Custom Fintech SaaS Development: PSD2 and DORA

PeakLab builds custom SaaS software for finance businesses: management platforms for advisers and brokers, invoicing and collections tools, client portals for asset management firms, applications that use banking data through open banking. We handle the project end to end from Paris: scoping, architecture, development, security (strong authentication, operation logging) and compliance with the European framework, notably PSD2 and the DORA regulation, in force since January 2025.

With more than 20 projects delivered and a 4.9/5 Google rating across 18 reviews, we work with leaders whose business is already running: a brokerage firm, an asset management company, a fintech in operation, a company whose invoicing or cash management relies on manual processes that have become unsustainable. Our job is to turn those processes into reliable, traceable, sellable software.

DORA: operational resilience is no longer optional

The European DORA regulation has applied since January 2025 to financial entities and, by extension, to their IT providers. In practice, if your SaaS serves banks, insurers or asset managers, your clients will ask for contractual guarantees: incident management, resilience testing, business continuity, third-party risk control. We design finance SaaS with these requirements in mind: usable logs, tested backups, documented recovery procedures. This has become a purchasing criterion for your regulated prospects, not a technical detail.

PSD2: strong authentication and access to banking data

PSD2 mandates strong customer authentication (SCA) for account access and sensitive operations, and regulates access to banking data through dedicated APIs. For a SaaS that aggregates accounts, initiates payments or displays banking data, this translates into precise architectural choices: systematic two-factor authentication, consent management, connecting to banking APIs directly or through a licensed aggregator. We make that call with you based on your volume, budget and timeline.

What these projects have in common: they start from a process that already exists in your company and works, but relies on people, spreadsheets and email threads. The software does not reinvent your business; it makes it reliable, lets it handle growth and, in some cases, makes it sellable to your peers.

The trajectory we see most often with our clients: a tool built first for internal use that saves the teams several hours a week, then catches the attention of peers facing the same problem. At that point the question changes in nature: it is no longer about cutting a cost, but about creating a second revenue stream. That shift succeeds when the technical foundations (multi-account management, billing, strict data separation between clients) were laid in the first version. This is exactly what we anticipate during scoping, even if you do not plan to commercialise right away.

In finance, a breach does not only cost data: it costs your clients' trust and sometimes your ability to operate. Here is the foundation we apply to every finance SaaS, without exception, because it is far cheaper to build from day one than to retrofit after a client audit.

Specialised vendors cover standard needs well: accounting, payroll, financial CRM. If your need fits those boxes, we will point you to them. Custom development is justified when your process is a differentiator, when market tools impose their limits on you (no exports, locked-in data, per-user pricing that spirals) or when you want to turn in-house expertise into a product sold by subscription. The real question is not the cost of development, but what double data entry, manual errors and dependence on a vendor you do not control cost you every month.

A first usable version of a finance SaaS is generally built in three to six months, depending on the scope, the banking integrations and the level of requirements of your end clients. The budget runs into tens of thousands of euros for a serious product: security, audit trails and banking integrations represent a real share of the effort, and neglecting them upfront always costs more later in compliance work. We quote precisely after a scoping phase, never before, and we tell you if part of the need is better served by an existing tool.

Three factors move the quote the most in this sector: the number of external integrations (banks, accounting tools, payment providers), the level of guarantees your end clients require (a product sold to consumers and a product audited by a bank's risk department do not demand the same effort), and the scope of the first version. Trimming that scope is the most effective lever to control the budget without sacrificing quality: we would rather ship one complete, secure, billable journey and then expand, than build everything at once.

You work directly with the founders, Lucien Arbieu and Fahari Hamada, and with the team that codes your product. An initial scoping phase translates your business process into specifications, deliveries land every two to three weeks on a test environment, and we stay involved after launch for evolutions, monitoring and your clients' security questionnaires. That continuity is what our 4.9/5 Google rating reflects.