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GT.M vs InterSystems IRIS

GT.M: FIS's high-throughput M (MUMPS) database and compiler, behind major core-banking systems. InterSystems IRIS: Multi-model data platform (SQL, objects, globals, vectors) with built-in interoperability, big in healthcare.

key differences

  • GT.M is primarily a hierarchical database; InterSystems IRIS is relational.
  • Licensing: GT.M is open source (copyleft) (GNU AGPL v3.0 (Linux x86_64); commercial on other platforms); InterSystems IRIS is proprietary (Proprietary commercial license).
  • InterSystems IRIS is built for larger datasets (≤ 1 PB) than GT.M (≤ 10 TB).
  • Horizontal scaling is manual in GT.M and native in InterSystems IRIS.
  • Only InterSystems IRIS has joins, secondary indexes, full-text search, vector search, json.

choose gt-m for

  • +FIS Profile and other M-based core-banking systems
  • +VistA and M-based health record systems

best at · OLTP

choose intersystems-iris for

  • +Electronic health records and hospital information systems
  • +Health information exchanges and FHIR servers
  • +High-throughput financial transaction processing
  • +Supply-chain and logistics platforms needing integration plus analytics

best at · OLTP, HTAP, Real-time analytics

GT.MFIS's high-throughput M (MUMPS) database and compiler, behind major core-banking systems.
InterSystems IRISMulti-model data platform (SQL, objects, globals, vectors) with built-in interoperability, big in healthcare.
overview
Primary model
Hierarchical
Relational
Also supports
Key-Value
Object, Document, Key-Value, Multivalue (Pick), Vector
Type
Database engine
Database engine
Status
Active
Active
Developer
FIS (Fidelity National Information Services)
InterSystems Corporation
First release
1986
2018
Latest version
V7.2-001 (Aug 2026)
2026.2 (CD) (Jul 22, 2026)
License
Open source (copyleft)GNU AGPL v3.0 (Linux x86_64); commercial on other platforms
ProprietaryProprietary commercial license
Free tier
✓
✓
popularity
WhichDB Score
8.1
13.3
Rank
#331
#253
GitHub stars
–
–
Stack Overflow questions
90
42
scale & guarantees
Comfortable data size
Medium (≤ 10 TB)
Large (≤ 1 PB)
Horizontal scaling
Manual
Native
Multi-region
Read replicas
Read replicas
ACID
Full
Full
Consistency
Strong
Strong
Schema
Schemaless
Flexible
Architecture
Single node, Primary replica
Client server, Primary replica, Distributed
deployment
Self-hosted
✓
✓
Vendor-managed cloud
—
✓
Serverless
—
—
Embedded
—
—
Edge
—
—
Clouds
–
AWS, Azure, Google Cloud
capabilities
Transactions
✓
✓
Joins
—
✓
Secondary indexes
—
✓
Full-text search
—
✓
Vector search
—
✓
Geospatial
—
—
JSON
—
✓
Change data capture
—
—
Triggers
✓
✓
Stored procedures
—
✓
Materialized views
—
—
TTL / expiry
—
—
Pub/Sub
—
—
Columnar storage
—
✓
In-memory
—
—
Durable persistence
✓
✓
Compression
—
—
Encryption at rest
✓
✓
Role-based access
—
✓
Time travel
—
—
Branching
—
—
Online schema changes
—
—
Streaming ingest
—
—
Offline sync
—
—
Runs in WebAssembly
—
—
interfaces
Query languages
M (MUMPS)
SQL, ObjectScript, Python (Embedded)
Client languages
M, C
Java, C#, Python, JavaScript, C++
Best for
OLTP
OLTP, HTAP, Real-time analytics, Vector search
Add more to this comparisonNot sure either fits? Try smart match

GT.M vs InterSystems IRIS: FAQ

What is the difference between GT.M and InterSystems IRIS?

GT.M: FIS's high-throughput M (MUMPS) database and compiler, behind major core-banking systems. InterSystems IRIS: Multi-model data platform (SQL, objects, globals, vectors) with built-in interoperability, big in healthcare. GT.M is primarily a hierarchical database; InterSystems IRIS is relational. Licensing: GT.M is open source (copyleft) (GNU AGPL v3.0 (Linux x86_64); commercial on other platforms); InterSystems IRIS is proprietary (Proprietary commercial license). InterSystems IRIS is built for larger datasets (≤ 1 PB) than GT.M (≤ 10 TB).

When should I choose GT.M over InterSystems IRIS?

Choose GT.M for FIS Profile and other M-based core-banking systems; and VistA and M-based health record systems. Choose InterSystems IRIS for electronic health records and hospital information systems; health information exchanges and FHIR servers; and high-throughput financial transaction processing.

Is GT.M or InterSystems IRIS more popular?

InterSystems IRIS ranks #253 on the WhichDB Score (13.3/100) and GT.M ranks #331 (8.1/100). Popularity is not fit: check the requirements that matter for your project.

Are GT.M and InterSystems IRIS open source?

Yes. GT.M is open source. License: GNU AGPL v3.0 (Linux x86_64); commercial on other platforms. No. InterSystems IRIS is proprietary, closed-source software.