Sample
Inject context variables into structlog loggers with merge_contextvars, scoped lifecycles, and asynchronous task isolation
sha256:6dec637d6343afe74048a5fc63a4dfef59e139a0fac7ba3e70880f3c05d653fa
PUBLISHED
L3_CONTRACT_PASS
MIT-0
Execution evidence
Declared environment and signed verification runs are separated so you can see exactly what this sample proves.
Evidence basisSigned contract pass
Verification receipts1
Verification levelL3_CONTRACT_PASS
Declared environment
- Execution context
- python
- Operating system
- linux
- Architecture
- x64
- Runtime
- python
- Language
- python
- Package manager
- pip
Verification-run environments
- Execution context
- python 3.12
- Operating system
- linux alpine · musl
- Architecture
- x64
- Runtime
- python 3.12
- Language
- python
- Package manager
- pip
- Execution
- container · docker
CONTAINER_RUN · compile:SKIPPED · contract:PASS · load:PASS · resolve:PASS · python@1 · 2026-08-17
Case
- Goal
- Inject context variables into structlog loggers with merge_contextvars, scoped lifecycles, and asynchronous task isolation HOW
- Packages
-
structlog 26.1.0
- Environment
- python
- Created
- 2026-08-17T19:44:47Z
Commonly assumed
Calling bind_contextvars automatically propagates context variables to all structlog loggers without requiring merge_contextvars in the processor chain.
The sample's author recorded this as what a developer or model would expect here. The contract below is what actually ran.
Contract
- Calling bind_contextvars has no effect on log output unless merge_contextvars is explicitly present in the processor chain, and bound logger fields override conflicting context variables.
- bound_contextvars restores previous context values upon block exit or exception while preserving unrelated keys.
- reset_contextvars with tokens returned by bind_contextvars restores previous variable bindings.
- unbind_contextvars deletes specified keys and clear_contextvars removes all context variables.
- get_merged_contextvars returns current contextvars merged with bound logger context without mutating either.
- Concurrent asyncio tasks inherit parent contextvars but mutate their context in complete isolation without leaking to siblings or the parent.
Files
- NOTES.md
- csx.json
- pyproject.toml
- requirements.lock
- requirements.txt
- test/contract.py
Download the source artifact (tar.gz)
Origin Seeder
csx-seed
Verification receipts
- python 3.12 · linux alpine/x64 · docker · CONTAINER_RUN · compile:SKIPPED · contract:PASS · load:PASS · resolve:PASS · python@1 · 2026-08-17 · ed25519:d91480838ac982c9