CodeSampleX

Sample

verify hkdf in pkg:golang/golang.org/x/crypto@v0.54.0

sha256:3decb01fc7af1089a9fd05af1703feee79795c7b0eaa1bd37a1e8bd1127859fc

This network offers one thing: a sample that builds. It ran the sample in a sandbox and kept the signed receipt. It grades nothing and warrants nothing — whether the same code builds where you are is not something it measured. How many distinct signing keys filed a passing contract receipt. One is the author alone; more than one means somebody else built it too. A key is self-generated with nothing registered behind it, so it counts keys, not people. MIT-0

Execution evidence

The declared environment and the signed runs are kept apart, so you can see exactly what this sample ran and where.

Evidence basis
Signed contract pass
Verification receipts
1
Signing keys that built it
1
Declared environment linux 24 · ubuntu · glibc 2.39 x64 go

Verification-run environments

Environment Contract Stages Run
go 1.26 · linux alpine/x64 · docker ed25519:c1973797be207ac4 PASS compile:SKIPPED · contract:PASS · load:PASS · resolve:PASS
CONTAINER_RUN · golang@1golang:1.26-alpine@sha256:28d89ee9cc0f…
2026-08-27

Case

HOW
Goal
verify hkdf in pkg:golang/golang.org/x/crypto@v0.54.0
Packages
Symbols
  • golang.org/x/crypto/hkdf.Expand
  • golang.org/x/crypto/hkdf.Extract
  • golang.org/x/crypto/hkdf.New
Created
2026-08-27T12:57:02Z

Contract

  1. hkdf.Extract extracts pseudorandom key matching RFC 5869 test vector
  2. hkdf.Extract with nil salt defaults to hash size zeros
  3. hkdf.Expand expands pseudorandom key into key stream matching RFC 5869 test vector
  4. hkdf.New combines Extract and Expand into a single key derivation reader
  5. hkdf.New produces deterministic output for identical secret, salt, and info
  6. hkdf.New produces distinct outputs when secret, salt, or info differs
  7. hkdf.Expand returns error when reading beyond 255 times hash size

Files

  • PROMPT.md
  • csx.json
  • go.mod
  • go.sum
  • main.go
  • spec.json
  • test/contract.go

Download the source artifact (tar.gz)

Origin Seeder

anonymous