SmartRecruiters Applicant Tracking System API Integration

---

An Illinois-based background check company wanted their recruiters' clients to initiate background checks directly from within SmartRecruiters, the applicant tracking system (ATS) those clients were already using. Rather than requiring recruiters to context-switch between two platforms, the client wanted a seamless, embedded experience. We delivered that by building a middleware layer that implemented SmartRecruiters' Assessment API (2021) specification.

The client's background check platform was a standalone system with its own ordering workflow. Their customers had to manually copy candidate information from SmartRecruiters into the background check portal to initiate a check — time-consuming, error-prone, and creating friction at a critical stage of the hiring process.

The client needed a solution that would:

• Surface their background check packages inside SmartRecruiters so recruiters could order them without leaving the ATS
• Pass candidate and job data from SmartRecruiters directly into the ordering workflow
• Return background check results back into SmartRecruiters so recruiters could view status and outcomes from one place
• Work reliably at scale for multiple client organizations simultaneously

SmartRecruiters offers a well-defined partner integration framework through its Assessment API (2021): the platform's current and actively maintained standard for third-party assessment integrations as of 2025, replacing an older Marketplace-era API. This specification defines a two-way contract: SmartRecruiters calls endpoints on the partner's side to retrieve available packages and place orders, while the partner calls SmartRecruiters endpoints to report configuration, credentials, and results.

We served as the engineering team responsible for designing and building the middleware that fulfilled the partner side of this contract. The middleware acted as the bridge between SmartRecruiters and the client's existing background check platform.

The Assessment API required us to implement three core partner-side endpoints. The /integration endpoint receives customer-level credentials from SmartRecruiters, allowing the middleware to associate a given SmartRecruiters account with the correct customer account in the background check system. The /packages endpoint returns a catalog of available background check packages so recruiters can select the appropriate screening product directly from the SmartRecruiters UI. The /packages/orders endpoint accepts order requests from SmartRecruiters containing candidate information, job context, and the selected package, then translates and forwards that order to the background check platform. On the outbound side, the middleware called SmartRecruiters endpoints to push results back once a background check was complete, including support for attaching report documents directly to the candidate record.

The solution was built using a modern, cloud-ready stack suited to the reliability and scalability demands of a multi-tenant integration. We used .NET for the back-end API layer, implementing the partner endpoint specification and handling all business logic for translating between SmartRecruiters' data model and the client's internal system. SQL Server served as the relational database, storing order state, tenant configuration, and credential mappings needed to route requests to the correct customer account. The service was hosted on AWS Elastic Beanstalk, which provided a managed environment that simplified deployment and allowed the service to scale with demand.

The multi-tenant architecture was an important design consideration. Because the middleware served multiple SmartRecruiters customer accounts simultaneously, the integration layer had to securely isolate configuration and credentials on a per-tenant basis while sharing the same underlying infrastructure.