Environments
The Flex Forward API provides two environments for production operations and development testing.Available environments
| Environment | Base URL | Courier connection |
|---|---|---|
| Production | https://api.flexforward.com | Live courier services |
| Development | https://sandbox.flexforward.com | Courier sandbox services |
Development environment
The development environment connects to courier sandbox services (e.g., YunExpress sandbox). Use it for:- Testing your integration without creating live shipments
- Validating request formats and response handling
- Developing error handling and retry logic
Sandbox courier services may return simulated tracking data and label documents. Behavior may differ from production in response timing and available tracking statuses.
Sandbox test data
The development environment supports test values that produce predictable tracking responses. Use these to verify your integration handles different shipment outcomes:| Ship-to postal code | Simulated tracking result |
|---|---|
90001 | Delivered — shipment completes normally |
90002 | Exception — delivery exception occurs |
90003 | InTransit — shipment stays in transit indefinitely |
90004 | Cancelled — shipment is cancelled |
Test values and simulated responses are subject to change. Contact the Flex Forward team for the latest sandbox test data.
Credential separation
Use separate API tokens for each environment. Do not use production credentials in development or vice versa.Token best practices
- Store tokens in environment variables or a secrets manager
- Never hard-code tokens in source code or commit them to version control
- Use separate tokens per environment to prevent accidental production requests during development
- Rotate tokens regularly
Rate limits
Rate limits are not currently enforced. As a guideline, keep request volume below 10 requests per second per account. Rate limit headers (X-RateLimit-Limit, X-RateLimit-Remaining, X-RateLimit-Reset) are not currently included in responses.
If rate limiting is introduced in the future, it will be communicated through the Changelog with advance notice. Contact the Flex Forward team at [email protected] to discuss capacity planning for high-throughput integrations.
Go-live checklist
Before switching from development to production:- Development token issued and tested
- Production token approved by the Flex Forward team
- Shipper account configured for production courier(s)
- Label creation tested successfully in development
- Label document retrieval tested
- Tracking retrieval tested
- Idempotency behavior verified (duplicate key returns same result)
- Error handling implemented for all status codes
- Required courier and shipping lane setup confirmed