By Ilya Podoynitsyn, CEO of FinHarbor
The Hidden Cost of Getting Started Fast
Launching a neobank has never looked easier on paper. Dozens of vendors promise turnkey solutions: sign a contract, plug in a few APIs, go live. Yet behind these quick starts lies a pattern that has drained the fintech industry of billions in unrealized potential. Companies that chose speed over architectural sovereignty are discovering that the most expensive part of their platform was never the license fee – it was everything that came after.
For years, the default was a bundled banking stack from a single provider. One vendor, one contract, one integration layer. But as embedded finance, cross-border expansion, and regulatory complexity accelerate in 2026, this approach has become a strategic liability.
Where Monolithic Architectures Break Down
The core promise of a monolithic platform is simplicity. In practice, that simplicity holds only until the business needs to evolve. Six months after launch, a company needs a local KYC provider for a new market or a crypto custody module. In a tightly coupled system, this requires the vendor’s involvement – a queue, their release cycle, their price. Or no feature at all.
The numbers are stark. Industry estimates suggest banks allocate 70–75% of IT budgets to maintaining legacy systems, while McKinsey notes that global banking tech spending has been growing at 9% annually – outpacing revenue growth of 4% – yet productivity gains remain elusive. A 10x Banking survey found that 55% of banks consider existing core solutions their biggest roadblock to business goals.
The regulatory dimension compounds the problem. Updating a single compliance module in a monolith triggers full regression testing. I have seen cases where a KYC provider switch froze all releases for two to three months – because every component was entangled with every other. As Deloitte emphasizes, modernization is a strategic business issue, not a technology issue.
Scalability adds pressure. During peak loads, a monolithic architecture cannot scale one module independently – the entire system goes up, multiplying infrastructure costs for a bottleneck in a single layer.
And the ultimate trap: the longer you stay, the harder it is to leave. Data structures are intertwined, logic is embedded in proprietary layers, integrations are non-standard. Migration becomes a year-long project with existential risk to a live business. Many companies simply accept the constraints.
The Rise of Modular Financial Infrastructure
Instead of a single interlocked system, modular architecture composes financial infrastructure from independent services – KYC, card issuing, IBAN management, crypto custody, payments, AML monitoring – each with its own database, API, and deployment lifecycle. They communicate through standardized interfaces, meaning any component can be replaced, upgraded, or scaled without affecting the rest.
The practical impact is immediate. A new KYC provider for a new jurisdiction means changing one adapter. The rest of the platform doesn’t register the change because the API contract remains the same. Compliance updates don’t block card processing development. Teams work in parallel.
McKinsey confirms: on modern modular architectures, new solutions ship in three to four months versus nine to eighteen on legacy systems. Forward-thinking providers – FinHarbor among them – have built this way from their first line of code. The result: full neobank deployments in four to eight weeks, against six to twelve months for monolith customizations.
Why Flexibility Became the Defining Advantage of 2026
Several converging forces have made architectural flexibility a survival requirement.
The EU’s MiCA regulation is moving into full enforcement ahead of the July 2026 deadline, with 35% of blockchain startups estimating annual compliance costs above $500,000. The UK is building its own crypto framework, the US pursues a fragmented multi-agency approach. Rigid platforms cannot adapt to this patchwork fast enough.
Embedded finance is reshaping distribution. Depending on the source, the market is valued at $100–130 billion in the mid-2020s and projected to grow at a double-digit CAGR through the decade’s end. Non-financial brands now demand white-label banking capabilities integrated into their existing stacks – something monolithic cores were never designed to support.
Cross-border expansion demands composability. J.P. Morgan projects cross-border transaction volumes growing from $194.6 trillion in 2024 to $320 trillion by 2032. A fintech operating across multiple regions needs different payment rails, identity providers, and compliance regimes – often within the same platform. Only modular systems handle this without architectural compromise.
Strategic Implications for Founders and Institutions
The shift to modular infrastructure reframes “build versus buy” into “compose and orchestrate”: selecting best-in-class components, connecting them through standardized APIs, and retaining full ownership of business logic and data.
The API-first philosophy is central. When every function – account opening, card issuance, KYC, limit management – is accessible through a documented API, the client retains architectural sovereignty. No hidden logic, no vendor-only interfaces. On-premise deployment means databases, logs, and KYC files physically reside on the client’s infrastructure, eliminating data hostage scenarios common in SaaS models.
Everything built on top – frontends, custom modules, automations – belongs to the company. The infrastructure is a foundation, not a cage.
The Next Decade Belongs to Composability
The monolithic era is ending with a gradual recognition that rigidity is incompatible with modern finance. Digital-first banks deploy features in days; legacy institutions require months or years. The innovation gap is becoming the competitive gap.
The winners of the next decade will build on composable, sovereign infrastructure – where every component evolves independently, data belongs to the operator, and switching costs trend toward zero. Not the largest bundled platform, but the most adaptable architecture wins.
This article is not intended as financial advice. Educational purposes only.
