This page explains how Kombo works under the hood. If you haven't read it yet, start with What is the Kombo product? first to understand what we do and who we sell to.

The Connection Flow

The connection flow is the only part of Kombo that end-customers interact with directly. It's a white-label component that our customers embed into their product. The end-customer never knows they're interacting with Kombo.

When an end-customer connects their HR/ATS system through the flow, they go through a series of steps: selecting their tool, entering credentials (OAuth or API key or username/password, depending on the tool), and granting access. At the end, we verify the connection works and store the credentials.

The flow is built with a framework we call the Flow Factory. Each integration defines its own flow using a builder pattern. A typical flow has:

• Credential steps where the user enters auth info (subdomain, API key, OAuth, etc.)
• Validation logic that checks the credentials actually work before completing
• Info steps for guiding the user through setup instructions

The whole thing is automatically translated into 5 languages using AI during CI

Syncing (Reading Data)

Once a connection is established, Kombo starts syncing data. We keep a copy of the data in our system so our customers query our API instead of hitting the connected tool directly. This makes things faster, more reliable, and avoids rate limits.

How syncing works:

• We sync data from the connected tool roughly every 3 hours
• The first sync pulls everything. Subsequent syncs are both incremental where the tool supports it, and full to make sure nothing slips through.
• Raw data from the tool's API gets transformed into our unified data model (e.g., ATS Job, ATS Candidate, ATS Application are the same shape regardless of whether the source is Greenhouse, Lever, or SAP SuccessFactors)

The sync function is the core of every connector. It: