Use Merge.dev unified ATS API for multi-ATS integration

Steps

1. Register your application in the Merge developer dashboard to receive your API key; include this key as a Bearer token in the Authorization header on all requests to https://api.merge.dev/api/ats/v1
2. Direct each of your customers through Merge Link, the hosted OAuth-style UI component, to connect their specific ATS (Greenhouse, Lever, Workable, SmartRecruiters, etc.); on completion, Merge returns a public_token
3. Exchange the public_token for an account_token by calling GET /account-token/{public_token}; store the account_token per customer and include it as the X-Account-Token header on all customer-scoped requests
4. Use the normalized Merge ATS endpoints to read data across all connected ATSs: GET /candidates returns candidates, GET /applications returns applications, GET /jobs returns jobs — the schema is unified regardless of the underlying ATS
5. Write data back using POST endpoints (e.g., POST /candidates to create a candidate, POST /activities to log a note) where supported by the underlying ATS; Merge's documentation notes which operations are available per integration
6. Monitor webhook events from Merge (configured in the Merge dashboard) to receive real-time notifications when candidate or application data changes in any connected ATS