CodeSampleX

Sample

verify pkg:golang/golang.org/x/sync@v0.20.0

sha256:d4eb783da17f1ffe063e406c8fdd697859e6e29af48a086b2601c2cd7816d2fd

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 go

Verification-run environments

Environment Contract Stages Run
go 1.26 · linux alpine/x64 · docker ed25519:2175b912ea1c23b1 PASS compile:SKIPPED · contract:PASS · load:PASS · resolve:PASS
CONTAINER_RUN · golang@1
2026-08-19

Case

HOW
Goal
verify pkg:golang/golang.org/x/sync@v0.20.0
Packages
Created
2026-08-19T18:58:58Z

Contract

  1. errgroup.WithContext cancels derived context and returns error on first subtask failure
  2. errgroup.Group with SetLimit limits maximum concurrent task executions
  3. semaphore.NewWeighted manages weighted access with TryAcquire, Acquire, and Release
  4. singleflight.Group deduplicates concurrent executions for identical keys

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