ohi LinkML

Model your data or domain once, in a simple YAML schema. ohi LinkML checks it and turns it into the code, ontologies, and schemas your tools already use.

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Free and open source · Apache 2.0

One model, many formats

LinkML is an open language for data and domain modeling.

You write your data model or ontology once. ohi LinkML then generates the artifacts needed for your stack: your API, database, knowledge graph and business logic all use the same source of truth.

You can also convert your existing models in Apache Ossie, OWL, or RDFS to LinkML to get started.

schema.yaml

classes:
  Book:
    attributes:
      title:
        required: true
      author:
        range: Person

Schemas: JSON SchemaGraphQLFrictionlessSHACL
Ontologies: OWLRDFSApache Ossie
Code: PydanticTypeScriptScala
Docs: MarkdownER diagrams

Precise validation

ohi LinkML tells you exactly what is wrong in your schema, or writes a JSON report for your tools.

Runs anywhere

Browsers, Node.js, the JVM, Python, and native binaries for Linux, macOS and Windows.

Quick, even on huge schemas

Natively-compiled CLI starts in milliseconds and stays fast even with huge schemas.

Install

Terminal

$ . <(curl -sSfL https://raw.githubusercontent.com/NeverBlink-OSS/linkml-scala/refs/heads/main/cli/install.sh)
$ linkml-scala validate schema.yaml

Linux, macOS, and WSL. Read the script before you run it: cli/install.sh. Or download a binary from the latest release.

Terminal

$ mise use ubi:NeverBlink-OSS/linkml-scala

Any platform, Windows included. See mise.

Terminal

$ npm install @neverblink/linkml

One ES module with TypeScript types and no dependencies. On npm.

Terminal

$ pip install neverblink-linkml

Python bindings, plus a C ABI for C, C++ and Rust. On PyPI.

build.sbt

libraryDependencies += "eu.neverblink.linkml" %% "generator" % "0.17.2"

On Maven Central, for the JVM, Scala.js and Scala Native. See the Javadoc.

.github/workflows/*.yml

- uses: NeverBlink-OSS/linkml-scala-action@v0.17.2

Validate schemas and generate files in CI. See linkml-scala-action.

Claude Code

> /plugin marketplace add NeverBlink-OSS/linkml-scala
> /plugin install linkml@linkml-scala

Codex

$ codex plugin marketplace add NeverBlink-OSS/linkml-scala

Then open /plugins in Codex and install linkml. The skills run the CLI, so install that too. For other agents that support Agent Skills, see installing the skills by hand.