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Assessment library

Backend & APIs

The skills a Backend & APIs assessment can cover, how the assessment runs, and a sample question to try.

Skills covered

Candidates declare the skills they have, and each sitting is generated for their target role and those skills. These are skills from this field that an assessment can cover.

  • GraphQL
  • Authentication
  • Authorization
  • OAuth 2.0
  • Rate Limiting
  • Caching Strategies
  • Message Queues
  • Webhooks
  • Idempotency
  • Pagination

Sample question

Why should a webhook receiver verify the request signature before it processes the payload?

  1. ATo make the request arrive faster
  2. BTo compress the payload before it is stored
  3. CTo confirm the request came from the expected sender and was not altered in transit
  4. DTo convert the payload into a different format
Show the answer

C. To confirm the request came from the expected sender and was not altered in transit

Anyone who knows the endpoint URL can send it a request. Checking the signature first means forged or tampered payloads are rejected before they can change any data.

A sample only. Real questions are generated fresh for each sitting, so this exact question will not appear.

How assessments are scoredAll assessment fields

What the assessment looks like

A 25-question skills test and a 7-question text interview, about 50 minutes in total.

Sections

  • Multiple-choice questions12 questions
  • Scenario questions8 questions
  • Written case questions5 questions
  • AI text interview questions7 questions
Total time
About 50 minutes
Score validity
Your verified score stays valid for 90 days.
Retakes
One free early retake every 90 days; Premium adds a second.

Look around first. You can browse jobs and save the ones you like before taking the assessment. Saving a job doesn’t require it; applying does.

Browse jobsTry practice questions