Category definition
Why Portable Trust Infrastructure Exists
Identity, payments, and credit answer important questions — but not how trust signals move responsibly across ecosystems. PTI is the missing infrastructure layer.
The problem
Trust in digital systems is fragmented.
- Credibility built with one lender stays with that lender
- Rental history rarely reaches the next landlord
- Community and informal economic activity is invisible to formal decision systems
- Each institution rebuilds identity resolution, event schemas, scoring, consent, and audit from scratch
People repeatedly prove themselves. Organizations duplicate trust infrastructure instead of sharing interoperable semantics.
TumiTrust is a reference implementation of PTI — production infrastructure for institutions, trust producers, and individuals — not a consumer credit-score product.
Existing layers
Digital infrastructure matured in partial answers:
| Layer | Question answered |
|---|---|
| Identity | Who are you? |
| Authentication | Can you access this session or resource? |
| Payments | Can value move? |
| Credit systems | What formal financial history exists? |
| Reputation systems | What do others think on this platform? |
Each solves a real problem. None answers the cross-cutting institutional question:
How can trust signals move securely and responsibly across digital ecosystems?
The missing layer
Portable Trust Infrastructure (PTI) is that missing infrastructure layer.
PTI separates trust production (partners and institutions emitting verified activity) from trust consumption (decision-time lookups with explainability). It assigns portable subject identity (pti_id), isolates life-area contexts, and preserves provenance so outcomes are auditable — not opaque scores.
PTI is not:
- A credit bureau replacement
- A single opaque score product
- A single vendor wallet
- A social rating app
PTI is a specification for how trust intelligence can be produced, exchanged, resolved, and consumed under governance — by any compatible implementation. Optional compliance screening can sit alongside PTI; it does not redefine the category as a traditional BGC bureau.
What changes with PTI
| Without PTI | With PTI |
|---|---|
| Trust trapped in silos | Context-scoped signals portable across institutions |
| Opaque scores | Explainable outcomes with evidence chains |
| Repeated KYC and re-proof | Persistent pti_id with governed lookups |
| Ad hoc integrations | Normative event and lookup contracts (RFCs) |
Traditional vs PTI model
Continue reading
| Topic | Link |
|---|---|
| Historical foundation | PTI Origin |
| Design principles | Core design principles |
| Architecture stack | Trust infrastructure stack |
| Normative specification | PTI Specification v1.0 |
| Build a compatible system | Build Your Own PTI |
| Reference implementation | TumiTrust |
| Get started on the platform | Get started |
Also see Problems with existing systems for detailed comparisons.