Disclosure: RBB LAB is also an investor in BlockInvest.
Non-performing loans sit in a corner of finance that most software ignores: opaque, heavily documented, and awkwardly positioned between legacy banking systems and modern regulatory expectations. BlockInvest set out to change that by bringing the full lifecycle of NPL instruments onchain, giving every party in the chain a single, timestamped, auditable view of the instrument from origination to resolution.
RBB was appointed to build the initial release of the platform and, separately, to help BlockInvest assemble and evaluate its internal engineering team.
The brief
The platform needed to handle three specific types of NPL instruments, each with its own structure, documentation requirements, and regulatory presentation. The core problem was normalization: instruments arriving from different originators in different formats had to be presented consistently, legibly, and in a way that a professional investor could act on without interpretation.
- Onchain provenance. Every document associated with an instrument timestamped on-chain. The record is immutable; the audit trail is not a report, it is the ledger.
- Full lifecycle. Onboarding and KYC through to instrument issuance and acquisition: a single platform, not a patchwork of tools.
- Project tracking. Each instrument has a living project record: status, counterparties, documents, and events in one place.
The build
The backend is Ruby on Rails with PostgreSQL. The choice was deliberate: a regulated fintech platform with complex domain logic benefits from the expressiveness of ActiveRecord and the maturity of the Rails ecosystem for things like background jobs, audit logging, and PDF generation. The frontend is React.
The most interesting design challenge was the presentation layer. NPL instruments are dense: dozens of fields, multiple document types, counterparty hierarchies. Getting that into a form that is both complete for compliance purposes and usable for an investor required close collaboration between engineering and domain experts.
The hardest part was not the blockchain integration. It was deciding what the presentation of a non-performing loan should feel like to someone who has to make a decision about it.
Engineering notes
- Onchain document timestamping integrated into the instrument issuance flow, not a bolt-on, but a first-class step in the lifecycle that the platform enforces.
- A KYC and onboarding pipeline that gates instrument access; investors cannot see or acquire instruments until their profile is complete and approved.
- A MiFID2-compliant investor questionnaire built into the onboarding flow. The questionnaire adapts dynamically based on the customer qualification type: the questions, requirements, and thresholds presented to a large corporation are different from those presented to a financial institution or a professional investor. Compliance is structural, not a checkbox at the end.
- A normalised data model for three distinct NPL instrument types, each with its own field schema, document requirements, and status lifecycle, all rendered through a shared presentation layer.
- Project tracking tied to each instrument: every status change, document upload, and counterparty action recorded and visible to authorised parties.
The result
The initial release shipped on schedule. BlockInvest has continued developing the platform with its in-house team. Our second contribution was helping them build that team: evaluating candidates, advising on team composition, and making sure the people who took ownership of the codebase were equipped to carry it forward.
Team building
Handing off to an in-house team is only clean if the team is right. We worked alongside BlockInvest through the hiring process: reviewing technical profiles, conducting evaluations, and advising on the shape of the engineering organisation they needed at that stage of the company. This is work we do not advertise loudly, but it is some of the most consequential we do.