What Postman Can’t Test, Keploy Cancatch what breaks
Auto-Generated Tests from Traffic vs Manual API Collections
Keploy auto-generates API tests by capturing real production traffic using eBPF, requiring zero code changes. Postman is a collaborative API platform where teams manually build and organize request collections, write test scripts, and share workspaces. Keploy suits teams wanting instant regression coverage; Postman suits teams needing a visual API design and collaboration hub.
eBPF · zero code changesHow Keploy turns real traffic into a test suite
One pipeline, running the moment your app receives a request. No SDKs, no sidecars, no test scripts — just kernel-level capture that becomes deterministic regression coverage.
- 01Real API trafficLive requests + responses from your running app
- 02eBPF captureKernel-level recording — zero code changes
- 03NormalizeTime-freeze + field noise removed automatically
- 04Generate testsDeterministic test cases from actual behavior
- 05Generate mocksEvery downstream dependency stubbed for you
- 06Replay in CIRuns locally, in CI, or in-cluster on Kubernetes
- 07Regression detectionDiffs flagged before they reach production
See how the capture-replay engine works under the hood.
Trusted by engineering teams at scale
Why teams switch from Postman
Keploy eliminates manual test authoring by generating tests automatically from real traffic — no scripts, no stubs, no infrastructure setup.
Want to generate regression tests from production traffic without writing code
Need automatic mock generation for databases and external services
Your team ships fast and cannot afford time to manually maintain test collections
The numbers behind the switch
Industry data on how much manual testing costs teams — and what Keploy delivers from the first recording session.
Writing tests, configuring mocks, debugging flakiness — not building features that ship.
A routine rename or interface change silently invalidates more than half your suite.
Keploy generates tests from every request your API actually handles — no guessing.
Traffic capture reaches edge cases, error paths, and concurrent requests no dev would write.
Pain stats sourced from developer productivity surveys. Coverage stats from Keploy production recording sessions across 50+ engineering teams.
Every number here comes from teams running Keploy in CI.
Zero code. Real tests. Automatically.
Keploy's eBPF agent intercepts every API call at the kernel level and turns live traffic into test cases with dependency mocks — no SDK, no sidecars, no annotations.
Incoming API Requests
Keploy Agentrecording · analyzing · generatingEvery API call your app makes gets captured, replayed as a test, and its dependencies auto-mocked — continuously, from real traffic.
How they compare, dimension by dimension
A logical breakdown across the dimensions that matter. Click any row for real-world KPI impact across industries.
Auto-generates from captured production traffic via eBPF
Manual request collections with JavaScript test scripts
Zero code changes needed to instrument or capture
No code changes but requires manual test script authoring
Auto-generates mocks for all downstream dependencies
Manual mock servers via Postman Mock Server feature
Built-in time-freezing and field normalization
Requires custom JavaScript logic in pre/post-request scripts
Native CLI integration with any CI pipeline
Newman CLI or Postman CLI for collection runs in CI
Language-agnostic — captures at network level
Language-agnostic — works with any API over HTTP
KeployClick any dimension to see real-world KPI impact across industries.
Dive into how each capability actually works.
Your tests miss more than you think
Manual tests cover paths developers remember to write — usually just the happy path. Keploy captures every pattern production traffic actually generates.
Coverage grid shows 8 common endpoints × 10 production scenario types. Manual tests cover only what developers remember to write. Keploy captures every pattern your API actually serves in production.
Keploy is open source — read the code that captures this coverage.
The infrastructure you're maintaining
Traditional testing stacks require a shadow infrastructure to exist alongside your real app. Keploy eliminates all of it — tests and mocks come from actual traffic, not from services you run and maintain.
How they work differently
Architectural differences that affect workflow, cost, and velocity.
KeployeBPF-basedKeploy uses eBPF to record real API calls and responses from your running application, then replays them as regression tests. It auto-generates mocks for downstream dependencies and handles non-deterministic fields like timestamps through time-freezing. No test scripts to write — you get coverage from actual production behavior.
