DEV.co
Fintech Software Development

Software Development for Finance

We're a fintech developer's fintech developer — senior engineers building secure, compliant financial software for banks, lenders, payment companies, wealth platforms, and trading firms. Built to clear PCI DSS, SOC 2, and KYC/AML from the first commit.

PCI DSS · SOC 2 · KYC/AML · PSD2 / Open Banking · GLBA · GDPR
$1T+
Global fintech market we build for
PCI · SOC 2
Compliance engineered in by default
10+ yrs
Building financial software
100%
Senior, in-house engineering teams

A financial software development company built for FinTech.

Fintech is one of the fastest-growing sectors on earth — pushed forward by data analytics, blockchain, cloud, and AI. The opportunity is enormous, and so is the bar: regulated, security-critical software that can't afford to be wrong.

If you run a finance business today, the wake-up call is simple — adapt to new technology faster than ever, and pick a development partner who understands money, not just code. Off-the-shelf tools force you to jam square pegs into round holes; financial institutions have unique workflows, compliance obligations, and data that demand bespoke financial software.

That's where a dedicated fintech software development company earns its keep. We build custom, best-fit solutions for the way your institution actually operates — turning large volumes of financial data into efficiency, insight, and a defensible position in an increasingly digital financial industry.

What our fintech developers build.

Full-stack financial software across the products that move money — engineered for security, auditability, and scale.

Banking

Core Banking & Ledgers

Double-entry ledger systems, account and balance engines, digital banking apps, and core-banking integrations with reconciliation built in.

Payments

Payments & Card Issuing

Payment processing, ACH and wire flows, card issuing and acquiring, wallets, and PCI-compliant tokenization across rails and providers.

Credit

Lending & Underwriting

Loan origination, automated underwriting and credit decisioning, servicing, and BNPL platforms with risk models baked in.

Wealth

Wealth & Robo-Advisory

Portfolio management, robo-advisors, expense and budgeting tools, and financial-reporting platforms for advisors and consumers.

Markets

Trading & Brokerage

Order management, real-time market data, brokerage and exchange systems, and low-latency pipelines for balances and risk.

RegTech

RegTech, KYC/AML & Fraud

KYC/AML onboarding, transaction monitoring, fraud detection, and regulatory-reporting automation for audit-ready operations.

Security & compliance first

Few industries have a higher bar for data security. We build to it.

The financial world's data-security requirements are among the strictest anywhere — and a single lapse can be existential. We design security and compliance into the architecture rather than bolting them on afterward.

That means PCI DSS for card data, SOC 2 controls for operations, and the regimes that apply to your market — KYC/AML, PSD2 and open banking, GLBA, and GDPR/CCPA — backed by tokenization, end-to-end encryption, least-privilege access, immutable audit logs, and segregation of duties.

Review Your Compliance Needs
Show, don't tell

Money moves on an auditable, double-entry ledger.

Every transaction balances to zero and is recorded immutably — the foundation of any trustworthy financial system.

ledger.tstypescript
// Double-entry transfer: debits must equal credits, alwaysasync function transfer(from: Account, to: Account, amount: Money) {  assert(amount > 0 && from.balance >= amount)   // no overdraft, no negatives  return ledger.atomic(async (tx) => {    tx.post({ account: from, debit: amount })     // -X    tx.post({ account: to,   credit: amount })    // +X    tx.requireBalanced()                          // sum(entries) === 0    await audit.record(tx, { actor, ip, traceId }) // immutable trail  })}
Posting result
txn 4f9c → balanced ✓
debit acct_from −$1,250.00
credit acct_to +$1,250.00
audit immutable · SOC 2 trail ✓

Atomic, balanced, and audited — the same discipline we apply to payments, lending, and trading flows.

How a fintech build runs.

A disciplined process that respects how regulated, money-handling software has to be delivered.

01

Discovery

Map the product, the money flows, the regulatory surface, and the integrations — banking cores, payment rails, KYC/AML and data providers.

02

Architecture

Design for security, auditability, and scale: data model, ledger, threat model, and compliance controls before a line of feature code.

03

Build

Senior engineers ship in tight iterations with automated tests, code review, and reconciliation built into every money path.

04

Harden & certify

Security testing, penetration tests, and the evidence trail your PCI DSS, SOC 2, and audit obligations require.

05

Launch & evolve

Zero-downtime deploys, monitoring of transactions and risk, and a roadmap to keep the platform compliant and competitive.

In-house hire vs. a DEV.co fintech team.

Why most financial-tech firms partner instead of building an engineering org from scratch.

Hiring in-houseDEV.co fintech team
Time to first shipMonths of recruitingWeeks — team is ready
Fintech & compliance depthHard to find, harder to keepBuilt-in across the team
Security / PCI / SOC 2You build the practiceEngineered in by default
Scaling up or downSlow, costly headcountFlex the team to the roadmap
Total cost over timeSalaries, benefits, churnPredictable, project-based

Compliance & standards we build to.

