite.
By keeping the primary account number out of your systems entirely. If the card data goes straight from the browser or terminal to the payment provider and your database only ever stores a token, most of the environment falls out of scope, and what remains is the segment that touches the token vault. For financial services teams that is the single largest cost lever in a PCI DSS assessment — larger than any control you can add later, and it is a REST API boundary rather than a product.
The 51 future-dated requirements became mandatory on 31 March 2025. They are mostly engineering work rather than paperwork: targeted risk analyses, stronger authentication, protection of payment-page scripts, and automated log review. In a financial services build ERPStack treats them as GitHub Actions backlog items with owners rather than an assessment-week scramble, because several of them — script integrity in particular — change how the Next.js front end is deployed.
Two clocks run. SEC Rule 17a-4(b) requires not less than three years, the first two in an easily accessible place, while FINRA Rule 4511(b) requires at least six years for books and records with no other specified period, and ties format and media back to 17a-4. A financial services PostgreSQL schema that applies one blanket purge rule will breach one of them, so ERPStack models retention per record class under Drizzle ORM, with AWS object storage under a lock.
Not since the 2022 amendments. Rule 17a-4(f)(2)(i) allows an electronic recordkeeping system either to preserve records exclusively in a non-rewriteable, non-erasable format or to maintain a complete time-stamped audit trail of every modification and deletion; the broker-dealer compliance date was 3 May 2023. Financial services teams can therefore run a hash-chained PostgreSQL journal under Drizzle ORM, with AWS object storage under a retention lock as the second copy and Sentry watching the write path.
A written programme and a notification clock. 16 CFR 314.4(j) requires a non-banking financial institution to notify the FTC within 30 days of discovering a security event involving the unencrypted information of at least 500 consumers. For financial services engineering that means the system has to know how many records were exposed, which is a PostgreSQL query — and only answerable if access to customer records is logged at row level, under RBAC, in the first place.
Buy the general ledger, build the sub-ledger. Statutory books are a solved problem and packages do them well; what packages do badly is the product-specific ledger — fee accrual, revenue share, provisional pricing, multi-currency settlement — because it changes with the business. Financial services builds that succeed keep SAP S/4HANA or Oracle NetSuite for statutory reporting and put the moving part in PostgreSQL, joined over a REST or GraphQL API with Idempotency in API Design.
We generate it; we do not certify it. ERPStack holds no SOC 2 attestation of its own — it is a development firm — so the useful thing it can do is make the evidence fall out of the running financial services system: access reviews from the RBAC tables in PostgreSQL, change history from GitHub Actions, encryption and key rotation from Terraform state, ISO 27001 mappings from the same source. Your auditor tests those artefacts against your own financial services control set.