ETL vs iPaaS vs Unified API: Understanding Levels of Integration Unification

November 17, 2025

'Unification' means different things across integration platforms.

Some tools focus on simplifying setup, while others standardize parts of the data model. Unified.to takes a deeper approach — aligning APIs, schemas, webhooks, and permissions into a single, consistent framework.

Here's what 'unification' really means, and how ETL, iPaaS, and first-generation Unified APIs compare to Unified.to's fully unified architecture.

ETL — None

ETL tools were built to move data between systems, not standardize them.

Every connection uses its own data model, field mapping, and transformation logic — which means no shared schema or consistent API layer.

• Unification level: None
• Data models: Custom per source/destination
• APIs: Not standardized
• Impact: Every new pipeline is a one-off integration

iPaaS — None

iPaaS platforms provide a visual interface and prebuilt connectors, but beneath the surface, each integration is its own workflow.

There's no shared schema, endpoint consistency, or unified way to handle data objects — only custom logic tied to each connector.

• Unification level: None
• Data models: Distinct per vendor
• APIs: Connector-specific; no shared structure
• Impact: Teams rebuild similar logic for every integration

First-Generation Unified APIs — Partial Unification

Unified APIs standardized endpoints across categories like CRM or HR, but most only unified surface-level fields.

Because their data models are shallow, developers still need to map custom fields, handle object variations, and manage edge cases per vendor.

• Unification level: Partial
• Data models: Shallow normalization with gaps
• APIs: Consistent at object level but differ by category
• Impact: Reduces some development time, but not true unification

Unified.to — Complete Unification Across the Stack

Unified.to delivers full-stack unification — not just schemas.

Every API, object, and permission scope follows the same structure across 21 categories, with consistent models for endpoints, data objects, webhooks, and authorization.

• Unification level: Full
• Data models: Deep normalization with shared objects and metadata APIs
• APIs: Consistent endpoints across all categories
• Additional layers: Unified webhooks, OAuth scopes, and permission handling
• Impact: Build once, deploy everywhere — one integration unlocks hundreds

Why Unification Matters

Without deep unification, integrations don't scale.

Each new vendor adds more one-off code, custom mappings, and maintenance overhead. Unified.to eliminates that complexity by creating a single, reusable integration layer.

• Consistent schemas across every system category
• Unified endpoints and permissions across all vendors
• Shared event and webhook architecture
• Full compatibility for AI and real-time workloads

The Bottom Line

Unified.to provides one of the most complete unified architectures available today.

APIs, data models, webhooks, scopes, and auth — all standardized across 350+ integrations so you can launch once and scale everywhere.

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