Financial systems built around trust
Design transaction records, account workflows, and migration plans around correctness, continuity, and clear operational control.
Focus
Financial operations
Verify
transaction records
Protect
access boundaries
Plan
safe transitions
Chapter 01
The problem space
Financial software has to make balances explainable, changes traceable, and failure recovery deliberate. Replacing part of an existing system adds another constraint: the people using it still need to work throughout the transition.
Chapter 02
Design priorities
Map financial invariants and reconciliation rules before selecting the architecture. Separate ledger responsibilities from customer journeys, define access boundaries, and plan migration checkpoints with the teams responsible for daily operations.
Chapter 03
System architecture
A transaction ledger, explicit service boundaries, and auditable event records provide a foundation. Reconciliation tools, controlled releases, and a staged migration can help teams verify each transition before moving more activity.
Chapter 04
What to measure
Evaluate reconciliation accuracy, transaction traceability, recovery procedures, and the effort needed to investigate an exception. Availability and performance targets belong in the agreed scope and should be checked against representative workloads.
Technology stack
The tools we reached for.
- Go
- Kotlin
- PostgreSQL
- Kafka
- Kubernetes
- Datadog
- React Native
- Terraform
“A migration plan should make account balances verifiable at every step.”
A design priority
Invanolabs / Engineering
Good engineering starts by deciding what matters.