Oracle is one of the top names in IT. Their HCM is popular among enterprises with more than 1,000 employees and boasted for its implementation and CS practices.
Oracle's HCM suite is built for the cloud and made for connecting every single HR process. It's good for teams looking to have a single source of truth for HR data in order to improve decision making. Their product includes talent management, recruiting, workforce management, payroll, and HCM analytics. The interface is not the best-looking out there and UX can be frustrating for employees and HR alike, but they're still one of the top choices for large scale implementations.
Oracle HCM has a REST API with detailed documentation.
Oracle doesn't provide pricing details for their HCM upfront. To get a quote, you'd have to request a demo, but they also offer interactive product tours that you can take before chatting to a sales rep.
Oracle has several implementation plans and checklists in place depending on what kind of modules you're looking to bring in and which areas will be impacted. Whether it's strategic workforce planning, general HR, compensation, benefits, or global payroll, they've got an implementation process to guide you through getting set up.
Naturally for a company their size, Oracle offers advanced support services for general installation and services that are product-specific. These include expert support, systems optimization, managed applications, a help desk, security, and more.