API Integration Engineer (HRIS-ATS) - Project Based

We're hiring an API Integration Engineer to own our ATS/HRIS integrations end-to-end: from designing secure REST APIs and webhooks to delivering certified connectors (e.g., Workday, Greenhouse, Lever) and partner enablement assets (Postman collections, docs, sample code). You'll translate client we need an API requests into clear, reliable integrations that recruiters can use without leaving their ATS.

What You'll Do (Key Responsibilities):
- Design and implement Prisma Integration Spec (v1) across environments (sandbox & production).
- Build and maintain REST endpoints (/orders, /packages, /reports, /documents) and webhooks (status, completion, adverse action).
- Implement OAuth2 client-credentials, HMAC-signed webhooks, idempotency keys, and retry logic.
- Ship hosted candidate flows hand-off (invite links) and optional document handoff (pre-signed URLs).
- Deliver results write-back (status + deep link + PDF + JSON summary) into ATS/HRIS...