Moving People Data In and Out of Workday

Every Workday tenant eventually faces the same question: “How do we move people data in and out of Workday without breaking things?” The answer usually involves a mix of EIB, Core Connector: Worker (CCW) and payroll interfaces like PECI and PICOF. Each tool solves different problems: quick one‑off loads, event‑driven deltas, or structured feeds to third‑party payroll. When you understand their patterns, you stop treating integrations as mysterious black boxes and start designing clean, predictable data flows.​​

This playbook explains where each tool fits and how to combine them into practical patterns.

The core tools in your Workday integration toolbox

At a high level, Workday HCM data can move via three main integration approaches for HR and payroll:​​

• Enterprise Interface Builder (EIB)
  • A guided, configuration‑friendly way to build inbound (into Workday) and outbound (from Workday) integrations.
  • Supports formats like CSV and XML, and can be scheduled or launched manually.​​
• Core Connector: Worker (CCW)
  • A pre‑configured Connector that detects worker‑related changes and outputs “delta” data based on events or schedules.
  • Ideal for ongoing, event‑driven integrations with downstream systems that need near real‑time updates.​
• Payroll Interface templates – PECI and PICOF
  • PECI (Payroll Effective Change Interface): sends all effective‑dated changes for workers in a pay period to a payroll provider.​
  • PICOF (Payroll Interface Common Output File): sends a “top‑of‑stack” snapshot of current values for each worker.​

Think of EIB as your Swiss Army knife, CCW as your event‑driven delivery truck, and PECI/PICOF as specialized payroll trucks with strict manifests.

When to use EIB

EIB shines when you need simple, structured data movement and can tolerate batch runs.​​

Common use cases:

• Data loads into Workday
  • Mass updates for workers, positions, organizations or compensation using inbound EIBs.
  • Initial data migration for go‑live or new modules.​
• Outbound data extracts
  • HR data exports to analytics tools, data warehouses, or vendor systems that can consume CSV/XML on a schedule.
  • Audit or snapshot files for regulatory or internal control purposes.​

Patterns:

• Use EIB when:
  • The integration is periodic (daily, weekly, monthly).
  • Change detection can be handled using effective dates or report filters instead of continuous event logic.
  • The consumer system is comfortable with full or filtered extracts.​​

EIB is often 20–30% of a mature tenant’s integrations: quick to build, transparent to support, and flexible enough for many HR use cases.​​

When to use Core Connector: Worker (CCW)

Core Connector: Worker is built for ongoing worker data feeds to downstream systems like LMS, IAM, security badges, or benefits platforms.​

Key characteristics:

• Event‑driven deltas
  • CCW can be triggered by worker events (hire, terminate, job change, compensation change) or run on a schedule.
  • Outputs only the records that changed, not the whole population, improving performance and efficiency.​
• Configurable output
  • You choose which worker attributes to include, and can leverage Calculated Fields to derive additional outputs such as full names, tenure, or custom flags.​
• Flexible formats
  • Supports XML, JSON, CSV and transformations via XSLT.​

Patterns:

• Use CCW when:
  • A downstream system needs near real‑time or frequent worker updates.
  • You want delta‑only outputs instead of full extracts.
  • You can define a stable integration contract (fields, formats, triggers).​​

Examples: outbound feeds to identity providers, benefits vendors, or internal HR data hubs that must stay synchronized with Workday.

PECI vs PICOF: which payroll interface to pick?

For payroll, PECI and PICOF are the main templates that Workday customers use with third‑party payroll engines.​

• PICOF – Payroll Interface Common Output File
  • Sends one consolidated snapshot of current values for each worker in scope.
  • “Top‑of‑stack” logic: only the latest value per field per worker is sent.​
  • Simpler to consume but does not show the full sequence of changes in a period.
• PECI – Payroll Effective Change Interface
  • Sends a sequence of effective‑dated changes for each worker across the pay period.
  • Captures hires, terminations, salary changes, and other updates as separate transactions, with timestamps.​
  • Provides higher data integrity, better auditability and automated corrections.

Real‑world pattern:

• PICOF behaves like “send me where the worker ended up this period”.
• PECI behaves like “send me every change the worker went through this period”.​​

Many organizations are moving from PICOF to PECI to improve automation, compliance, and reduce manual corrections.​

Choosing the right pattern

From a practitioner angle, choose your integration pattern based on:

• Frequency and volume
  • Low frequency, flexible volume → EIB.
  • High frequency, event‑driven → Core Connector: Worker.
  • Pay‑cycle driven with detailed change history → PECI.
  • Pay‑cycle driven where snapshot is enough → PICOF.​​
• Data semantics
  • Do consumers need just current values, or the full change history?
  • Are they using the feed to run transactions (payroll) or to maintain a reference copy (LMS, IAM)?​
• Error handling and audit
  • PECI offers richer visibility into transaction sequences across pay periods.
  • PICOF is simpler but relies more on external system logic for audit.​

Mapping this out in an “integration architecture” diagram helps explain choices to HR, payroll and IT stakeholders.

Practical patterns you can reuse

Some common patterns for moving people data:

1. HR data to analytics / data warehouse
   • Use Outbound EIB or report‑based integrations to push worker, org and comp data nightly.
   • Support ad‑hoc extracts via secured custom reports.​
2. Worker data to downstream HR systems
   • Configure Core Connector: Worker with event triggers for hires, job changes, terminations.
   • Use Calculated Fields and XSLT to shape outputs for each consumer.​​
3. Global payroll integration
   • Use PECI to send effective‑dated worker changes per pay group and pay period.
   • Pair with inbound files that load pay results or statuses back into Workday for reporting.​
4. Bulk corrections or backloads
   • Use Inbound EIB for one‑time or periodic corrections (for example, mass cost center changes, job code realignments).
   • For payroll, use PECI’s corrections capabilities where supported to avoid one‑off manual fixes.​

These patterns keep integrations consistent and easier to support over time.

Governance, monitoring and “integration hygiene”

Integrations are not “set and forget”. Good tenants treat them like critical infrastructure.

Key practices:

• Inventory and ownership
  • Maintain an inventory listing each EIB, CCW, PECI/PICOF integration, its purpose, schedule, and owner.​​
• Monitoring and alerts
  • Use Workday’s integration monitoring to track statuses, errors and runtimes.
  • Set up alerts so failures for payroll‑critical interfaces (PECI/PICOF, CCW to IAM) are acted on immediately.​​
• Change control
  • Version and test changes to Calculated Fields, field mappings, or triggers carefully; a small change can break downstream files.
  • Coordinate with vendors when altering PECI/PICOF layouts or logic.​
• Security
  • Restrict who can view payloads that contain sensitive PII and comp data.
  • Ensure SFTP/API endpoints use secure protocols and proper key rotation.​

With clear patterns, strong governance and the right tool for each job, moving people data in and out of Workday stops being a risky art and becomes a repeatable discipline. EIB, Core Connector: Worker, PECI and PICOF then work together as part of a coherent integration architecture rather than isolated projects.