Durable Financial Operations
Network partitions destroy sagas. We run financial workflows on a durable execution engine. If a pod crashes mid-transfer, the state machine resumes exactly where it failed.
Idempotency keys and retry loops are insufficient for multi-step bank integrations. Fernel provides a programming model where transient errors are swallowed by the engine.
Code executes as if the network is perfectly reliable. State is persisted automatically at every await point.
No partial states exist. Every financial operation correlates to a unique workflow ID, satisfying DORA Article 11 traceability requirements out of the box.
Workflow Capabilities
Exactly-Once Execution
Every workflow step runs exactly once, even across process restarts. No duplicate transactions. No skipped steps.
Automatic Compensation
When a step fails permanently, the workflow reverses previous steps in the correct order. Ledger debits are reversed. Notifications are sent.
Long-Running Processes
Workflows can wait for external events (KYC result, settlement confirmation, R-transaction) without consuming resources. Wake on event or timeout.
Audit Correlation
Every workflow has a unique ID. Every step is logged with this ID. Auditors can trace a complete financial process from a single identifier.
How It Works
// Account Creation Workflow (4 durable steps)
//
// Step 1: Create customer record in finance service
// Step 2: Provision ledger accounts (EUR, USD)
// Step 3: Assign IBAN via banking partner
// Step 4: Trigger KYC verification session
//
// If step 3 fails:
// steps 1-2 are compensated
// (accounts closed, record archived)
//
// If step 4 fails:
// account created but flagged as pending-kyc
// (non-blocking)Technical Specifications
| Execution model | Durable, journaled, exactly-once |
| Failure handling | Automatic retry (transient), compensation (permanent) |
| State persistence | Write-ahead journal, survives process restarts |
| Correlation | Workflow ID propagated to every downstream call and audit entry |
| Implemented workflows | Account creation, FX rate refresh, KYC verification |
| Integration pattern | Write gateway: all state-changing operations route through workflows |
| Regulatory alignment | DORA Art. 11-12 (ICT traceability), full recovery capability |
Workflows That Always Complete.
Talk to our team about your workflow orchestration requirements.