Wallet Core (@interop/wallet-core)

Shared wallet-domain logic (WAS sync engine core and wallet Space layout contracts) for Interop wallet apps.

Table of Contents

• Background
• Install
• Usage
• Contribute
• License

Background

@interop/wallet-core is the shared, correctness-critical code two WAS-enabled wallet apps (a React Native mobile wallet and a browser wallet) hold in common: the cross-replica byte-compatibility surface both must agree on to converge on identical bytes. It is isomorphic (browser, Node.js, React Native) and has no UI or storage dependencies -- side effects are injected, and the dep-heavier protocol subpaths are import-directly-only.

The subpaths:

• @interop/wallet-core/sync -- the Wallet Attached Storage (WAS) replication engine core: the SyncEngine orchestration (single-flight, migrate-once, backoff), the runPull / runPush algorithms, the replica-side SyncStore seam, and the generic SyncedCollectionSpec shape. The wire contract and port (WasSyncPort, WireDoc, DocCipher, ...) are re-exported from @interop/was-client so an engine consumer imports one package.

• @interop/wallet-core/space -- the wallet Space layout contract: the shared collection ids and descriptive specs (private-credentials, public-credentials, wallet-activity), the wallet-activity wire shape with its pure addHistory* payload builders, the publicCredentialUrl derivation, and the was-link QR hand-off contract. Contacts collection specs live in @interop/social-core.

• @interop/wallet-core/identity -- the WAS identity derivation both wallet apps must perform byte-for-byte identically: agentsFromSecret / agentsFromSeed (controller secret or 32-byte seed to the did:key CapabilityAgent, ZcapClient, X25519 key agreement key, and single-key resolver, under the fixed bootstrap handle / key name) and singleKeyResolver.

• @interop/wallet-core/request -- wallet-request / exchange protocol handling: request classification and parsing (CHAPI get/store events, wallet-api messages and URLs), QueryByExample matching, cryptosuite negotiation, composeVp (signer and holder injected), the pure processRequest (consent runs in the caller; zcap / App Connect processing injected), the VC-API exchange client, and VCALM interaction: URL handling. The VPR type vocabulary lives in @interop/data-integrity-core and is re-exported here.

• @interop/wallet-core/display -- pure verifiable-credential derivation / display helpers and credential input parsing. Raw values out (ISO strings, Date, booleans); date formatting, i18n, and UI concerns stay in the app.

• @interop/wallet-core/webvh -- the account's did:webvh identity: the hosted DID log, its per-client update-key rotation, the client enrollment entries, the one-entry client-revocation edit (verification methods, update key, and standing commitments out in a single entry, the staged commitment recovered by log attribution), the enrolled-client listing over a caller-verified log (for a "your wallets" surface), and ZCap signing under the did:webvh verification-method id.

• @interop/wallet-core/keys -- the per-user key (PUK) and its key-map/puk.json wrap-set roster: minting, the roster's init/read/rotate primitives with their client-side guards (epochsMac, the latest-seen epoch pin, the document-backed recipient resolver), the roster's compare-and-swap descriptor store, and the PUK rotation cascade's per-collection op (re-epoch a collection onto the roster's current PUK, staleness detected from durable state alone, history escrowed -- also the completion sweep's building block). Also the enrolled-client display labels (key-map/client-labels.json).

• @interop/wallet-core/descriptors -- collection encryption-descriptor acquisition (fetch / cache / offline fallback) and the unknown-epoch refresh policy, including a self-refreshing EDV document cipher.

• @interop/wallet-core/keyring -- the unlock layer: the unlock derivation, the { version, wrapped } account-pointer record codec, and the unlock Space lifecycle.

• @interop/wallet-core/enrollment -- the client enrollment ceremony (connect code, approval, completion).

• @interop/wallet-core/recovery -- recovery codes on the roster identity model: a code as a minimal always-enrolled wallet client (format and derivation, the recovery record, the document half of issuance / revocation / recovery).

Install

• Node.js 24+ is recommended.

pnpm install @interop/wallet-core

Development

git clone https://github.com/interop-alliance/wallet-core.git
cd wallet-core
pnpm install

Usage

import { SyncEngine, runPull, runPush } from '@interop/wallet-core/sync'
import {
  PRIVATE_CREDENTIALS_COLLECTION,
  publicCredentialUrl,
  buildWasLinkPayload,
  parseWasLinkPayload,
  addHistoryCredentialCreated
} from '@interop/wallet-core/space'

The sync and space subpaths are re-exported from the package root as well. Every other subpath (identity, request, display, webvh, keys, descriptors, keyring, enrollment, recovery) is import-directly-only, so consumers of the root never pull the signing / KMS / document-loader dependency graph.

Contribute

PRs accepted. See CONTRIBUTING.md for editor setup (Prettier, ESLint, and EditorConfig) and how it maps to CI.

If editing the Readme, please conform to the standard-readme specification.

License

MIT License © 2026 Interop Alliance.