Unified HRIS API

What is a Unified API?

A unified API provides a single, standardized interface to interact with multiple third-party providers. Instead of learning each provider’s unique API format, authentication scheme, and data model, you write code once, and StackOne handles the differences. What StackOne normalizes:

Data models – Consistent field names and structures across providers (e.g., files in Google Drive, SharePoint, and Dropbox all return the same schema; users in Google Workspace, Okta, and 1Password all return the same schema)
Authentication – OAuth, API keys, and tokens are managed per-provider; you just pass an x-account-id header
Pagination – Cursor-based pagination works the same regardless of whether the provider uses offsets, pages, or cursors
Error formats – Standardized error responses with provider-specific details when available

Building AI agents? Use the MCP Server, an AI Toolset SDK, or the Actions API (RPC) instead — same data, optimized for LLM tool calling.

Benefits of the HRIS API

Real-Time Data Synchronization

StackOne’s APIs support real-time data polling, allowing for immediate updates and synchronization across platforms.

Privacy-First Design Ensuring Compliance

With a focus on security, StackOne’s architecture avoids unnecessary data storage, maintaining compliance with data protection regulations.

Synthetic and Native Webhooks for Updates

The platform provides both synthetic and native webhooks, enabling real-time notifications for employee and payroll changes.

Comprehensive HRIS Integration Coverage

StackOne offers pre-built connectors with a wide range of HRIS platforms, simplifying the integration process.

Key Features

The table below shows key features of the HRIS API that make human resources management easier, from real-time employee tracking to payroll management:

Feature	Description
Comprehensive Employee Management	Easily create, update, and retrieve employee profiles, including personal information and employment history.
Payroll and Compensation Management	Manage payroll data, track compensation ranges, and update salary information for employees.
Leave and Attendance Tracking	Monitor and update employee attendance, time-off requests, and manage leave balances.
Real-Time Webhooks	Receive instant notifications for changes in employee profiles, payroll, or leave data.
Document Management	Upload, download, and manage employee documents such as contracts and performance reviews.
Benefits Management	Record and manage employee benefits, including health, retirement, and wellness programs.
Employee Onboarding and Offboarding	Handle employee onboarding, document signing, and offboarding processes, tracking key milestones.

StackOne SDKs & OpenAPI Specification

Use our official SDKs for faster integration. Build with language-native libraries. Full list here.

OpenAPI Specification

Popular SDKs

Node.js Java (JVM) PHP Ruby

Entity Model and Relationships

The following diagram illustrates the key entities within the HRIS API: The following table outlines key entities within the HRIS system and provides a brief description of each.

Entity	Description
Companies	Represents the high-level organizational details of companies present in the underlying system, such as name, display name, and other identifiers.
Employees	Contains comprehensive information about employees, including personal details, contact information, and relationship to other entities.
Employments	Details the employment records of each employee including job positions, start and end dates, compensation details, and more.
Locations	Manages information about the work locations. Location may contain a name associated contact details.
Time Off	Manages records of employee leave requests and their approval status, including request type, duration, and related policies.
Time Off Balances	Tracks the available balance of time off for employees according to specific policies.
Time Off Policies	Defines the policies governing time off requests, including types of leave, duration units, and associated reasons.
Benefits	Manages information about employee benefits programs, providers, and descriptions.
Groups	Organizes employees into logical groupings such as departments, teams, and cost centers.
Jobs	Represents job positions available within the organization, including titles and statuses.
Time Entries	Records employee work time entries, including start and end times, breaks, and status.
Work Eligibility	Tracks employee work authorization documents such as visas, passports, and other legal identification.
Documents	Manages employee-related documentation including personal identification, contracts, and administrative forms.
Skills	Represents employee professional skills, proficiency levels, and related attributes.

Use cases

User Syncing

Ensure your system is up to date with all the employees details in your customers’ HRIS system.

Automated Employee Provisioning

After the recruitment process, automate the provisioning and management of employees in your customer’s HRIS system.

Getting Started

HRIS

ATS

CRM

LMS

Accounting

What is a Unified API?

Benefits of the HRIS API

Key Features

StackOne SDKs & OpenAPI Specification

OpenAPI Specification

Popular SDKs

Entity Model and Relationships

Use cases

User Syncing

Automated Employee Provisioning

​What is a Unified API?

​Benefits of the HRIS API

​Key Features

​StackOne SDKs & OpenAPI Specification

OpenAPI Specification

Popular SDKs

​Entity Model and Relationships

​Use cases

User Syncing

Automated Employee Provisioning

What is a Unified API?

Benefits of the HRIS API

Key Features

StackOne SDKs & OpenAPI Specification

Entity Model and Relationships

Use cases