HubSpot Operations Hub is HubSpot's iPaaS / data-ops product. It handles data sync to external systems (Salesforce, NetSuite, BigQuery, Snowflake), programmable workflow automation, custom code actions in JavaScript, and data quality jobs (deduplication, formatting, enrichment).
For mid-market customers running HubSpot as their primary CRM, Operations Hub is what makes HubSpot the centre of the operational data graph rather than a silo. The two-way data sync to Salesforce / NetSuite is the most common deployment; programmable workflows for revenue-ops automation (route the lead based on territory + ARR + product fit) is the second.
The discipline that prevents Operations Hub from becoming a tangled mess: name + tag every workflow + sync job with an owner, document the trigger + the outcome, maintain a documented test sandbox, run a quarterly cleanup of disabled-but-undeleted jobs.