Side-core deployment
What is side-core banking?
Side-core is a deployment architecture in which a modern core banking platform operates alongside an incumbent core, allowing institutions to move selected products, workflows, or capabilities without requiring immediate full-core replacement.
With Nucleus BankOS, you can validate workflows, controls, data, and economics on real operations — and migrate on your own timeline instead of in one high-stakes cutover.
How it works
One experience for customers. Two cores, kept in sync.
Customers keep banking at your URL. New products and workflows run on Nucleus BankOS, while every transaction still settles on your incumbent core — and is written to Nucleus at the same time.
your customers · your domain
runs in production, alongside your core
system of record · authoritative
Transaction flow
A customer transacts through a Nucleus product at your URL.
Product logic runs and writes to the Nucleus ledger — a complete, modern record.
The transaction is written to your incumbent core in real time, so it stays authoritative.
Change-data-capture keeps both cores aligned continuously — not at a cutover.
What you can run in side-core
A real operating platform — not a sandbox.
Side-core isn’t a limited pilot. Most of what makes Nucleus BankOS a full bank operating system runs alongside your existing core, in production.
No-code product deployment
Launch and change deposit, loan, and servicing products with no-code configuration — across both onboarding and servicing — without waiting on the incumbent core’s release cycle.
Nucleus BankOSFraud, cyber, BSA & AML (DarkMatter)
Run DarkMatter’s fraud, cyber, BSA, and AML controls on the activity the platform can see. Transactions flowing through Nucleus are monitored in real time; activity still settled on your incumbent core is analyzed on synced data — near-real-time rather than instantaneous — until those flows move onto the platform.
Honest about real-time limits
DarkMatter Synergy+Regulated digital assets (Prism)
Stand up regulated digital-asset and stablecoin operations on the same ledger, identity, and compliance foundation — without touching your existing core of record.
PrismWealth & advisory (Horizon)
Bring wealth and advisory operations onto a household-keyed relationship view that sits alongside — not inside — your incumbent core.
HorizonBaaS & embedded finance (Fabric)
Operate Banking-as-a-Service and embedded-finance programs — deposits, credit, partner programs, subledgers, controls, and APIs — under your charter, running side-core.
FabricLending (Foundry)
Originate and service loans on Foundry’s governed decision engine while your incumbent core stays in place as the system of record.
FoundryIntegration
Simple to connect. Non-disruptive by design.
Side-core requires a lightweight integration to your existing core — typically a read/sync of accounts and transactions. It’s intentionally simple, and it does not disrupt day-to-day operations.
- Your incumbent core keeps running as the system of record.
- No forced cutover, no rip-and-replace, no big-bang migration.
- Move selected products and workflows onto the platform when you’re ready.
- Validate lower TCO, vendor consolidation, and customer-journey operations before a full-core decision.
Side-core, in plain terms
- What is side-core banking?
- Side-core is a deployment architecture in which a modern core banking platform operates alongside an incumbent core, allowing institutions to move selected products, workflows, or capabilities without requiring immediate full-core replacement.
- Does side-core disrupt my existing core?
- No. Side-core requires a lightweight integration to your existing core — typically a read/sync of accounts and transactions. Your incumbent core keeps running as the system of record; there is no forced cutover and no rip-and-replace.
- Is fraud and transaction monitoring real-time in side-core?
- For activity that flows through Nucleus BankOS, monitoring is real-time. For activity still settled on your incumbent core, DarkMatter analyzes synced data, which is near-real-time rather than instantaneous. Detection becomes fully real-time as those flows move onto the platform.
- What can I run in side-core?
- No-code product deployment for onboarding and servicing, DarkMatter fraud and compliance controls, Prism digital assets, Horizon wealth, Fabric BaaS and embedded finance, and Foundry lending — all alongside your existing core.
Move forward without betting the bank.
See how side-core deployment lets your institution validate outcomes on real operations before committing to a full-core replacement.