1 WE BUILD Conformance Specifications (WBCS)

1.1 About

The WE BUILD Conformance Specifications (WBCS) define how WE BUILD participants implement wallet interfaces and communication protocols between issuers, wallets, and relying parties. They ensure interoperability and conformance by translating ADR decisions into precise implementation requirements.

The ITB will be based on the WBCS as a starting point. The test suites in the ITB are relying predominantly on the WBCS.

1.2 Contributing

The Architecture group define the WBCS, with help from all implementing participants. Propose new WBCSs using the template.

1.3 CS Process Summary for WE BUILD Large Scale Pilots (LSPs)

---
config:
  flowchart:
    defaultRenderer: 'elk'
    subGraphTitleMargin:
      bottom: 25
---

graph TB
%% flowchart

    subgraph "WP4 (Architecture)"
        Proposal -- Discuss --> Review
        Review -- Rejected --> Proposal
        Review -- Approved --> WBCS
    end

    subgraph "Participants from WP2, WP3 and WP4"
        Implementations["Implementations
        (wallets, issuers, verifiers)"]
    end

    subgraph "Testing Group"
        ITB["ITB"]
    end

    WBCS -- "Guiding" --> Implementations
    WBCS -- "Configure" --> ITB
    Implementations -- "Test" --> ITB

    Anyone -- "Create/adapt" --> Proposal
    SpecEfforts["Specification efforts"] -- "New wallet interface definitions" --> WBCS
    TestDev["Test development"] -- "New version test cases" --> ITB

1.3.1 Approved WBCS

WBCS # WBCS Title
CS-001 Credential Issuance - v1.1
CS-002 Credential Presentation - v1.0
CS-003 Remote Qualified Signing with Wallet Units - v1.0
CS-004 Individual Wallet Unit Attestation (WUA) Lifecycle - v1.1
CS-005 Business Wallet Unit Attestation (BWUA) Lifecycle - v1.1
CS-007 Credential Presentation and Issuance via the Digital Credentials API
CS-010 Revocation Mechanism - v1.1
CS-012 SCA Attestations for Payment Transactions (TS12 Profile) - v1.0
CS-015 QERDS - EBW Interface - v1.0

1.3.2 WBCS Under Development

WBCS # WBCS Title Status Priority Target Date
CS-006 Issuance of WRPAC/WRPRC 🟢 In review Must-have Oct 2026
CS-011 Remote QESeal creation 🟢 In review Must-have Oct 2026
CS-013 Intermediary services pre-flight 🟢 In review Must-have Oct 2026
CS-014 Proximity / Offline profile 🔵 Investigating Should-have Nov 2026
CS-016 Inter-QTSP Message Relay (QeRDS AS4) 🟢 In review Low Aug 2026
CS-017 Directory & Discovery (EDD) 🔵 Investigating Must-have Oct 2026
RP-QERDS interface 🟣 Candidate Low Jan 2027
Support for Data spaces 🟣 Candidate SC2 specific Jan 2027

1.3.3 Status Definitions

Status Description
Not started No active work has started yet.
Investigating The topic is being investigated and potential approaches are being evaluated.
Drafting The specification is being drafted.
In review A concrete draft exists and is under review.
On hold Work has been temporarily paused.
Dropped The specification will not be taken forward.