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Apache Ossie (incubating) is the
universal standard for semantic data
Apache Ossie (incubating) is an industry-wide specification effort to standardize how we exchange semantic metadata across analytics, AI and BI platforms, providing a vendor neutral, single source of truth for semantic data. Ossie was previously known as Open Semantic Interchange (OSI).
Write Once, Query Anywhere.
Stop redefining "Revenue" in every dashboard. Apache Ossie uses a declarative YAML standard to define metrics, dimensions, and joins — so every tool and agent in your stack works from the same source of truth.
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Consistent Definitions
Ensure Marketing, Finance, and Sales all see the same numbers — no more metric drift.
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AI-Ready Context
Give LLMs the semantic context they need to answer business questions accurately.
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No Lock-In
Move your business logic between platforms freely. Your metrics belong to you.
sales_analytics.ossie.yaml
semantic_model: - name: ecommerce_analytics description: Sales and customer analytics ai_context: instructions: "Use for sales analysis" datasets: - name: orders source: sales.public.orders primary_key: [order_id] fields: - name: order_date dimension: is_time: true metrics: - name: total_revenue expression: dialects: - dialect: ANSI_SQL expression: SUM(orders.amount)
About Apache Ossie
Apache Ossie is a collaborative, open-source effort dedicated to standardizing and streamlining semantic model definitions across the data analytics, AI, and BI ecosystem.
Interoperability
Seamlessly exchange semantic models between AI agents, BI platforms, and analytics tools.
Consistency
Maintain consistent data definitions and values across every platform in your ecosystem.
Vendor-Agnostic
A common standard that works across all vendors, eliminating tool-specific inconsistencies and lock-in.
Efficiency
Reduce engineering debt and accelerate innovation by using a unified, governed semantic foundation.
The Challenge Semantic Fragmentation
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Metric Drift Inconsistent KPIs across different dashboards.
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Manual Translation Costly, error-prone reconciliation efforts.
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Hallucinations Unreliable AI grounding from conflicting data logic.
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Integration Debt Complex N-to-N custom integrations between proprietary tools.
The Solution A Unified Standard
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Single Source of Truth Unified semantic and metric definitions.
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Native Interoperability Direct exchange between platforms and AI agents.
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Trusted AI Grounding Agents reasoning accurately based on business logic.
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Reduced TCO Lower costs through automated model exchange.
Core Classes
The Apache Ossie specification defines these building blocks:
Semantic Model
Top-level container representing a complete model with datasets, relationships, and metrics.
Datasets
Logical business entities — fact and dimension tables with fields and structure.
Fields
Row-level attributes for grouping, filtering, and metric expressions.
Metrics
Aggregate calculations — sums, averages, ratios — spanning multiple datasets.
Dimensions
Categorical attributes: Where, When, Who.
Relationships
Foreign key constraints connecting datasets, supporting simple and composite keys.
Working Group Contributors Affiliation
Leading organizations collaborating as part of Ossie to build the future of open semantic interoperability
Alation
Ataccama
Anomalo
Atlan
AtScale
Bigeye
BlackRock
Blue Yonder
CARTO
Cloudera
Coalesce
Collate
Collibra
Coginiti
Count
Credible
Cube
Dataiku
Databricks
DataHub
Denodo
dbt Labs
Dremio
Domo
Elementum AI
Entropy Data
Firebolt
GoodData
Hex
Honeydew
Informatica
Instacart
JetBrains
Lightdash
Metabase
Mistral AI
Omni
Oracle
Preset
Qlik
RelationalAI
Salesforce
Select Star
ServiceNow
Sigma
Snowflake
Starburst Data
Strategy
Sundial
ThoughtSpot
Zeta Global
Working Groups
The initiative is organized into focused groups, each tackling a specific area of the specification.
Advanced Metrics & Expression Language
Complex metric calculations and a portable expression syntax
Composability
Enabling semantic models to reference and extend one another
Catalog Integration
Bridging Apache Ossie models with data catalog and governance platforms
Ontology Representation
Mapping Apache Ossie concepts to formal ontology standards
Model Converters & Developer Tools
Tooling for importing, exporting, and validating Apache Ossie models
Latest Updates
News and announcements from the Apache Ossie community
July 10, 2026
Apache Ossie (Incubating): The New Name for Open Semantic Interchange
The Open Semantic Interchange project has been accepted into the Apache Incubator under a new name — Apache Ossie (incubating). The spec, the community, and the mission haven't changed, but the name, governance home, and long-term trajectory have.
June 4, 2026
The FSI Semantic Working Group Is Live
The Financial Services Semantic Working Group has held its first formal meeting, bringing together practitioners from across banking, insurance, asset management, and market infrastructure to solve the industry's semantic alignment challenge.
April 28, 2026
OSI Community Update: What's New and What's Next
The OSI specification is live, working groups are taking shape, and 14 new participants have joined the initiative.
March 24, 2026
Denodo Joins Snowflake to Advance Open Semantic Interchange
Denodo joins Snowflake and industry leaders to advance data and AI interoperability through the Open Semantic Interchange.
February 10, 2026
Databao Becomes a Partner of the Open Semantic Interchange Initiative
JetBrains' Databao becomes a partner of the OSI initiative, contributing its open-source context engine and data agent to the ecosystem.