A local workspace for dependency debugging

Your dependencies.
Your rules.

Debug the services your application depends on, without changing your code.

Proxy real APIs and databases. Simulate the services you don’t have. Pause requests, inject failures, and see exactly what happened. All on your own machine.

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checkout-serviceLocal session
Dependency timeline
Your appUnchanged code
FlowReactorInspect & control
DependencySimulate or proxy
TRY A BEHAVIOR
OPERATIONRESULTDURATION
GET /api/orders
200 OK812 ms
SELECT inventory
OK8 ms
800 ms latency applied
Interactive illustration · behavior at the dependency boundary

BUILT AROUND REAL PROTOCOLS

HTTPPostgreSQLMySQLDynamoDBCognito
Supported behavior varies by service. FlowReactor focuses on practical development workflows.
AT THE DEPENDENCY BOUNDARY

Turn “what if”
into something you can see.

Your application is a black box.
The dependencies it talks to don’t have to be.

Simulate

Build a local dependency you control. Shape HTTP responses, DynamoDB data, and supported Cognito behavior.

A predictable starting point

Proxy

Keep a real database behind the connection. Put FlowReactor between your client and PostgreSQL or MySQL.

Real services. More control.

Fault

Explore slow responses, timeouts, and broken connections. See what your application does when dependencies stop behaving.

Make failure intentional

Observe

Follow dependency activity in one timeline. Inspect operations, payloads, duration, and outcomes in context.

See what actually happened

Debug

Pause supported dependency operations. Inspect the request, then choose when and how it continues.

Work at your own pace

Control

Tune behavior at the dependency boundary while your application keeps using its normal drivers and SDKs.

No application instrumentation
A DIFFERENT WAY TO DEBUG

Change the destination.
Keep your application.

Use normal clients and SDKs.
Control the other side of the connection.

01

Set up a dependency

Create a simulator or configure a proxy to your existing service.

02

Point your application at it

Update the dependency’s address or connection string in your development configuration.

03

Explore the behavior

Inspect traffic, apply faults, and pause supported operations while your application runs.

No assumption about your framework, language, or application’s entry point. Just the dependencies you choose to route through FlowReactor.

MAKE THE NEXT FAILURE REPRODUCIBLE

Meet your new
dependency workspace.

Find the latest available Windows and Linux releases.

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