Postman provides a GUI workspace where developers manually create API request collections, write JavaScript test scripts, and organize them into folders. Teams share collections through Postman workspaces, run them via Newman CLI in CI, and use Postman Monitors for scheduled checks. It doubles as an API design and documentation tool.
When to use each tool
Specific scenarios where each tool delivers the most value.
Keploy is the better fit when…
- Want to generate regression tests from production traffic without writing code
- Need automatic mock generation for databases and external services
- Your team ships fast and cannot afford time to manually maintain test collections
- You need to handle non-deterministic data like timestamps and UUIDs automatically
- Prefer an open-source, self-hosted solution with no per-seat licensing
Postman is the better fit when…
- Need a visual API design and collaboration platform for your team
- Want to manually craft and curate specific test scenarios with custom assertions
- Your workflow relies on shared workspaces and Postman's ecosystem of public APIs
- Need built-in API documentation generation and publishing
- Team is already deeply invested in Postman collections and Newman CI pipelines
Compare the full workflow for your own stack.
The workflow you're escaping
Same starting point, same finish line. One path is short because Keploy does the tedious middle for you — the other is where teams lose days every sprint.
Without Keploy (Postman / manual)
Every dependency is your problem, and every code change ripples back through the test suite you hand-built.
With Keploy
Record once from real traffic, replay anywhere. Tests and mocks are generated and stay in sync automatically.
Cut the maintenance middle out of your test suite.
The test maintenance trap
With Postman, every feature commit generates a hidden tax — a follow-up "fix tests" commit. The commit history tells the whole story.
Deterministic replays, no flaky tests — see how.
Switch from Postman in minutes
Choose the path that fits your workflow. Both are up and running the same day.
Install, record real API traffic, then replay it as regression tests — zero code changes, zero framework dependencies.
# 1. Installcurl --silent -O https://keploy.io/install.sh && source install.sh# 2. Record your traffickeploy record -c "your-start-command"# 3. Replay as testskeploy test -c "your-start-command" --delay 10Paste your cURLs, drop in an OpenAPI spec or Postman collection, and click Generate. Keploy builds your test suite in seconds.
Real-world scenarios
How Keploy handles the challenges your team actually faces.
Your team ships 50 PRs/week and needs regression coverage
Keploy captures production traffic once and generates a regression suite automatically. Every PR runs these tests in CI without anyone writing or maintaining test scripts. Coverage grows as traffic patterns evolve.
Postman requires engineers to manually create and update collections for new endpoints. At 50 PRs/week, keeping collections current becomes a bottleneck unless a dedicated QA team maintains them.
You're migrating from monolith to microservices
Keploy records traffic at the monolith boundary, auto-generates mocks for downstream services, and replays tests against new microservices to verify behavioral parity. No manual mapping needed.
Postman collections can test individual microservice APIs, but you need to manually create mock servers for dependencies and write comparison tests to verify the migration did not change behavior.
Join the teams shipping with confidence on Keploy.
What you write vs what Keploy writes
The same test coverage — one approach takes hours of setup and ongoing maintenance, the other takes five minutes and zero boilerplate.
Every new endpoint needs a new file. Every refactor breaks tests. Every non-deterministic value (timestamps, IDs) needs custom handling.
Keploy captures the real request, response, and all dependency calls. Non-deterministic fields are auto-detected and excluded from assertions.
Frequently asked questions
Common questions about choosing between Keploy and Postman.
Still have questions? The docs and community can help.
Looking for a Postman alternative?
Engineering teams evaluating Postman alternatives often compare it with Keploy for API testing and regression coverage. Keploy captures real production traffic via eBPF and auto-generates tests with dependency mocks — requiring zero code changes. The key differences come down to how tests are generated (traffic-based vs manual), how dependencies are mocked (automatic vs configured), and what infrastructure changes are needed (none vs SDK/sidecar/containers).
Ready to stop writing tests manually?
Keploy captures your real API traffic and turns it into a regression suite automatically. Zero code changes. Full coverage from day one.