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API Testing · /// OpenAPI Load Testing

Drop in an OpenAPI spec. Get a load test.

The visual flow editor imports OpenAPI / Swagger specs and scaffolds operations automatically. Author the user journey across imported endpoints visually, then replay as a load test AND as a continuous synthetic check. No script project, no hand-authored test library.

OpenAPI / Swagger import21 executable API flow nodesLoad + monitoring on one engine

API sources. OpenAPI spec imported, endpoints scaffolded.

The Problem

OpenAPI specs are documentation. Not tests.

Most teams ship OpenAPI / Swagger specs as living documentation, then maintain a separate test library by hand. The spec drifts. The test library drifts. The gap shows up in production.

Hand-authored tests drift from spec.

A new endpoint added to the spec doesn’t automatically get a test. Test coverage decays with every release until someone audits it manually.

Two systems, two sources of truth.

OpenAPI spec in one repo, Postman collection or VuGen scripts in another. The spec changes; nothing else updates automatically.

Load testing the spec is awkward.

Generic load tools don’t consume OpenAPI directly. They need scripts hand-authored from the spec, which adds yet another translation step.

Why OpenAPI-driven API testing

Spec, scaffold, flow, load and monitoring.

Import the OpenAPI spec. The flow editor scaffolds operations automatically. Each operation becomes a node template. Author the user journey across imported endpoints, then replay across modes. The spec stays the source of truth.

OpenAPI / Swagger import

Drop in the OpenAPI / Swagger spec. Operations scaffold automatically. Endpoint changes re-import, so test coverage tracks spec evolution.

Visual journey authoring

Drag-drop the imported operations into a user journey. 21 executable nodes across a 28-node palette compose end-to-end flows: flow control, request, data, control, assertion, Scriban-based built-in transformation.

Load and monitoring replay

The flow authored once replays as a load test AND as a continuous synthetic check. One asset, two operational modes.

Spec to scaffold

OpenAPI imported, operations scaffolded.

Drop the OpenAPI / Swagger file into the API Sources view. Each operation becomes a node template ready to drop into a flow. Spec changes re-import, and test coverage tracks the spec.

  • OpenAPI 3.x and Swagger 2.x both supported.
  • Endpoint metadata, parameter schemas, response shapes imported automatically.
  • Re-import detects new operations, so coverage tracks spec evolution.
  • Built-in transformation (Scriban) is available for cases the spec doesn’t cover.

API sources. OpenAPI spec imported, operations scaffolded.

Author the journey

Drag, drop, connect, replay.

Compose the user journey visually across imported operations. 21 executable nodes handle flow control, request shaping, data, control, and assertions. The same flow runs as load and monitoring without re-authoring.

  • Flow control: flow.start, flow.end, flow.call.
  • Request: request.operation (OpenAPI-driven), request.raw, request.replay.
  • Assertion: assert.status, assert.jsonpath, assert.schema, assert.latency, assert.contract.
  • Replayable as load test AND as continuous synthetic check.

Flow canvas with a multi-node API journey.

Proof

Numbers from the platform.

1,000+

API endpoints

powering every module

1.45M+

Tests run

across the customer base

8

Products, one platform

testing + monitoring + analytics + service levels

From €1,099

Per week · transparent

starts at 50 vUsers

Import your OpenAPI spec on a call.

Bring the spec. We’ll import it in the visual editor, scaffold the operations, author a multi-step user journey, and run it as a load test live.

Questions

Frequently asked.

Does the import support OpenAPI 3.x and Swagger 2.x?

Yes. Both versions are supported. Endpoint metadata, parameter schemas, and response shapes are imported automatically. Re-import detects added or modified operations.

Can the imported flow run as both load and monitoring?

Yes. The flow authored from the imported spec replays as a load test (50–25,000 vUsers as a licence tier) AND as a continuous synthetic monitoring check on a configurable schedule. One asset, two modes.

What happens when the OpenAPI spec changes?

Re-import the spec. The flow editor detects added or modified operations. Existing flows continue to work; new operations become available as draggable nodes for additional journeys.

Can I add custom logic that isn’t in the spec?

Yes. The 28-node palette includes 21 executable nodes covering flow control, request, data, control, assertion, and a Scriban-based built-in transformation node for cases the spec doesn’t cover.

How does pipeline integration work?

LoadGen exposes 1,000+ REST endpoints. CI/CD pipelines can trigger runs and gate deploys on assertion failure, latency regression, or error-rate threshold breach. Analytics + AI flags regressions per release.

What does OpenAPI API testing cost?

API Testing pricing is provided on request. Load Testing is €1,099 per week at the 50-vUser tier, and End-to-End Monitoring is €899 per Agent per month. Multi-module bundles are quoted on a call.

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