ConnectPay has completed the transition to its proprietary core banking system, Mars, removing its dependency on third-party core infrastructure.
Following this announcement, Lithuania-based ConnectPay has migrated to a fully in-house core banking platform named Mars, placing it among the European fintechs that own and operate their core financial infrastructure. The move eliminates what the company describes as the single largest external dependency an EMI can carry: reliance on a third-party core banking provider.
Core banking systems serve as the foundational layer for account balances, transaction processing, and payments. The majority of fintechs source this layer from specialist vendors, accepting a degree of operational dependency in exchange for reduced build complexity. ConnectPay's decision to develop Mars internally reflects a different calculation — one that prioritises resilience, control, and long-term cost structure over speed to market.
Resilience and speed of delivery
According to the official press release, the operational case for in-house ownership centres on two factors: uptime control and product velocity. When an external core banking provider experiences disruption, the downstream impact reaches clients immediately. By owning the infrastructure, ConnectPay can manage incidents directly and resolve issues without waiting on a third-party response chain.
Beyond stability, the transition affects how quickly ConnectPay can iterate on its product. Under a third-party model, changes to core functionality depend on the vendor's release schedule and prioritisation. With Mars operational, the company states it can implement product changes and respond to regulatory requirements within weeks rather than months.
The regulatory dimension is becoming more pressing across the sector. The EU has mandated that all payment service providers support instant payments by the end of 2025, a requirement that places infrastructure flexibility at a premium. According to figures cited in the announcement, instant SEPA payments are projected to account for 18% of all European payments by 2035, up from a fraction of that today.
A capital-intensive undertaking
Building a proprietary core banking system is widely regarded as one of the more demanding technical and regulatory undertakings in fintech. It requires sustained engineering investment, the ability to manage systemic risk, and alignment with applicable regulatory standards — conditions that lead most fintechs to avoid the build path entirely.
The financial logic also shifts over time. By removing external core licensing fees, ConnectPay indicates that in-house ownership creates structural cost advantages that may eventually translate into pricing for clients.
ConnectPay's positioning reflects a broader tension emerging in European fintech: as resilience standards rise and embedded finance deepens, the question of whether infrastructure ownership confers competitive advantage is becoming more material. For now, fintechs that have taken this step remain a minority.
