An HRIS is the system of record for people, which means its job is to be authoritative rather than comprehensive. Payroll, recruitment, learning and access management all need to know who works here, and the value of the HRIS is that they can all ask one place and get the same answer.
Decide what the HRIS owns
Identity, contract, reporting line, location and start date at minimum. Everything else can live elsewhere and reference it. Organisations that let payroll or a directory own the employee identity end up with two versions of a person and a reconciliation somebody performs forever, and the reconciliation never gets removed once it exists.
Integrations are a maintained thing
A connector is not a checkbox on a vendor page; it is software that has to keep working as both products change. Ask who maintains it, how changes are communicated, and what happens when a field is added. Budget it as ongoing work with an owner rather than as a one off configuration task.
Test the leaver, not the joiner
Joiners are easy because everybody designs for them. A leaver has to reach payroll for a final run, reach access management to have accounts removed, and remain in the record for retention purposes. That combination breaks thin integrations and exposes exactly where the product's model is weak.
Questions people ask about saas hris software
What is the difference between HRIS and HR software?
In practice very little, and HRIS emphasises the system of record function. What matters is whether it is authoritative for identity.
How many integrations is too many?
As many as have an owner. An unowned integration fails quietly and is discovered when somebody who left still has access.
Should the HRIS or payroll own the person?
Usually the HRIS, because it captures changes first. What matters is that it is decided and enforced.