@baerae/zkap-zkp-wasm

WebAssembly bindings for zkap-zkp.

Install:

npm install @baerae/zkap-zkp-wasm

import initZkap, { generateHash, generateAnchor } from '@baerae/zkap-zkp-wasm'

await initZkap()
const hash = generateHash(['0x1', '0x2'])

This direct runtime package exposes the wasm-pack API. Initialize the WASM module once, then call the hash helpers synchronously. Use @baerae/zkap-zkp with this package when you need the Promise-based compatibility facade.

Input/output contract

Locked by the cross-runtime golden suite (golden/anchor-vectors.json) — identical for @baerae/zkap-zkp-node.

| Item | Contract | |------|----------| | secrets ({sub, iss, aud}) | Raw strings — no quotes. The SDK wraps each claim in JSON-style "…" internally (0.1.5+ contract, forbidden padding included). Caller-side quoting double-wraps and silently changes every anchor/audHash value. | | Padding | Caller pads. generateAnchor needs exactly n secrets; deriveSelector needs exactly k (padToThree: 1 account → [s,s,s], 2 → [s1,s2,s1], 3 → [s1,s2,s3]). The SDK never pads or shuffles. | | anchorEvaluations | Exactly n − k + 1 entries (4 for 3-of-6), hex (0x…) or decimal field-element strings, in on-chain getAnchor() order. Caller slices any extra on-chain fields. | | deriveSelector return | number[] of length n, 0/1 per slot — the first slot combination (ascending C(n,k) order) whose committed values match the presented secrets in relative order. Permutations are not searched. | | Errors | Real Error instances with a stable code property (see below). Message strings are stable for legacy matching, but branch on code. |

Error codes

| error.code | Meaning | |--------------|---------| | NO_VALID_SELECTOR | Selector search exhausted — the presented secret set (identities, quoting, or relative order) does not match the anchor. | | DIMENSION_MISMATCH | Wrong cardinality: secrets ≠ k/n, or anchorEvaluations ≠ n − k + 1. | | INVALID_INPUT | A field element, claim value, or argument shape failed parsing/length validation. | | UNSUPPORTED_PLATFORM | The function is not available in this runtime (prove/verify/groth16Setup here). | | GenericFailure | Unclassified internal failure. |