Variant Systems
All industries

Industry

Fintech

Secure, reliable financial technology.

Key challenges we address:

Regulatory compliance (PCI-DSS, SOC 2) Transaction accuracy — money can't go missing Security against fraud and attacks Real-time processing requirements Audit trails and reporting

Money Requires Care

When you’re building software that handles money, there’s no room for “it mostly works.” Transactions must be accurate. Systems must be secure. Auditors must be satisfied. One decimal point error can cost millions. One security breach can end your company.

We build fintech with these requirements as first principles. Not as features to add later. Not as compliance checkboxes. As the foundation everything else builds on.

The stakes in fintech are higher than almost any other domain. Users trust you with their money. Regulators watch your every move. Competitors look for any weakness. The margin for error is zero.

Industry-Specific Challenges

Fintech faces challenges that most industries don’t understand. The regulatory environment is complex and constantly evolving. Different states have different rules. Different products have different requirements. Money transmission, lending, investment advice, banking services — each has its own regulatory framework.

The technical requirements are demanding. Financial transactions must be atomic. They must be idempotent. They must handle failure gracefully. A payment that goes through twice is as bad as a payment that doesn’t go through at all. Sometimes worse.

Security threats are constant and sophisticated. Attackers target fintech specifically because that’s where the money is. Credential stuffing, account takeover, synthetic identity fraud, authorized push payment fraud — the attack vectors are endless and evolving.

Then there’s the integration challenge. Money doesn’t move in isolation. It moves through banks, processors, clearinghouses, and networks. Each has its own protocols, limitations, and failure modes. Making these systems work together reliably is harder than it looks.

Finally, there’s trust. Users need to trust your platform with their financial information. Banks need to trust you enough to partner with you. Regulators need to trust you enough to grant licenses. Building and maintaining this trust requires consistent execution over time.

What We Build

We’ve built fintech products across the financial services spectrum:

  • Payment platforms — Processing, reconciliation, reporting, dispute handling, and refund management for transaction volumes from thousands to millions per day
  • Financial dashboards — Real-time data for decision-making, from cash flow forecasting to portfolio analytics to treasury management
  • Lending systems — Applications, underwriting, decisioning, servicing, collections, and regulatory reporting for consumer, business, and specialty lending
  • Wealth management tools — Portfolio tracking, performance reporting, rebalancing, tax-loss harvesting, and client communication
  • Banking integrations — Plaid, Stripe, payment rails, card networks, ACH, wire transfers, and international payment systems
  • Embedded finance — Adding financial features to non-financial products, from payroll to marketplaces to vertical SaaS
  • Compliance tools — KYC/AML workflows, transaction monitoring, suspicious activity reporting, and regulatory filing automation

Security & Compliance

Financial software needs more than basic security. The threats are more sophisticated. The consequences of failure are more severe. The regulatory scrutiny is more intense.

Our security approach:

  • PCI-DSS compliant architecture — For any system that touches card data, we design for compliance from the start. Scope minimization, network segmentation, encryption, access controls, and logging that satisfies QSAs.
  • SOC 2 ready systems — Trust service criteria built into our development process. Security, availability, processing integrity, confidentiality, and privacy controls documented and testable.
  • Encryption everywhere — Data encrypted at rest and in transit. Key management done properly. Secrets never in code or logs.
  • Fraud detection patterns — Velocity checking, device fingerprinting, behavioral analysis, and rules engines that catch bad actors without blocking good ones.
  • Comprehensive audit logging — Every action tracked, timestamped, and attributed. Immutable logs that satisfy auditors and enable forensic analysis.

We’ve been through PCI audits. We’ve supported SOC 2 examinations. We’ve answered security questionnaires from major banks. We know what auditors look for and we build systems that pass.

Technical Approach

Financial systems need special technical care. The patterns that work for other domains don’t always work when money is involved.

Key technical principles we follow:

  • Idempotency — Operations that are safe to retry. Every payment, every transfer, every ledger entry designed so that network retries and system failures don’t create duplicate transactions.
  • Eventual consistency — Handling distributed transactions correctly. Understanding when immediate consistency is required and when eventual consistency is acceptable. Designing reconciliation processes that catch and correct discrepancies.
  • Decimal precision — Money calculations that don’t lose cents. No floating point for financial math. Ever. Proper rounding rules. Currency-aware calculations.
  • Audit trails — Every change tracked and attributed. Who changed what, when, and why. The ability to reconstruct the state of any account at any point in time.
  • Failure handling — Graceful degradation when downstream systems fail. Clear error states. No stuck transactions. No silent failures.

These patterns aren’t optional. They’re the difference between a fintech product that works and one that loses money.

Integration Experience

We’ve worked with the major players in the financial infrastructure ecosystem:

  • Payment processors — Stripe, Adyen, Braintree, legacy processors, and direct card network connections
  • Banking APIs — Plaid, MX, Yodlee, Finicity, and direct bank integrations
  • Payment rails — ACH (same-day and standard), wire transfers, RTP, FedNow, card networks, and international payment systems
  • Accounting systems — QuickBooks, Xero, NetSuite, and general ledger integrations
  • Regulatory reporting systems — CTR filing, SAR filing, 1099 reporting, and state-specific reporting requirements
  • Identity verification — Document verification, database checks, biometric verification, and fraud screening services

Integration is where fintech projects often go wrong. Edge cases multiply. Failure modes compound. We’ve seen the problems and we know how to avoid them.

Fintech is unforgiving. But the opportunity is massive. If you’re building financial technology that needs to work the first time, we should talk.

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