The frameworks and regulations that govern financial software — handled as first-class requirements.

PCI DSS

Cardholder data tokenized, encrypted, and scoped to shrink your compliance burden.

SOC 2

Operational controls, logging, and evidence trails auditors expect to see.

KYC / AML

Identity verification, sanctions screening, and transaction monitoring.

PSD2 / Open Banking

Secure, standards-based APIs for account access and payment initiation.

GLBA

Safeguards for nonpublic personal information across the stack.

GDPR / CCPA

Privacy-by-design, consent, and data-subject rights handled correctly.

SOX-ready

Controls and audit trails that hold up to financial-reporting scrutiny.

Encryption

End-to-end encryption in transit and at rest, with managed key rotation.

Why DEV.co

A partner that treats your financial software like its own.

We take pride in developing custom software for financial-services companies — whether you have a specific product in mind or want our team to help shape applications that let you grow and compete.

When you work with us, you get security that counters the threats finance faces, reliability proven through rigorous testing, and maintainable code written to the golden rules so your platform stays nimble and modern for years.

Tell Us About Your Project

What you get with DEV.co.

  • Senior financial software developers — no junior hand-offs; the people who design your system build it.
  • Security and compliance by default — PCI DSS, SOC 2, and KYC/AML treated as requirements, not afterthoughts.
  • Auditable, reconciled money flows — double-entry ledgers and immutable trails on every transaction path.
  • Clean integrations — payment, banking, and data providers behind swappable, well-tested APIs.
  • Modernization without downtime — incremental migration that keeps you processing the whole time.
  • Maximum ROI — a fintech focus that delivers value and return at every step.

Ways to engage.

From a focused discovery to a long-term product partnership.

Fintech Discovery
1–3 weeks
from $12,000
  • Product & money-flow mapping
  • Architecture & threat model
  • Compliance & integration roadmap
  • Effort + cost estimate
Start a Discovery
Product Build
ongoing
from $50,000
  • Dedicated senior fintech team
  • Secure, compliant build
  • Payment & banking integrations
  • Audit-ready from launch
Build Your Platform
Modernize / Scale
project
custom
  • Legacy system modernization
  • Zero-downtime migration
  • Performance & scale work
  • Ongoing compliance support
Discuss Modernization
The bottom line

There are plenty of software development services — but few that live and breathe finance. Our focus on FinTech means you get top value and maximum ROI at every step, on software your customers and regulators can trust.

Fintech development questions.

What does a fintech developer at DEV.co actually build?
Our fintech developers build the full range of financial software: core banking and ledger systems, payment processing and card issuing, lending and underwriting platforms, wealth and robo-advisory tools, trading and brokerage systems, and regtech for KYC/AML, fraud, and reporting. Every build is engineered around security, auditability, and regulatory compliance from day one.
How do you handle financial compliance and data security?
Security and compliance are designed in, not bolted on. We build to PCI DSS for card data, SOC 2 controls for operations, and the requirements that apply to your market — KYC/AML, PSD2 and open banking, GDPR/CCPA, and GLBA. That means tokenization of sensitive data, encryption in transit and at rest, least-privilege access, immutable audit logs, and segregation of duties baked into the architecture.
Should we build financial software in-house or outsource it?
Senior fintech engineers who understand both modern architecture and financial regulation are rare and expensive to hire and retain. Partnering with a dedicated financial software development company gives you that expertise on demand, frees your internal team to focus on the product and the market, and typically lowers total cost over the life of the system while shortening time to launch.
Can you integrate with banking, payment, and market-data providers?
Yes. We integrate the providers fintech runs on — Stripe, Adyen, Plaid, Marqeta, Dwolla, ACH and wire rails, card networks, core-banking cores, custodians, and market-data and KYC/AML vendors — behind clean, well-tested API layers so a provider can be swapped without rewriting your product.
Do you build with blockchain, AI, and real-time data?
When they earn their place. We build smart-contract and tokenization systems where on-chain settlement adds real value, machine-learning models for fraud detection, credit decisioning, and personalization, and streaming pipelines for real-time balances, risk, and trading. We won't add a technology that increases your regulatory or operational risk without a clear payoff.
How do you keep a financial platform live while you modernize it?
We migrate legacy financial systems incrementally rather than with a risky big-bang rewrite — standing up new services alongside the old, routing capabilities across one slice at a time with reconciliation and parity tests, and decommissioning legacy pieces only once the replacement is proven. You keep processing transactions the entire time.

Let's build your fintech platform.

Tell us about the financial software you need — we'll map a secure, compliant path from idea to launch.