Merge vs. Unified.to: which Unified API is right for your product?
April 9, 2025
If you're searching for the best unified API solution or Merge alternative, you're already asking the right questions. The integration layer you choose defines how fast you ship, how deeply your product integrates across different use cases, the types of customers you can support, and how ready you are for AI.
Merge helped standardize integrations for HR and ATS tools. But if you're building real-time workflows, AI-native apps, or anything beyond HR, you'll hit limits fast.
Unified.to is what comes next—a unified API that's real-time by default, built for AI-first products, and designed for teams that want full control of their data.
Real-time by default
Most unified APIs—including Merge—are designed for polling and scheduled syncs. That works if you're moving data into a warehouse or systems that don't require instant updates. But it breaks when your customer-facing product depends on live context.
Unified.to is built for real-time delivery from the ground up.
- Native Webhooks where available
- Quick frequency Virtual Webhooks for the 89% of APIs that don't support them
- No polling logic or manual sync schedules required
Whether you're building AI assistants, live dashboards, or just want to avoid the cost and complexity of polling data, Unified.to gives you real-time updates out of the box.
Actually unified, not just abstracted
Merge abstracts APIs. Unified.to unifies them.
Merge gives you a common surface area—but not a consistent data model. You'll still deal with inconsistent, custom fields, and edge-case handling per integration.
Unified.to goes further with deep normalization across 19+ categories, including:
- Consistent deep schemas and enum values that support a wide range of use cases
- Cleanly mapped associations
- Unified pagination and error handling
This is what makes it easier to build once, scale across platforms, and keep downstream logic simple—especially when powering AI features or multi-source workflows.
AI-ready, not AI-adjacent
Merge gives you API access. Unified.to gives you normalized, real-time, AI-ready infrastructure. One helps you fetch data. The other helps you build intelligent products.
If you're building retrieval-augmented generation (RAG), AI agents, product copilots, or workflow automation based on customer context, your integration layer needs access to real-time data.
With Unified.to, you can:
- Access live, clean, and normalized data from CRMs, HR platforms, file storage, support systems, and more (view 250+ live integrations)
- Feed unified data directly into your databases via Database Sync (Supports Postgres, MySQL, MongoDB, MSSQL, CockroachDB, and MariaDB) or our Unified Webhooks
- Combine event-driven updates with historical data in your own architecture
This is how teams move from AI experiments to production-grade capabilities.
Built for trust: zero-data architecture and flexible data access
Unified.to doesn't store or cache your customers' third-party data. This zero-data architecture reduces your compliance footprint while giving you more control over how data flows into your systems.
Merge, by contrast, stores your customers' data—including authorization data—by default. That might make retrieval simple in the short term, but it introduces a significant security liability. You're responsible for data you don't control, stored in a vendor's infrastructure you don't own.
And it's not just a security concern—it's long-term lock-in. Migrating off Merge means untangling not only your integration logic, but your customers' inaccessible stored data and credentials. That's a costly, challenging move if your roadmap changes.
With Unified.to, you get multiple ways to access customer data—on your terms:
- Unified API – Query any supported integration with a consistent, normalized schema
- Virtual + Native Webhooks – Get webhook-style updates, even from providers that don't support them natively
- Database Sync – Push clean, structured records into your own database for analytics, AI workflows, or embedded dashboards
All three options run on the same unified models—so switching between them doesn't require rewriting your integration layer.
Developer-first experience
Comprehensive docs and 7 auto-generated, version-aware SDKs get you started. Hands-on support for every plan including our trial gets you through production.
Unified.to maintains a 5-star G2 rating and has earned a reputation for fast, collaborative support, with product teams often citing responsiveness and flexibility as key to their launch speed.
"Unified.to's integration depth and breadth give us the flexibility to experiment and innovate." — Steve Hockey, CEO, MyHub (read case study)
"Unified is impressively fast at responding to our integration requests and adding them within days."
— Kevin Kliman, CEO, Humi (read case study)
"The clear and open Unified data models were spot-on. Having a system that's opinionated but flexible, that you can map your schema against, makes the integration process so much smoother."
— Bijan Vaez, CEO, Merchkit (read case study)
Unified.to is fast—because we're built differently. Our declarative integration architecture lets our team ship new integrations and enhancements quickly, without brittle per-customer implementations or long onboarding delays. That kind of velocity comes from a platform that's designed to scale with your team, not block it.
TL;DR – Merge vs Unified.to
Merge | Unified.to | |
---|---|---|
Data model | Shallow normalization across 6 categories | Deep, consistent normalization across 19+ categories |
Real-time support | Polling + limited webhooks | Native + Virtual Webhooks |
AI readiness | Non-real-time, partially unified data that impedes efficient AI model training | Clean, normalized, and real-time data designed for training and fine-tuning AI models |
Data storage | Caches and stores your customers' third-party data | No caching or storing of your customers'third-party data |
Flexible delivery | API only | API, Webhooks, Database Sync |
Lock-in risk | High | Low |
Best for | SaaS-only use cases, limited to HR/ATS sync | AI-native and SaaS use cases, real-time features, and multi-category integrations (HR, ATS, Calendaring, Messaging, Accounting, and more) |
View in-depth integration technology comparison
Final thoughts
If you're building a modern product —something real-time, AI-powered, or deeply integrated across multiple SaaS systems—you'll need more than Merge.
Unified.to is the best unified API for AI-native, real-time applications.
It gives your team:
- Control over your data
- Real-time delivery at scale
- A unified layer that powers your entire product — not just one integration vertical
Start your free 30-day trial or talk to our team to see how fast you can go from idea → integration → AI-powered feature.