vcrpy
Automatically mock your HTTP interactions to simplify and speed up testing
Decision gist · record as of 2026-08-14
Yes. VCR.py is actively maintained, has no known vulnerabilities, low install friction, and solves a common testing problem. It's widely used (top 1000 PyPI packages) and the MIT license imposes no restrictions. Install it if your test suite makes HTTP requests and you want faster, more reliable, offline-capable tests.AI-flagged interpretation of the facts on this page — verify before relying
Before you install
- Requires Python 3.10 or later.
- Low install friction with just two runtime dependencies (PyYAML and wrapt).
- Actively maintained with a recent release; last commit on 2026-08-11 and 2982 repository stars indicate solid community backing.
License · maintenance · safety
MIT (permissive) — MIT license (permissive) means you can use, modify, and distribute this package freely in commercial and private projects with minimal restrictions.
last release 2026-07-04 (41 days) · last repo commit 2026-08-11 · 2,982 stars
0 known vulnerabilities (OSV.dev, 2026-08-14) · 27,148,203 downloads/mo, #866 on PyPI
Alternatives
Verify before relying
pip install vcrpy
from vcrpy import VCR
with VCR().use_cassette('cassette.yaml'):
# Your HTTP request code here
pass- Which HTTP libraries are supported for interception (requests, urllib, httpx, etc.).
- Performance overhead of recording and replaying compared to live requests.
- Behavior when cassette files become stale or APIs change unexpectedly.
What it is and what it does
VCR.py is a testing utility that intercepts HTTP requests and records them to disk (as YAML cassettes by default) on first run, then replays those recorded responses on subsequent runs. This eliminates the need for live HTTP calls during testing, making tests faster, deterministic, and runnable offline. It depends on PyYAML for cassette serialization and wrapt for request interception.
The workflow is straightforward: wrap your test code in a context manager or decorator, and on the first execution VCR records all HTTP interactions; on later runs it returns the recorded responses without making real network calls. If an API changes, you simply delete the cassette file and re-run to capture the new interactions.
Use it for
- Speed up test suites that make HTTP calls by replaying recorded responses instead of hitting live servers.
- Run tests offline or in CI environments without external service dependencies.
- Ensure tests are deterministic by always returning the same recorded responses, eliminating flakiness from network variability.
- Test error handling by manually editing cassette files to inject failure scenarios.
- Reduce load on external APIs during development and testing cycles.
Worth the install?
AI-flagged interpretation of the facts on this page. Verify before relying on it.
Yes.
VCR.py is actively maintained, has no known vulnerabilities, low install friction, and solves a common testing problem. It's widely used (top 1000 PyPI packages) and the MIT license imposes no restrictions. Install it if your test suite makes HTTP requests and you want faster, more reliable, offline-capable tests.
Install
vcrpy on PyPI
Before you install
Low install friction with just two runtime dependencies (PyYAML and wrapt). Actively maintained with a recent release; last commit on 2026-08-11 and 2982 repository stars indicate solid community backing.
Requires Python 3.10 or later.
License in practice
MIT license (permissive) means you can use, modify, and distribute this package freely in commercial and private projects with minimal restrictions.
Quickstart
pip install vcrpy
from vcrpy import VCR
with VCR().use_cassette('cassette.yaml'):
# Your HTTP request code here
passVerify before relying
- Which HTTP libraries are supported for interception (requests, urllib, httpx, etc.).
- Performance overhead of recording and replaying compared to live requests.
- Behavior when cassette files become stale or APIs change unexpectedly.
Package facts
| License | MIT permissive |
| Python support | Supports the current Python release >=3.10 |
| Install friction | Low. Pure-Python wheel |
| Runtime dependencies | 2 packagesPyYAMLwrapt |
| Maintenance | Actively maintained 41 days since the last release |
| Last repo commit | |
| First released | |
| Downloads | 27,148,203 / month, #866 on PyPI 30-day window, as of 2026-08-14 |
| Known vulnerabilities | None known OSV.dev, checked 2026-08-14 |
| Classifiers | Development Status :: 5 - Production/StableEnvironment :: ConsoleIntended Audience :: DevelopersLicense :: OSI Approved :: MIT LicenseProgramming Language :: PythonProgramming Language :: Python :: 3Programming Language :: Python :: 3 :: OnlyProgramming Language :: Python :: 3.10Programming Language :: Python :: 3.11Programming Language :: Python :: 3.12Programming Language :: Python :: 3.13Programming Language :: Python :: Implementation :: CPythonProgramming Language :: Python :: Implementation :: PyPyTopic :: Internet :: WWW/HTTPTopic :: Software Development :: Testing |
Evidence: vcrpy-8.3.0-py3-none-any.whl
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See also betamax · pytest-vcr · vcrpy-unittest · keboola.vcr · pytest-recording · placebo · pytest-httpbin · requests-mock · pook · respx