Using Dynamic Variables and Sequential Request Runners for API Testing
Boost your API debugging speed using {{variable}} placeholders across environments and running automated sequential stress loops directly inside your browser.
Why Dynamic Variables Matter in API Workflows
Hardcoding base URLs (such as https://staging.example.com/api/v1) and authentication tokens across dozens of test requests leads to repetitive editing whenever credentials rotate or environments change. Dynamic variables solve this by letting you define values once and reference them anywhere using {{variableName}} syntax.
How to Use Dynamic Variables in Apier
Apier supports variable interpolation everywhere inside the request builder:
- URL:
{{baseUrl}}/users/{{userId}} - Headers:
Bearer {{authToken}} - Query Parameters:
page={{currentPage}} - Body:
{"email": "{{userEmail}}"}
Typing {{ brings up an autocomplete suggestions popover, allowing rapid selection without leaving your keyboard.
Automating Repetitive Tests with the Sequential Auto-Runner
Validating rate limits, stress-testing endpoint responsiveness, or verifying batch operations often requires triggering an endpoint multiple times. Apier features a built-in Sequential Runner:
- Configure your target request in the workspace.
- Open the Auto Runner panel.
- Set your desired execution count (between 1 and 50 iterations).
- Define the delay interval between requests (from 200ms up to 10,000ms).
- Start the runner and monitor the real-time progress bar, success metrics, and individual iteration latencies.
All test runs are tracked in your local history so you can review individual response timestamps and latencies whenever needed.