CodeSampleX

Sample

verify pkg:npm/cookie-signature@1.2.2

sha256:5a9400f0796dc83957921d83e1eea8f6054d4c32a6d9d991342d1fd71dd76b1b

Publication state. LOCAL_PASS passed only on its author's machine; PUBLISHED is public and awaiting independent verification; CROSS_PASS was reproduced by another verifier; MATRIX_PASS passed across environment boundaries; STABLE has sustained independent passes without recent failures. Evidence strength. L0 is source only; L1 resolved dependencies; L2 compiled or loaded; L3 passed its contract; L4 was independently reproduced; L5 passed across different environments. MIT-0

Execution evidence

Declared environment and signed verification runs are separated so you can see exactly what this sample proves.

Evidence basis
Independent cross-verification
Verification receipts
1
Verification level
L4_CROSS_PASS
Declared environment linux 24 · ubuntu · glibc 2.39 x64 npm

Verification-run environments

Environment Contract Stages Run
node 22 · linux alpine/x64 · docker ed25519:c1973797be207ac4 PASS compile:SKIPPED · contract:PASS · load:PASS · resolve:PASS
CONTAINER_RUN · node-typescript@1
2026-08-20

Case

HOW
Goal
verify pkg:npm/cookie-signature@1.2.2
Packages
Created
2026-08-20T13:43:52Z

Contract

  1. assert cookieSignature.sign signs cookie string value with HMAC SHA256 base64 digest stripped of padding
  2. assert cookieSignature.unsign recovers the original cookie value when secret matches
  3. assert cookieSignature.unsign returns false for tampered payload or mismatched secret
  4. assert cookieSignature.sign and cookieSignature.unsign throw TypeError when argument types are invalid or secret is null

Files

  • PROMPT.md
  • csx.json
  • package-lock.json
  • package.json
  • spec.json
  • test/contract.mjs

Download the source artifact (tar.gz)

Origin Seeder

anonymous