Core banking & payments infrastructure

The platform your licence runs on.

BNK2 builds and operates IO2B — a BIAN-aligned, event-driven core banking and payments platform. Accounts, cards, transfers, FX, acquiring, issuing and switching, with the compliance machinery a regulated programme actually needs. You hold the licence. We provide the technology.

A core banking platform, not a demo

IO2B is a production multi-tenant core and open banking platform built as microservices around an event bus. It is designed for institutions that must evidence what happened, not merely process it — every rail is paired with the audit, reconciliation and monitoring needed to answer a supervisor.

Standards

BIAN-aligned

Implements BIAN service domains, so integration conversations start from a shared vocabulary rather than a bespoke one.

Architecture

Event-driven

NATS JetStream carries every domain event. Fail-loud by doctrine — silent degradation is treated as a defect, not a fallback.

Control

Rules engine

Per-tenant fee, limit and eligibility evaluation, versioned and centrally managed. Change a rule, not a release.

Compliance

PSD2 & SCA

Strong Customer Authentication support, AML and sanctions screening, and double-entry general ledger posting throughout.

Core modules

The banking primitives, exposed as documented REST APIs and NATS subjects.

Module

Accounts

Current, savings, business and multi-currency accounts. Available, ledger and reserved balance types with full transaction history.

Module

Cards

Card lifecycle and authorisation, aligned to the BIAN card authorisation domain.

Module

Transfers

Credit transfers and standing orders, with settlement and reconciliation built in rather than bolted on.

Module

FX & Remittance

Currency conversion and cross-border remittance flows, rate handling and downstream posting.

Module

Loans

Loan-level data, repayment posting specifications including backdated repayment, prepayment and reschedule.

Module

Ledger

Double-entry general ledger underneath every movement, so the books and the rails cannot drift apart.

API surface

Every surface is documented, versioned and available against a simulator before you touch production.

SurfaceWhat it covers
core-bankingAccounts, balances, transactions, ledger posting
walletWallet balances, holds and movements
acquiringMerchant acquiring flows and settlement
issuingCard issuing and lifecycle
switchTransaction routing between providers and rails
payoutOutbound payment execution
hsmKey management and cryptographic operations
simulatorFull sandbox for integration and certification testing
nats-subjectsEvent contracts for asynchronous integration
BIAN domain

Payment Initiation

BIAN domain

Card Authorization

BIAN domain

Fraud Evaluation

BIAN domain

Credit Rating

Beyond the rails

Moving money is the easy half. These are the services a multi-institution programme depends on to stay supervisable — and we mark honestly what is live and what is optional.

Live

Institution onboarding & KYB

Document classification and extraction, completeness gap analysis, readiness scoring, ownership and UBO graphs, review queues, automated chasing.

Live

Portfolio data exchange

CSV and API intake with versioned hard/soft validation rule packs, field-level diagnostics, re-submission workflows and full lineage per submission.

Live

Governance workspaces

An isolated workspace per institution with byte-identical schema enforced fleet-wide. Compliance cases, evidence graphs, audit programmes.

Live

Controlled document authoring

Four-eyes controlled-change review, versioned compliance documents, structured front matter and approval gates before publication.

Live

Digital signing & integrity

PAdES signatures and verification, per-signer identity verification with liveness, tamper-evident audit chains, templated signing flows.

Live

Secrets & credential custody

A dedicated vault with a typed credential ontology, full audit trail, scheduled sync to consuming services and an OIDC identity provider.

Live

AML & sanctions screening

PEP, sanctions and adverse-media screening with configurable risk matrices, alerts and thresholds. Multi-tenant by design.

Live

Continuous monitoring

Event bus with a fail-loud doctrine, scheduled-submission tracking, SLO timers, automated chase workflows and dedicated alarm streams.

Optional

Identity & biometrics

Face and voice verification, liveness detection and enrolment flows, where a programme requires consent-based signer assurance.

Who we build for

Institutions that already hold — or are obtaining — their own authorisation, and need the technology underneath it.

Banks & credit institutions

Core replacement or a parallel digital stack alongside legacy.

Payment & e-money institutions

Accounts, transfers and remittance on rails you control.

Lenders

Loan-level portfolio exchange, validation and funder reporting.

Programme operators

Multi-institution programmes needing per-tenant governance and oversight.

Regulatory status

BNK2 is a technology provider. We are not a bank.

BNK2 sp. z o.o. supplies software and technical infrastructure. BNK2 does not hold client funds, does not provide payment services to the public, does not issue electronic money, and does not carry on banking activity.

Where the IO2B platform is used to deliver regulated services, those services are provided by the client institution under its own authorisation, and that institution remains responsible for regulatory compliance towards its customers and its supervisor.

Nothing on this site is an offer of banking, payment or investment services, and nothing here should be read as a statement that BNK2 holds any authorisation, licence or registration to provide them.

Talk to an engineer

Technical evaluations start with the simulator and the API reference, not a slide deck.

Enquiries

[email protected]

Integration questions, platform evaluation, deployment models.

Company

BNK2 sp. z o.o.

ul. Piotrkowska 116/52, 90-006 Łódź, Poland
KRS 0001132301  ·  NIP 7252347907  ·  REGON 529903161